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My name is Joshua Sheets. I'm your host. On a recent podcast, I talked to you about how to maximize your height so that you have the best possibility of gaining all the benefits that come from being tall. The specific connection to personal finance is that we have some academic estimates and scholarly discussions that estimate that for about every inch of height that you have over the normal person, you can increase your earning power by perhaps more than 2%.

The numbers vary a little bit, but 2% is a conservative estimate. I've seen as high as 2.8%, so I just call it 2% to be safe. Now, most of that discussion, though, is centered on men because the differences for income related to height are primarily or most marked with regard to men.

They're not so clear in the data with regard to women, and that would make sense to us, I think, generally. It would make sense that men and women are treated differently, and there's a different set of traits and characteristics that women are judged by versus the ones that men are judged by.

But just because I focused on that in that podcast episode doesn't mean that any of the advice that I gave was necessarily inapplicable to women. After all, our daughters, especially during their puberty years and teenage years, our daughters need to have ample amounts of food. Our daughters need to have ample amounts of sleep.

Our daughters need to have ample amounts of physical exercise. But the question is, is there something that is different about trying to transmit these characteristics to men versus to women? And I think there obviously are. After all, if I play fast and loose with the things that we don't have data for, for example, we understand that people who are good looking probably get kind of a beauty premium.

A man who's very handsome or a woman who's very beautiful has an easier time in some things in the world. Somebody who's in great shape. We could go on and on with this logic forever. But what I want to do in today's podcast is I want to share with you some information that I learned from a book called Girls on the Edge by Dr.

Leonard Sachs, specifically about the things that we should be treating differently in the physical development of women and our daughters as compared to the physical development of men. Because a lot of things related to the body, the development of the body, the development of athletic ability, a lot of our focus historically comes from men, from helping to develop young men.

And a lot of the things that we do to develop young men can be very damaging to women. Now, this, the outline of what I'm going to share with you comes from chapter six of Girls on the Edge. Chapter six is entitled Body. And it's not the most important thing.

His first chapter was he talked about the sexual identity of girls. Chapter two, he talked about social media. Chapter three, dreams and obsessions. Chapter four, environmental toxins. Chapter five, mind. This chapter, body. And then the next chapter, spirit. It's a good book that I recommend, and I've shared with you some resources from this book previously.

But specifically with regard to helping our daughters to develop their bodies, we need to understand that the way that we treat girls in their physical development needs to be different than the way that we treat boys. That doesn't make it any less important. We want our daughters to be strong and confident.

And a huge component of that personal strength and confidence comes from their physical development. But we need to understand that it's a little bit different. So I'm just going to jump into this. Consider this to be a personal finance light episode. If you're interested in these topics related to human development, you'll enjoy this episode.

If you're looking for nuts and bolts on personal finance, this isn't your cup of tea. I will, one final note before I get into the text is simply that this chapter is, as is this entire book, heavily footnoted, I counted 76 footnotes for all the statements that Dr. Sachs makes in this particular chapter.

I'm not going to try to cite everything because that's annoying. But just know that if you're interested, check out this book, Girls on the Edge. If you intended for a girl to suffer a major injury, you would take away all her other sports before puberty, make her play her one sport all year round, and then you would just wait.

Michael Sokolov. Which is better, hopscotch or baseball? Jump rope or soccer? Better for whom? Better for what? Physical education for elementary school kids in North America usually includes instruction in baseball, learning how to swing a bat to hit the ball, run the bases, and so forth. It's much less common for kids to receive formal instruction in hopscotch.

We encourage kids to play competitive soccer far more often than we encourage them to play competitive jump rope. How come? 8-year-old boys are, on average, better than girls at tasks that require targeting a moving object in space, which means boys are likely to have an edge in games that involve swinging a bat to hit a pitched ball or kicking a moving soccer ball into a goal.

8-year-old girls are, on average, better than boys at tasks that require balance, which means girls will have the edge in games such as hopscotch or jump rope. Our physical education programs for children usually promote sports where boys have the advantage while de-emphasizing or ignoring sports where girls have the advantage.

When surveyed, girls typically think boys are better athletes than girls. One reason may be that our physical education programs emphasize sports such as baseball, football, and soccer in which boys enjoy advantages while devaluing or ignoring activities where girls enjoy the advantage, such as the balance beam, hopscotch, or jump rope.

Ignoring gender puts girls at a disadvantage. In the gym, as in the classroom, we teach girls pretty much the same way we teach boys simply because there hasn't been much serious consideration that maybe what works best for boys might not always work best for girls. I still encounter suspicion when I suggest that girls should be taught differently, either in the classroom or on the playing field.

Whenever I make such a suggestion, I often get the response, "Are you suggesting that girls can't do what the boys can do?" But ignoring differences between girls and boys doesn't provide a level playing field. As we will see, it often puts girls at a disadvantage and at risk. A second reason that so many girls believe that boys are better athletes is probably because the boys tell them so, beginning in elementary school.

Many boys boast about their athletic prowess. As one team of investigators reported, girls are more realistic about their competencies while boys overestimate their physical competence, especially in the early years. Most adult women, and many teenage girls, have figured out that boys often exaggerate their athletic skills, but most eight-year-old girls haven't yet discovered that boys are not trustworthy regarding their self-assessment of their own athletic ability.

Now, I'm going to make comments as I read this, and I think one of the reasons I want to share this information with you is that I believe it's our responsibility to cultivate environments in which boys can thrive and in which girls can thrive. We can't, maybe it's out there, maybe I just haven't found the research yet.

We can't, so I'll make my statement, but I don't know of how we can estimate specifically the impact of personal self-confidence on income, on the amount of income that is earned. If those studies have been done, I haven't stumbled into them yet, but I haven't gone looking. There was a lot years ago in the self-esteem world and self-confidence and all of that.

My basic way of summarizing what I understand about that area of research is that self-confidence is real, self-esteem is real, but it has to be earned. It has to be earned by genuine accomplishment. Kind of fake confidence or just pretending that you have it is of only limited value.

It has to actually be earned. So if we want our children and ourselves to succeed, we need to create environments in which we can genuinely succeed, and what's interesting is it doesn't have to be any one particular thing. So what we need to do is we need to create environments in which our boys and our girls can work hard and develop skills that allow them to truly shine.

The problem is that in today's androgynous world where we're all bent and determined to never ever indicate that there may be any difference between boys and girls, because to indicate so would be a complete failure of all of our modern gender experiment, we wind up handicapping boys and girls.

And I've found that basically in every area this is difficult. We'll talk more in this chapter about the value of boys-only education or boys-only classes and girls-only education, girls-only classes, and you'll see some of the research that we know on this. But bring it up. We brought it up.

My wife has brought it up in kind of our homeschool co-op, which is a conservative homeschool co-op filled with Christians, it's a Christian homeschool co-op, and yet nobody is willing to even consider the idea that boys and girls learn differently. Nobody is willing to even consider the fact that, hey, let's try out some things that are gender-divided because somehow that would be bad for the girls.

What's the point of physical education? Why bother? Is it about the joy of sports? But the sports that bring joy to a child may be different for girls compared with boys. And the best way to engage girls in sport is often different from the best way to engage boys.

Men may be less likely to understand how to engage girls in sport than women are. If that's true, it would be helpful to have women coaching girls. But the majority of coaches for most team sports are men. In fact, the proportion of coaches who are women has actually declined significantly over the years.

In 1972, 90% of coaches of women's teams at American colleges and universities were women. In 2006, the proportion of women coaches among coaches of women's sports had dropped to 42%. The latest survey shows that proportion to have dropped further, slightly, to 41%. So, we went from 90% to 41 or 42%, cutting more than half.

We have more girls and young women playing sports today, but proportionately fewer women coaching them. That's true at every level, from beginner leagues for seven-year-olds right up through college. As Michael Sokolov writes in his book about girls in sport, "The unspoken feeling in many settings is that men know sports.

They've been at it longer. So, if you want your daughter's travel team to succeed and the girls to get scholarships, you'd better have a male coach." Among parents who have kids playing competitive sports, more than 27% of fathers coach their child's sport team. Less than 4% of the mothers are coaches.

That imbalance leads to a third reason why so many girls assume that sports are, fundamentally, male territory. The experts, the coaches, are overwhelmingly male. The fact that so many girls think that males are better at sports may also explain why most girls attach more weight to their father's opinion about their own athletic ability than they do to their mother's opinion.

Gym teachers matter. Coaches matter. The style of the coach or the P.E. teacher may have a big influence on how your daughter views sports and her own ability to play. Some coaches have a relentless focus on playing to win. That's not helpful for most kids, both girls and boys, but it's particularly harmful for many girls.

The research consistently shows that girls are more likely to be engaged in sports when coaches focus on helping kids master skills, praising good performance, and offering encouragement and supportive criticism when girls make mistakes. Coaches or gym teachers who make fun of the klutzy kids or coaches who ignore kids who aren't athletically talented will not make good coaches for most girls.

We also know that coaches who play favorites can turn girls off a sport very quickly. If girls believe that the coach has favorites, then the unfavored girls may quit. Girls should be active and as athletic as they can be, within healthy limits. We discuss some of the limits in Warning Science in Chapter 3.

As a parent, you can help your daughter choose the sports and physical activities she most enjoys, and where she can fulfill her athletic potential with the greatest benefits and lowest risks. All sports carry some degree of risk, of course. You must understand the risks and balance them against the benefit.

In helping your daughter choose a sport, the first question you need to answer is this, which are the most dangerous sports? I think you're going to enjoy this section, it's pretty astonishing. Ashley Marie Burns was just a few weeks away from starting 9th grade. She was one of 12 incoming freshman girls chosen for the cheerleading team at Medford High School in Massachusetts.

She and three other girls were rehearsing a stunt called an arabesque double down. The three other girls were to throw Ashley in the air and then catch her. Ashley had previously executed the stunt without a problem. Indeed, she was renowned as one of the best flyers on the squad.

At 4.51 p.m., the girls tried the stunt. Ashley came down wrong, landing in the other girls' arms with her chest down instead of on her back. She didn't appear to be injured, nothing was broken or dislocated, but she complained of feeling short of breath. The coach told her to stretch her hands over her head and then send her to the bathroom to splash cold water on her face.

Ashley still didn't feel right, but nobody called 911 until she passed out half an hour later. She never regained consciousness. She was pronounced dead at the hospital at 6 o'clock p.m. An autopsy revealed that she had lacerated her spleen when she fell. She died of massive internal bleeding. Unfortunately, Ashley's story is not unique, nor was her injury an incredibly rare accident.

Girls' cheerleading is by some measures the most dangerous sport kids do today. More dangerous even than football or ice hockey if the measure of danger is the number of serious injuries per thousand athletes. The National Center for Catastrophic Sports Injury Research (NCCSI) publishes an annual report chronicling deaths and serious injuries sustained by high school and college athletes.

Over 25 years, the NCCSI documented a total of 156 serious injuries or deaths among high school girls and college women. Of those, 97 occurred in cheerleading. That's more than in all other girls' sports combined. Dr. Robert Cantu, a professor of neurosurgery at Boston University School of Medicine and a co-author of the NCCSI report says, "What's staggering, really, is that the single most dangerous activity in sports in schools is to be a flyer in cheerleading," he says.

The chance for catastrophic injury is exponentially higher than for any other sports activity. Cheerleading epitomizes some of the worst aspects of sports for girls. To begin with, there is a major emphasis on how you look. If you are playing volleyball, the coach isn't going to care (and shouldn't care) whether your socks match or whether your gym shorts have a smudge of dirt on them.

But in cheerleading and related sports like drill team and dance team, you not only have to execute the stunt, you also have to look pretty and smile while you do it. In most jurisdictions, cheerleading is organized as an "activity" rather than a bona fide sport. That means that the safety requirements for the cheerleading squad are no different from the requirements for the chess team or the debate team.

The chess team isn't required to have a certified athletic trainer in attendance. Neither are the cheerleaders. The coach of the debate team isn't required to be certified in injury assessment. Neither is the coach of the cheer squad. Ashley's life might have been saved if the adults in attendance had understood the risks of splenic injury after a fall and had called 911 immediately rather than waiting until Ashley lost consciousness.

Cheerleading has changed dramatically over the past four decades. Thirty years ago, cheerleaders were usually girls who jumped up and down on the sidelines leading cheers. Nowadays, the emphasis, beginning around age 10, is on high-flying stunts. Today, cheerleading most closely resembles the sport of gymnastics, only without the mat and safety regulations, says former Massachusetts State Representative Peter Kutugian, who is trying to make cheerleading safer.

Kimberly Archer, founder of the National Cheer Safety Foundation, says that the emphasis is on "death-defying, gravity-defying stunts. That's a long way from shaking pom-poms on the sidelines like I did in the '80s." If your daughter is five or six years old, you may think this advice doesn't apply. Nobody is going to ask your daughter to do an airborne somersault anytime soon.

But there are long-term consequences to the choices that young girls make about which activities and sports they will participate in. Ask any girl over eight years of age which sports she likes the most, and the answer will almost invariably be whatever sports her friends do. If she joins midget poms at age six, she will probably want to carry on with her friends to junior cheer.

At age 10, when she's been with the same girls for four years and the coach is beginning to teach them some airborne stunts, it may be difficult for you to suggest that she switch to a safer sport. She will say, "But all my friends are on the cheer squad!" And she may be right.

It's much easier to steer your six-year-old daughter in a healthy direction than it is to ask your 10-year-old daughter to change her sport and her friends. Encourage your daughter to choose sports in which the emphasis is on what she does on the field of play, not on how she looks while she's doing it.

Archery, badminton, field hockey, soccer, softball, swimming, tennis, track, and volleyball are all good choices by that criterion. Cheerleading, dance team, and gymnastics may not be good choices. The risks in cheerleading, dance team, and gymnastics often outweigh the benefits of exercise. The focus on appearance, on looking cute, is often relentless.

Don't allow your daughter to specialize too early. Specializing in a sport before the onset of puberty appears to increase the risk of physical injury and mental burnout. According to an official policy paper from the American Academy of Pediatrics (AAP), those who participate in a variety of sports and specialize only after reaching the age of puberty tend to be more consistent performers, have fewer injuries, and adhere to sports longer than those who specialize early.

A second AAP committee examining the same question came to the same conclusion. Young athletes who participate in a variety of sports have fewer injuries and play sports longer than those who specialize before puberty. The National Athletic Trainers Association recently issued similar guidelines. Kids should take at least two days a week off from their sport, should not specialize in one sport year-round, and should postpone specializing in one sport as long as possible.

In his book about girls who get hurt playing sports, Michael Sokolov writes that "nearly every injured athlete I met in the course of researching this book played one sport exclusively beginning at age 10 or younger." By the way, to make clear, this section here on specialization is not specific to girls.

It is applicable to girls, but it is not specific to girls. This is the same advice that other parents need to be paying attention to with regard to boys. And in our current kind of pedestalization of professional sports, there are many parents who are very much focusing on their children, their young children, specializing in a certain sport and taking advanced training in that sport with the hopes of reaching some very high level of performance in that sport.

I've spent a good amount of time digging into this just out of my interest in trying to shore up my knowledge of athletics and knowledge of sport and how to prepare children for that and things like that. And universally this is condemned, universally by all trainers, coaches, everyone who's involved in that space who has the perspective of time.

It is a key thing that is promoted basically by parents who are intent on, in the best of cases, helping their children to specialize in a particular sport that they really want to help them go to college. In the worst of cases, to live out some unfulfilled dream from the parent's own childhood, from the father's own childhood of what could have been if I had worked harder.

But children should not be specializing in a certain sport. And so just broadly speaking, if you want your children to be strong and athletic, as I do, as we should, because, again, tying it with personal finance angle, it helps children to be strong. The competition is really important. There's all kinds of lessons that can be learned.

All of these things are good things. But the best approach is do not specialize in a sport. Play multiple sports for multiple seasons so that there's variety. And there's huge cross-training benefits even for the long-term specialization. There's huge cross-training benefits that come from playing a multitude of sports. I like the idea.

I heard recently, I was with a lady that my wife and I were having dinner with her. And she said her family's rule was always this, you have to always be playing a sport. You get to choose what it is, but you have to be playing a sport. That's an appropriate thing.

And so if you look at the traditional schedule, at least in North America, where I'm familiar with it, where you have your fall sports, your winter sports, and your spring sports, this is an appropriate thing to have a short season, working on these sports skills during that time, and then having abundant amounts of time off.

Back to the book. Don't allow your daughter to compete in the same sport year round. In the 1980s, it wasn't possible to play the same sport year round. There was soccer or field hockey in the fall, basketball in winter, and lacrosse or track or tennis in the spring. But beginning in the early 1990s, club teams and travel teams began to grow in popularity.

Now it's common to find girls playing on a club team all year long. But the evidence strongly suggests that specializing in one sport and competing in that sport year round greatly increases the risk of injury. Each sport uses a particular group of muscles. Overdeveloping one set of muscles while neglecting the others throws the body out of alignment.

There's a second reason, aside from the risk of injury, why your daughter should not compete in the same sport year round. If she's playing the same sport winter, spring, summer, and fall, she's likely going to be with the same group of girls for a great deal of time. Being respected and liked by those particular girls may become the highest priority in her life.

If she sustains a minor injury, she will be less likely to mention her injury to anyone for fear that the doctor might restrict her participation. Her enthusiasm for the sport itself may wane, but she won't consider quitting the team, because that's where her friends are. The time commitment may be causing her grades to suffer, but she doesn't want to let her friends down.

It's all about balance. Sports are great. But when a particular sport becomes an obsession, it's time for you to step in. You and your daughter have to find a sensible balance between risk and benefits. As Sokolov observes, "We can't prevent every injury, but what we are currently doing is manufacturing them." If you intended for a girl to suffer a major injury, you would take away all her other sports before puberty, make her play her one sport all year round, and then you would just wait.

The earlier you make your intervention, the easier it will be. Too many parents today go with the flow until it's too late. We all want to be supportive of our daughter's interests. What could be healthier than sports? Sokolov describes parents of highly motivated girls, parents who are supportive of their daughters but bewildered by the culture.

"The children, as often as not, are the ones leading the way," Sokolov found. "They do not so much put pressure on themselves as they absorb it from the youth sports culture. The parents get subsumed in ways they never anticipated." We had no idea what we were getting into, says one parent.

You just feel your way as you go. Don't be that parent. Know what your daughter is getting into before it's too late. Don't be intimidated by the coach or by the culture. You know better than the coach what is best for your daughter. Your coach has a different agenda.

He is concerned about winning. If your daughter is injured, emotionally or physically, it's not his problem. It's not going to keep him awake at night. There are other girls who can take her place. In the name of safety, don't allow your daughter to focus only on sports that involve the same muscle groups.

A girl who plays soccer in the fall and runs track in the winter and spring is running all the time. Swimming would be a better winter sport for her, because swimming exercises different muscle groups, complementary to those used in running. Many parents, especially in the United States, assume that early specialization in a particular sport will give their daughter a competitive advantage.

The evidence doesn't support that notion. Colleen Hacker, who has served as a psychologist for U.S. women's soccer for more than 20 years, told Sokolove, "The big misconception is thinking that there is a linear connection between the development of a young athlete and the time spent being coached, attending organized practices, and playing organized games.

There's no support for that. There may be a belief and a hope, but not evidence." The most successful athletes, the ones who make it to the Olympics, usually have a history of playing many sports, specializing only once they reach their teens. Diversity of experience, cross-training, makes the body stronger, better coordinated, and less prone to injury.

Dr. Hacker expresses frustration that so many parents don't understand this basic reality about the developing human body. This message, about the importance of athletic diversity, is not getting across, she says. We need to encourage parents, coaches, sports leagues, and the culture itself to go back to multiple sports participation, and there needs to be real off-seasons with unstructured play.

No adults, no rules, no leagues, no registration cards. One of the best sentences a parent can utter is, "Go outside and play." One of the worst is, "It's 9 a.m., get in the car, we're going to practice." Not all girls care about team sports. Some girls do care passionately about team competition, about victory and defeat.

For those girls, the traditional sports of soccer, basketball, and baseball or softball may be a good match. But many girls are not particularly motivated by the opportunity to bash the other team. If you have the sense that your daughter might be such a girl, try to expose her to a wide range of activities, including those that don't necessarily involve team competition – martial arts, fencing, and archery, to name three.

Some of these sports can be done in a team-competitive way, but they don't have to be, and often are not. A girl's knee is not a boy's knee. The most popular team sports, such as soccer, baseball, and basketball, were developed mainly by men to be played by men and boys.

In the past 50 years, girls have begun playing these sports in record numbers. For the most part, they are playing boys' sports according to boys' rules, and they are usually coached by men. Few people have asked whether these sports should be modified to make them safe for girls. Many people bristle when this question is raised.

"Are you suggesting that girls are not as tough as boys?" one parent asked me. On the contrary, girls seem to be tougher. If the criterion of toughness is how severe an injury is needed to knock the athlete out of the game, girls and young women appear to be more willing to play while injured compared to same-age boys.

But girls are different. When researchers tested girls and boys at 8 years of age, they found that girls' quadriceps were very strong relative to their hamstrings, while boys had more of a balance between their hamstrings and quadriceps. In case you're a bit weak on anatomy, the quadriceps is the foreheaded muscle on top of your thigh bone that straightens your leg.

The hamstrings are the muscles in the back of your thigh that bend your leg. Puberty exacerbates these differences. As a girl's hips widen, her Q angle increases. The Q angle is the angle formed by the femur (the thigh bone) in relation to the vertical. The widening of the pelvis that is a normal part of puberty in girls leads to a larger Q angle for young women.

As a result, activities that involve the quadriceps (activities such as running, jumping, or kicking a ball) create a more severe torque on the anterior cruciate ligament (ACL) in girls than in boys. Fatigue stresses the female knee differently and more severely compared with the male knee. A girl's leg responds differently to a run-and-cut maneuver compared with a boy's executing the same maneuver.

As a result, girl gymnasts are more than five times as likely to injure their knees compared to boy gymnasts. Girls playing basketball are more than twice as likely to rupture their ACL than boys playing basketball. College women are four to six times more likely to injure their ACLs than men playing the same sport at the same level of competition.

The consequences of knee injuries can be significant and long-lasting. If your daughter experiences an ACL injury, there is more than a 50/50 chance that she will develop significant arthritis in that knee within 7 to 20 years after the injury. She may need a knee replacement by the time she's in her 30s.

Girls who are injured are more likely to be re-injured compared with boys who suffer the same injury playing the same sport. This is not because girls are more fragile than boys, but because the entire culture of sport has developed around what works for boys, not what works for girls.

For example, consider how coaches usually warm up their players before a game. Generations of men have prepared boys before a game by having the boys run a few laps around the track or do some jumping jacks or simple stretching exercises. That may be fine for boys, but it's not helpful for girls.

Orthopedic specialists designed a completely different warm-up routine based on girl-boy differences in anatomy. The girls' warm-up routine should involve, among other things, running backward, as well as prone hamstring flexion exercises. It doesn't cost any more money or time than the boys' routine. It doesn't require any special equipment. But it's different.

When girls do these "girl-specific" routines before practice and competition, the risk of ACL injury is reduced by an astonishing 88% compared with girls on comparable teams doing the traditional warm-up. Ask the coaches of your daughter's team whether they are aware of this "girl-specific" warm-up and its proven benefits. If they aren't, make sure they learn.

A girl's head is not a boy's head. Samantha Furstenberg was a top-ranked high school lacrosse player. She was sprinting with the ball toward the opposing goal in a high school game. Three girls defending the goal tried to stop her. At least one girl whacked her in the head with a lacrosse stick.

Samantha never lost consciousness, but she didn't feel right. She sat out of the game for a few minutes, then she went back in. Samantha had suffered a concussion. For several days, she was nauseated, felt dizzy, and had difficulty thinking clearly. Her parents took her to see a specialist at Children's Hospital in Washington, D.C.

When her symptoms persisted, Samantha and her parents traveled to consult another specialist at the University of Pittsburgh. Even three weeks later, her symptoms were nearly as bad as they had been the day after the game. She couldn't focus for more than 10 or 15 minutes at a time. It took months for her to recover fully.

More than a year later, Samantha sustained a second concussion during a lacrosse match. But she wouldn't give up the sport. She was recruited by Colgate to play NCAA Division I lacrosse. However, just a few days before she was to leave for Colgate, she bumped her head while tubing on a lake.

The headaches and dizziness returned. After consulting with specialists, Samantha decided to leave the team and end her career as a competitive lacrosse player. The risks were too great. "Over the next few months, I struggled to define myself without lacrosse shaping who I was and what I did," she told me.

She decided to transfer from Colgate to Georgetown, and she took up long-distance running. One year later, she ran the Marine Corps Marathon for the Make-A-Wish Foundation. "But I definitely miss playing lacrosse," she told me at the time. Most team sports are played by the same rules for girls and for boys at the high school and college level.

Lacrosse is a notable exception. Boys are required to wear helmets while playing lacrosse. Girls aren't. The reason given is that boys' lacrosse is a contact sport. Boys are allowed to make physical contact with other boys. Girls' lacrosse is supposedly a non-contact sport because girls are not supposed to make intentional physical contact with other girls.

For most of the past century, research on sports-related head injuries meant research on sports-related head injuries for boys and men. Even though girls and women have been playing competitive sports for decades, the first attempt at a thorough investigation of the risk for girls compared to boys wasn't published until 2007.

That study, undertaken by the NCAA in association with Ohio State University and based on data from 100 high schools and 180 universities across the United States, demonstrated that girls playing high school soccer have a risk of concussion 60% higher than boys. Girls playing high school basketball have a risk of concussion 300% higher than boys.

Which NCAA has the highest concussion rate measured as a number of concussions per time rate? If you said football, you'd be wrong. The college sport that carries the highest risk of concussion is women's ice hockey. Women playing ice hockey have more than double the risk of concussion than men playing college football.

In every sport played by both girls and boys—basketball, soccer, ice hockey, lacrosse—girls' risk of concussion is significantly higher than the risk for boys. One can imagine several possible explanations. However, the most plausible explanation is that girls' heads are built differently from boys' heads. Consider the lateral ventricles, which are basically big holes in the brain that contain nothing but cerebrospinal fluid, the watery liquid that encases and insulates the brain.

These fluid-filled holes in the brain are significantly bigger in boys than in girls, even after adjusting for any differences in overall body size. The lateral ventricles act as fluid-filled hydraulic shock absorbers. If a boy's head collides with a soccer ball, the odds of damage are lower than if a girl's head collides with the same soccer ball.

That makes sense if the boy's lateral ventricles are bigger than the girls'. He has more empty space in his head to absorb the blow. Some have suggested that maybe the reason that girls have a greater risk of concussion is merely because girls are, on average, smaller than boys. That hypothesis doesn't fit the facts.

Girls are more likely to have a concussion compared with boys of the same size, and girls are more likely to suffer lasting cognitive deficits after concussion than boys are. These sex differences are not attributable to differences in overall size or body mass, according to researchers who have carefully controlled for these variables.

Dr. Joseph Blyberg is a clinical neuropsychologist with a particular interest in head injuries. He says that comparing the male and female skull and brain is "like comparing an SUV and a Volkswagen bug. The same level of impact is probably not going to cause the same level of damage." What should we, as parents, do to minimize the risk of our daughters suffering a significant head injury?

First, I think it's wise to try to steer your daughter away from the highest risk sports, such as ice hockey, figure skating, and gymnastics. Second, if your daughter is going to play an intermediate risk sport, such as soccer or lacrosse or basketball, I think you should insist that she wear the new headband-style protective gear.

These devices look like overgrown headbands, but they act like helmets. One example is the Full 90 (www.full90.com), which comes complete with an opening for your daughter's ponytail in the back. Just make sure she doesn't regard the helmet as a license to kill. Third, insist that the coach and staff have appropriate training in recognizing the signs of concussion, including sex differences in the presentation of concussion.

Male coaches, whose experience has been mostly with boys, may not be aware that girls are at higher risk for concussion. They may not be as thorough in assessing a girl for concussion after she has been knocked in the head but hasn't lost consciousness. I spoke with Samantha again in November 2019, ten years after our previous conversation.

What had happened in the years since? Samantha explained that her doctor advised her against returning to lacrosse or any sport with a high risk of head injury. The danger of another concussion and lasting disability was just too great. Instead, she plunged into endurance sports, and I use the word "plunge" literally.

In addition to running marathons, Samantha has completed three full Ironman competitions. The Ironman competition begins with a 2.4-mile swim, followed by a 112-mile bike race, followed by a 26.2-mile marathon. She now ranks in the top 5% of Ironman athletes worldwide. She has also completed several half-Ironman competitions and a number of marathons, and she has coached girls high school lacrosse.

Samantha graduated from Georgetown with a double major in math and psychology. She then went on to the Harvard Graduate School of Education, where she earned a master's degree. After three years teaching sixth-grade math, she returned to graduate school to earn a second master's degree, this one in educational innovation, simultaneously with an MBA, both at the University of Virginia.

She hopes someday to launch her own K-12 school. In her TEDxTalks, Samantha is frank about how she felt when she realized she would never play lacrosse again. She felt that she had failed. A lot of championship brands in town, and you know Galpin Ford is one of them. Number one in the world 29 years in a row.

I want you to ask for the general manager, number one guy there, Mike Schwartz, Matt MoneySmith here talking about Galpin. We've done business for three plus decades. They've done business in town for coming up on seven decades. That's what we're talking about, a championship brand. They have the inventory, over 800 vehicles ready for immediate delivery.

You don't even have to hop off the 405 at Roscoe. Find your vehicle online, they'll deliver it right to you. It's GalpinFord.com. 1-800-GO-GALPIN or hop off the 405 at Roscoe. Ask for Mike Schwartz or Paul Ulbrich. Nothing brought me joy, she said. Being in marathons and Ironman events helped her to overcome that low.

I asked Samantha what advice she would have for other girls struggling to recover after concussion. "Listen to your doctor," she said. "If they tell you to take a week off of school, do it. Try to find someone else who has gone through it. And remember, this too shall pass." A girl's bones are not a boy's bones.

When I was a medical student at the University of Pennsylvania back in the 1980s, we were taught that osteoporosis, brittle bones, is something that happens mostly to older women. By the way, let me interrupt here for a moment. Pay attention carefully to this point because the reason I do this kind of stuff, these kinds of topics, is to try to help you understand what you can do when your children are young.

As I've stated many times on the podcast, why don't I not talk about college savings accounts every day? Well, because with regard to preparing for education, it's inferior to basically every other thing that I can come up with. Same thing here with medical stuff. We want to avoid osteoporosis at a late age, but listen to how early you have to be aware of this.

Back to the book. When I was a medical student at the University of Pennsylvania back in the 1980s, we were taught that osteoporosis, brittle bones, is something that happens mostly to older women. Today, doctors recognize that although osteoporosis usually manifests in women over 60 years of age, it is best understood as a disease that begins in childhood, caused by the failure to build sufficient bone in childhood and adolescence.

A girl makes most of her bone between 6 and 17 years of age. By the time she's 17, a young woman has acquired more than 90% of all the bone mineral she will ever have. After about age 24, it's mostly downhill. I'm not saying that women in their 40s can't do anything about their bone density, but if your bones are strong at age 20, you're in good shape.

If your bone density is significantly below average at age 20, it's going to be a real struggle to make up the difference when you're in your 40s or 50s. It's much easier for women over age 30 to maintain their bone density than to try to build bone they should have built when they were younger.

So, your daughter needs to exercise right, and she needs to eat right. Researchers at Oregon State University randomly assigned children 6 to 8 years old either to jumping or stretching exercise. The jumpers were asked to jump off a 2-foot box 100 times, 3 days a week for 7 months.

The stretchers did stretching exercises for an equivalent length of time. There were no differences in bone density between the two groups of kids when they enrolled in the study, but at the end of the 7 months, the kids who had been assigned to the jumping exercise had significantly stronger bones than the kids who were assigned to the stretching exercise.

Even more important, significant improvements in bone density relative to the control group were still in evidence 7 years after the intervention ended, for girls as well as for boys. In a separate study by Canadian researchers, 10-year-old girls were randomly assigned either to high-impact exercise, lots of jumping, for 10 minutes at a time, 3 times a week, or to regular physical education for the same amount of time.

After 2 years, the girls who had been assigned to be jumpers had stronger bones than the girls who had been assigned to regular PE, even though there was no difference in bone density at the beginning of the study. Every able-bodied girl can do jumping exercises. It doesn't require any special athletic talent or any special training for staff or any expensive equipment.

So your daughter needs to exercise and so do you. You have to practice what you preach. It's great if your school's PE instructor is familiar with this research, but you can do these exercises with her yourself. Don't rely on your daughter's school or the coach of her team to make sure she gets enough exercise.

It's your responsibility to get her out of the house, jumping up and down in the field or at the park or wherever. The earlier you start, the better. By 8 years of age, girls who are more active have significantly stronger bones than girls who are less active. Let me interrupt here for a moment.

This is, if you remember in the episode where I talked about height, I emphasized high-impact activities. Now, interestingly, this is one of those things that when I said it, some people I would guess would say, "Wait a second. Why do we want high-impact activities?" As you get older, one of the things people are always looking for is, "I want low-impact activities, right?

I want an elliptical trainer instead of running because it's lower impact." But it's really, really important that young people, young children and adolescents get lots of high-impact activity, and it's specifically important for what we're talking about here, for building the bone. As I understand it, not being a medical doctor, not even being an expert on this, just trying to consume what I can learn, as I understand it, bones respond to stress.

And so one of the most important things to do to build strong bones is to stress the bones quite a lot. And stress can be stress through heavy weight, but it also should be the stress of heavy impact. And so it's very important that children engage in lots of high-impact activity because the physical force involved of impact, of jumping off of a two-foot-tall box, is much, much higher really than even can be put on with heavy weight-bearing exercises.

So both are important, heavy weight-bearing exercises and impact. But impact is that thing that continually creates little fractures in the bone, little micro fractures, and is the thing that can lead to growth. So in the "Growing Taller" episode, I focused on how you can grow your bones and grow taller due to that impact.

We talked briefly about the micro fractures and stretching them out even for growth of bone potential beyond puberty. That's not in any way accepted by medical science. It's something that the bros are trying out. And we'll tell if it works or not. But for young people, for children, this jumping is really important.

So everything you can have that involves jumping is important. Some of the things that I found that to work is, number one, children love to jump. Like it's super fun. So get yourself some plyo boxes, ideally some soft ones, and stretch them out. I find that my children love to jump up and down on the boxes and do the plyometric exercises.

They just think jumping is fun. And then I always make sure that they jump off the plyo boxes as well as jumping on to try to get as much impact as possible. And I build it up to the highest height possible. I've also been teaching my children to do parachute landing falls with the idea that, again, they can sustain higher levels of impact and encourage them to jump off repeatedly so that they build bones.

And then repetitive jumping exercise, things like jump ropes are amazing for the body. Just lots and lots of jumping, amazing for the muscles, amazing for the body. So get your children, especially your girls, jump ropes and get them on there every day. As with every other aspect of development we've considered here, the rule is this, everything in moderation.

Girls who over-exercise and get too skinny put themselves at risk for stress fractures. That's especially true for girls in track, gymnastics, and cheerleading. Too much of one kind of exercise without cross-training is not a good thing. As for eating right, forget everything you've learned from studies of boys or men.

Diet doesn't seem to matter as much in building boys' bones compared to girls'. Girls, for starters, must drink plenty of milk and avoid cola beverages. Consumption of cola beverages is linked to lower bone density and fractures in girls. This appears to be true of older women as well. Drinking soft drinks is associated with brittle bones in teenage girls, but not in teenage boys.

Girls who drink plenty of milk have stronger bones compared with girls who are equally well-nourished but who don't drink much milk. Other sources of calcium in the diet do not appear to be able to compensate for not drinking milk. There may be more to the story than just calcium.

Recent research suggests that there are some as-yet-unknown factors in milk that help to build strong bones, especially in girls. Soy milk, rice milk, and almond milk are increasingly popular. While some dairy farms are closing due to lack of demand for cow's milk, manufacturers of plant-based alternatives report difficulty keeping up with the surging appetite for their product.

I encounter parents who believe that these alternatives deliver nutritional benefits compared to real milk. Those parents are mistaken. One team of pediatricians reported cases of toddlers right here in the United States who showed signs of advanced malnutrition. Quasiorcor and Ricketts normally encountered only among severely impoverished families in the third world.

The parents were well-educated and caring. They thought they were doing the best thing for their child by giving their child soy milk or rice milk rather than actual milk. The authors note that it is misleading to use the term "milk" for these beverages. They prefer the term "soy beverage" rather than "soy milk." These authors note that the parents of one toddler assumed that they were providing their toddler with superior nutrition because of the fortified status and relatively high cost of the beverage.

But the beverage in question, like many rice, soy, or almond milks, provided less than one tenth the protein found in cow's milk, 1.7 grams of protein per liter, compared with 33 grams of protein per liter in cow's milk. Your daughter needs to drink milk. Milk from a cow. Or a goat.

Soy milk doesn't count. Almond milk doesn't count. If necessary, you could let her drink flavored milk. Girls who drink flavored milk do not become fatter than girls who drink unflavored milk. Girls who are lactose intolerant need to take special measures. So, give your 5-year-old daughter her very own little bottle of strawberry-flavored milk.

Don't wait until puberty. In one study, investigators measured bone density in 8-year-olds, then followed the children until they were 16 years old. Girls who had brittle bones at age 8 were significantly more likely to break their bones by the age of 16 compared with girls who had strong bones at age 8.

Let me add here just a couple of quick comments on the milk thing that may be helpful to some people. If your family is already a family of milk drinkers, great. What's interesting is that there are a lot of people who used to be milk drinkers that stopped. I was one of those.

When I was younger, we didn't have milk every day with every meal. That wasn't kind of the family culture, but I wasn't discouraged from drinking milk. I stopped drinking milk when I was in my teens because I decided that milk was making me fat and I was concerned about the impact of dairy on acne.

And so I stopped drinking milk because it was just too many calories and I didn't want to be fat. My wife didn't ever come from a milk-drinking family, and so we weren't in the habit of drinking milk. I also used to be super suspicious of conventionally raised milk. I got super suspicious of the hormone risks, the risks of all the hormones that the cows are given, and I got really worried about that.

And over the years, I became very suspicious of milk. I believe now that, again, my understanding as a layman, I believe that I was wrong to be as suspicious as I was back then. The hormones and other issues of things that I was worried about are not as big of a risk as I thought they were.

And milk should be something that should be consumed consistently. I used to make fun of the got milk ads about calcium also, about the bioavailability of calcium. I thought, well, there's things you read from the medical people about how the calcium doesn't get absorbed. And so I thought it was all a bunch of bunk.

I believe now that I was wrong. So I think we should encourage milk consumption. It seems to me that milk consumption, from what I understand, it's important to, whenever possible, pair milk consumption with vitamin D. Obviously, we want lots of sunshine, and so perhaps your body can create vitamin D, but most people are vitamin D deficient.

So taking a vitamin D supplement alongside the milk, as I understand it, is a very smart thing to do and really helps in the absorption of calcium. And it really does help our children's bones to grow better. And then in order to really be useful, it should be something that is served regularly.

So I grew up in a family where we never drank milk with meals, and I would go to some places where people would say, "Hey, would your children like milk?" And I was like, "No, we wouldn't like milk." I now think that children having milk with their meal is probably one of the best things that they can do to consume the protein, have the calcium, and have the calories that come from milk.

So you may have to deal with lactose issues separately. There are some people who have issues with that. What I do is make as much as possible raw milk. That's a separate controversial subject, but it seems persuasive to me, the benefits of raw milk as compared to pasteurized milk.

So if possible, get yourself a source of raw milk, but you do your own research on that and feed it consistently. So a little bit before every meal and get your children in the habit of that, especially your girls. It's really important. The current craze for soy milk here and almond milk there needs to be ended.

Oh, and by the way, milk is one of your cheapest sources of high quality calories that you can get. For your teenage boys who are trying to put on weight, while the GOMAD diet, the G-O-M-A-D gallon of milk a day diet is not the perfect thing, it's a time proven way for your teenage boys to bulk up.

The promise and perils of exercise. The evidence suggests that girls who are involved in sports are more likely to remain active through adolescence, when other girls generally become less active. Girls who are involved in vigorous physical activities, including but not limited to organized sports, also appear to be at lower risk for becoming depressed.

And that protective effect holds true regardless of body mass index or even fitness. In other words, an overweight girl who exercises regularly is less likely to become depressed than an equally heavy girl who doesn't exercise. And girls who exercise regularly are less likely to feel tired. Exercise has all sorts of benefits that have nothing to do with how much you weigh or how you look.

But some girls exercise too vigorously or for the wrong reasons. One study of girls age 9 to 16 found that 46% of girls want to look like a female celebrity. And that's part of the reason why they exercise. That's not a healthy motivation. It's other referenced rather than self referenced.

The goal should be to help girls have realistic and healthy body images and recognize the importance of physical activity for overall health and well-being, not just for appearance focused reasons. Lauren Fleshman is a veteran of collegiate sports. As an undergraduate at Stanford, she won five NCAA titles in track and field and was a 15 time All-American.

She observed firsthand other female athletes who were starving themselves. She blamed that on a sports system built by and for men. I certainly agree that when young women are coached by men who have had no training in the gender-specific strategies that work best for girls and women, and who may have inaccurate stereotyped beliefs about female athletes, such as the mistaken belief that female athletes must be rail thin in order to win, then bad things often happen.

Many girls are on the edge of an unhealthy obsession when it comes to exercise. Some girls fall over that edge. Obsessive exercise can be hazardous to your health. Researchers at San Diego State University interviewed girls at six different California high schools and found that 18% of girls playing interscholastic sports reported disordered eating attitudes or behaviors.

Almost one in four, 23.5%, had irregular menstrual periods. Almost as many girls, 21.8%, had low bone density. In another study, young women who participated in sports where leanness is desirable, sports such as gymnastics, were almost twice as likely to have irregular menstrual periods compared to young women participating at the same level of competition in sports such as softball, where leanness is not essential.

24.8% of girls in lean sports compared with 13.1% of girls in other sports. We discussed the athletic triad, the association of excessive exercise with brittle bones, disordered eating, and the loss of the menstrual period back in chapter three. I really want you to get this book and read it.

I'm not going to go back to chapter three. I'm already sharing an enormous amount here from this chapter on the body. But this topic of irregular menstruation for young women is enormously important. We are facing an absolute fertility crisis, and this particular factor of the impact of sports on regular menstruation for women is something that I find just in personal conversations with people struggling, with couples struggling with fertility, is fairly common and fairly prevalent.

And losing your fertilities to a stupid sport and becoming so excessively skinny that your body can no longer menstruate such that you have to spend tens of thousands of dollars in your 20s and 30s for every one of your babies seems to me one of the stupidest financial decisions that you can possibly make.

It's very annoying as a financial planner to end working with couples who aren't able to conceive babies naturally without external intervention. It's very annoying to have to reorganize the entire budget to spend tens of thousands of dollars for every baby conceived. That makes the cost of having children enormous, and it wrecks all kinds of other things.

And a significant component of it can be avoided through information and proper practice. So don't let your daughters get so skinny that their bodies stop working. It's absurd and it has to end. On the one hand, you don't want your daughter to obsess about her weight. On the other hand, girls who are out of shape are at greater risk not only for overweight and obesity, but also for depression and fatigue.

How can you encourage the right kind of healthy exercise without pushing your daughter over the edge? In order to answer those questions, we need to understand the role that culture plays and the role played by something psychologists call social contrast effects. What do girls in Chicago have in common with Hopi girls in Arizona?

Carol Cronin-Weisfeld and her colleagues wanted to understand how much of the difference in girls' and boys' interest in sports is due to culture, and how much might be due to other factors, perhaps psychological rather than cultural. They decided to watch girls in Chicago playing dodgeball, first girls against girls, then girls and boys together.

Then they did the same thing with Native American children on a Hopi reservation in Arizona. When Chicago girls played against other Chicago girls, there was lots of variation in the style and quality of play. Some of the girls were really serious about the game. As soon as play began, those girls would adopt what coaches call the "athletic stance" – knees bent, arms flexed, eyes focused, ready to jump for the ball.

When play got underway, these girls were real competitors. They would jump for the ball, grab it, sometimes even wrestling the ball away from another girl. The girls who were most engaged were, not surprisingly, the highest skilled girls at playing the game. Other girls were not particularly excited about the game, and certainly were not jumping and grabbing for the ball.

Again, not surprisingly, these girls were less skilled. Weisfeld and colleagues found the same variation in engagement and skill among the Native American girls in Arizona. When boys were brought into the gym, so that there were an equal number of girls and boys playing, the picture changed dramatically. The Hopi girls still participated in the game, but the high-skilled girls no longer demonstrated their skill.

They didn't want to fight the boys for the ball. When the boys were playing, the high-skilled Hopi girls looked very much like the low-skilled girls. Most of the high-skilled Chicago girls didn't even hang around for the game when boys were playing. Instead, they left the playing area altogether and went off in little groups to dance with one another or to snack on potato chips.

Most of these kids, girls and boys, were 12 years old. In this study, the average girl in Chicago and in Arizona was bigger and taller than the average boy in Chicago and in Arizona, respectively. Which is not surprising because 12-year-old girls are often bigger and taller than 12-year-old boys.

Nevertheless, the high-skilled girls seemed to lose much of their enthusiasm for the game when boys came on the court. In a peculiar twist, the investigators, who had previously rated the skill of each girl and each boy in single-sex competition, arranged a game in which high-skilled girls played against low-skilled boys.

The girls didn't do well. They didn't try hard. Only one Chicago girl and only one Hopi girl seemed to be comfortable fighting the boys for the ball. This study illustrates what psychologists call "group contrast effects." When members of two different groups are present, members of each group tend to exaggerate the differences between the two groups.

Boys and girls categorize themselves as "boys" and "girls," respectively, and will be more likely to behave according to the prevailing cultural stereotype. When girls are around, boys are less willing to exhibit any behavior that might be considered feminine. When boys are around, girls are reluctant to exhibit behaviors that might be considered "boyish." I've seen this phenomenon myself while visiting co-ed schools and single-sex schools with regard to displays of affection for the teacher, for example.

At co-ed elementary and middle schools, it's common to find girls giving the teacher hugs. But you won't find many boys hugging the teacher. At co-ed schools, hugging the teacher is something girls do. But if that school adopts the single-sex format, with boys in all-boys classrooms, all of a sudden you'll find boys hugging the teacher as though it's the most natural thing in the world for a boy to do, which, of course, it is, as long as there aren't any girls around.

Likewise, in the study of Hopi girls and Chicago girls, if grabbing the ball out of somebody else's hands is perceived as something boys do, then girls will be less likely to do that if boys are present. When the girls are by themselves, you see a wider range of individual differences, from the competitive athlete to the disengaged girl.

When boys are added into the mix, group contrast effects kick in, and many of the girls act more "girly," less competitive, more talkative. The co-ed format, especially in sports, has the effect of homogenizing the girls. Variations among the girls diminish, and differences between the sexes are exaggerated. And here's what I found strangest of all about the Chicago, Arizona study.

When the investigators asked the girls which format they preferred, all-girls or co-ed, the girls in both locations overwhelmingly said that they preferred the co-ed format, even though the video showed clearly that the girls were less engaged and did much less well when the boys were playing. That's important. Asking girls which format they prefer isn't a reliable indicator of which format is actually best for them in terms of athletic engagement.

What girls say they prefer may not always be what is best for them. Nowadays, it wouldn't be cool for most girls to say, "No, I would prefer to do my physical exercise just with other girls, no boys." Such a comment might make a girl vulnerable to the charge of being, God forbid, a prude.

But there's good reason to believe that for most girls, particularly after the onset of puberty, the all-girls format is usually preferable for physical activity. Part of this has to do with the "swimsuit becomes you" phenomenon we considered in chapter 1. "When the boys are around, you can feel them looking at you," one girl said.

Some girls might worry about how they look in the eyes of the boys. Other girls are simply annoyed by the way boys rate girls' bodies, as some boys do. There is some evidence that girls from kindergarten through high school are more likely to exercise when offered a single-sex gym class rather than a co-ed class.

Before 1980, it was common for girls and boys to take their physical education classes separately, even if all other classes were mixed. Today, most co-ed schools in the United States have co-ed PE classes. There are many other reasons why this may not be such a good idea beyond the changes just discussed.

The best way to provide instruction in physical education may be different for girls than it is for boys. For example, one strategy that is often effective for girls is to have one girl, more experienced in the sport, teach the sport to a novice girl. The more experienced girl is more likely to be sensitive to the needs of the less experienced girl and more interested in really helping her to learn the sport.

Girls seem more interested in sharing their knowledge for the sake of sharing, whereas boys are generally more interested in showing off. So this strategy, pairing older kids one-on-one with younger kids, works less well for boys. The reasons kids play sports are often different for girls than boys. For many boys, the thrill of victory and the agony of defeat is what sports are all about.

But many girls may be more interested in developing their personal capacities through sport than they are in establishing personal superiority over others, according to a report from researchers at the University of Montana. Many boys engage in sports because they want to win. The best way to get them engaged in a PE class is to have a real game with clearly defined winners and losers.

Though some girls have that same competitive drive, for other girls, a win-at-all-costs mentality may be less appealing and may even push them away from sports. Girls are, on average, more likely to enjoy sports when the emphasis is on having fun and getting in shape rather than on beating the other team.

You can begin to appreciate how a physical education program with girls and boys in the same gym class might result in zero-sum choices for the instructor. If you, the instructor, organize a winner-takes-all competition, then you may engage many of the boys, but you risk disengaging many of the girls.

But if you structure the class along the lines of "everybody gets a trophy, everybody's a winner," then you may lose at least some of the boys. The single-sex format can broaden horizons for boys as well as for girls. Again, group contrast effects may be part of the explanation. Several years ago, I was interviewing a boy at an all-boys school in Perth, Western Australia.

I asked him whether he saw any advantages to attending a boys' school. Was he doing anything at the boys' school that he wouldn't be doing at a comparable co-ed school? "Ballet," he responded without hesitation. This young man was the top football player at the school. We're talking Australian rules football, of course.

He was tall and muscular. But there's no way I'd do it if the classes were mixed. He explained that when it's just guys in the ballet studio, and some of those guys are his teammates, then it's okay to work on balance and poise and fourth position. If girls were around, you wouldn't feel as comfortable doing a deep plie, I asked.

He shook his head. "I just wouldn't be there," he said. By the way, just to insert, this happened to me. When I was in college, I tried to press myself to do different things. So I took a salsa dancing class, which was great, super fun. And I had a friend of mine who was an amazingly athletic, coordinated guy, and he was a dancer.

He did ballet. And I had always judged ballet as something stupid and girly and never going to be involved. Then I started researching the topic of ballet, and I discovered, "Wait a second. This is amazingly athletic. And you look at male ballet dancers, they're just incredible athletes." And so I thought, "Well, Joshua, you want to get some exercise.

You want to get stronger and whatnot. Why not? Let's try it out." So I signed up for a ballet class, and I went the first day. And it was a mixed ballet class, and I walked out the door. I never could come back, because everything about it, where I was always happy to...

I have no problem being a total novice at something. I have no problem being terrible at something. I'm pretty good at that. I don't have a lot of pride associated with that stuff. Just get in and start learning it. But in a mixed class format of ballet, where you're just terrible at it as a guy, I could not do it.

I couldn't do it in front of girls. Whereas if it had been a male-only ballet class, I probably would have done it and learned something and gotten flexible and learned to dance, and it would have been good for my overall athletic development. So I would concur with what that guy said.

I have found that parents are often receptive to the idea of single-sex physical education for teenagers, provided that the same facilities and resources are available to the girls and boys. That willingness seems to arise in part because so many parents are concerned about the sexual overtones that might kick in when teenage girls and boys engage in strenuous physical activity in close proximity.

Too much heavy breathing. But many parents balk at the idea of single-sex physical education for younger kids. I don't see the point of separating girls and boys for gym class in second grade, one parent told me. Seven-year-olds don't have a sexual agenda at that age, do they? She asked.

Seven-year-olds hopefully do not have a sexual agenda, but they certainly do have gendered notions about physical activity. As I noted earlier, seven-year-old boys are more likely to boast about their imaginary physical prowess, and seven-year-old girls may believe them. So girls get the notion very early that the gym and the playing field are the boys' domain.

An all-girls physical education program, beginning in kindergarten, might enable more girls to take ownership of the whole domain of physical activity. We need to help our daughters take that ownership, to feel comfortable on the playing field. By the time kids reach adolescence, boys are much more comfortable than girls on basketball courts, playing fields, streets, local parks, and other public spaces conducive to physical activity, according to researcher Dr.

Candy James. Girls often see these places as belonging to boys, and they fear being teased, excluded, or hurt if they try to join in. Instead, they sit on the periphery as passive spectators or avoid these active spaces altogether. Many of the girls surveyed by Dr. James said they would use their school basketball courts if the courts were located where boys could not watch them.

Work with your school to ensure that all-girls athletic options and all-girls physical education are available. But the all-girls format won't be so great if you have a male instructor screaming at the girls. We parents need to insist that the instructors who are teaching our daughters understand and respect gender differences in order to help each girl to fulfill her physical potential.

In her book, Perfect Girls, Starving Daughters, Courtney Martin describes her own years-long struggle to accept her body, to move beyond her obsession with what she ate and how she looked. Her body was her enemy. She began to glimpse a resolution to her struggle one day while taking a yoga class.

The instructor told her to "meet your body where it is." This was a new concept for her. Meet your body where it is. Be comfortable in your body. Work on your fitness, but be at home in your own body. Psychologist Madeline Levine writes that many communities overvalue a very narrow range of academic and extracurricular accomplishments.

Many parents sign their daughters up for soccer or basketball without investigating whether those sports are really the best choice for their daughter. For some girls, yoga or aerobics might be a better way of connecting with their own bodies. Or maybe canoeing. I recall Shannon, a teenage girl from my own practice, who discovered on her own at the age of 13 that she had a passion for canoeing and kayaking.

Her father asked if she wanted to join a kayaking club so that she could compete against other teenagers. She had no interest in competing. She didn't want to beat anybody. She just enjoyed the feeling of being on the river, gliding along the water on her own power. During the summer between 10th and 11th grade, Shannon spent two weeks canoeing the Snake River in the Yukon Territory, Canada, with a group of other girls.

She told me later how much she valued that experience. "We spent all day every day either canoeing or portaging our canoe. By the time it was evening and time to make camp, I was so hungry. You can't believe how good fresh river trout tastes after you've spent six hours canoeing and two hours portaging your canoe and your gear." Then after a pause, she said, "It's the most spiritual thing I've ever done.

Out there in the wilderness, on the river, where there's no trace of anything human, it's so easy to believe in something more. Paddling on the river became a kind of prayer for me, you know?" I nodded, because that's what doctors do, but I wasn't sure I understood. "The physical becomes spiritual," Shannon said, and then shook her head as though she had said something wrong, or as though she were on the brink of tears.

And thus concludes chapter six of the book Girls on the Edge by Dr. Leonard Sachs. I would commend it to you. It's a great book. His book, Boys Adrift, was one that a listener begged me to read, sent me multiple emails until I finally acquiesced, and then I went ahead and found it so good that I followed on with Girls on the Edge.

There are other, I'm sure, other books, and I'm sure there's controversy about all that stuff that he said. Who knows? The point is, recognize that your girls need to develop their bodies, just like boys need to develop their height. And if you are able to raise daughters who are strong, who are athletic, who are comfortable in their bodies, and who have strong athletic bodies themselves, that confidence will probably have a similar effect to the confidence that boys come with height.

Now, I can't prove any of that. And we go back to the question of, are people, tall people, do they make more money because of heightism and kind of a social perception, or is it a cognitive thing? Again, the researchers, some of them claim that height is indicative of cognitive development, so probably it's that tall people are slightly smarter than people who are not tall.

I don't know. All I know is that all of us are attracted to strong and confident women. And so if we want our daughters to become strong and confident women, then we need to think about the environment that they're raised in and think about how do we nurture strength and confidence?

It's not the only thing. There are many other things, everything from social abilities and character qualities and physical appearance and kindness and all kinds of other factors, but we need to give careful attention to it. So I didn't want to just ignore the girls in that particular episode. I want you to know that we need to make certain of physical development for both our boys and our girls, but that we need to be certain that we don't let our androgynous culture that claims that there's no differences between boys and girls keep us from doing what's right.

Undoubtedly, if you take this message and go to your local institutions, unless your institutions are enlightened, undoubtedly, you're going to immediately get in the thick of the swamp with, "We can't treat boys different from girls. We can't treat girls different from boys." Don't let it... Again, I described earlier, if my Christian homeschool co-op isn't, if the moms in there are not willing to consider having boys-only classes or girls-only classes, not even willing to consider it, then you're probably going to face similar levels of resistance, no matter in your institution.

But that doesn't matter. What matters is, is it true or is it not true? And then if it's true, then for the sake of those we love, you and I have a responsibility to press in, fulfill our responsibilities as leaders of society, and do what is in the best interest of our children, regardless of whether it's popular or not.

So, I hope these ideas have helped you, and I hope that you have a great day. I'll be back with you soon. Heading back to school is a breeze, and so are the savings at your local AmazonFresh grocery store. Our favorite class? Lunch. Plan, prep, and pack in one convenient place.

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