How to Know If You Need a Rest Day | Dr. Andy Galpin & Dr. Andrew Huberman
00:00:00.000 | How should people think about systemic damage and recovery?
00:00:07.000 | Because obviously the nervous system and the way it interacts with the neuromuscular system
00:00:11.760 | is the site of all the action here, or at least a lot of the action.
00:00:17.440 | And the nervous system can in fact become fatigued.
00:00:20.240 | It has a great capacity, but the whole system that we're talking about can be worked to
00:00:26.720 | the extent that even if a muscle group, like the biceps or the back, is being allowed to
00:00:31.320 | rest while you're training legs and other muscle groups, that your whole neuromuscular
00:00:35.360 | system needs rest.
00:00:37.400 | How does one determine whether or not your entire body needs complete rest, or low-level
00:00:42.160 | active rest, or exercise of a different kind?
00:00:44.280 | Yeah, yeah, sure.
00:00:45.280 | So I want to actually tackle this because we're on the topic of hypertrophy.
00:00:48.320 | I'm assuming that that's the goal in mind here.
00:00:51.040 | Yes, here I'm asking specifically within the context of hypertrophy.
00:00:54.080 | I realize that for other training goals the answer to this question could be quite different.
00:00:58.120 | Yeah, okay.
00:00:59.120 | So we actually do this in a couple of different ways.
00:01:00.120 | Let's start local and work back to systemic, right?
00:01:02.240 | Because number one, what you're really concerned about is at the local muscle level is am I
00:01:08.840 | going to create excessive damage?
00:01:11.280 | And I don't necessarily mean muscle damage here, I mean injury, right?
00:01:13.840 | So the kind of rule of thumb we use is like three out of ten in terms of soreness.
00:01:17.200 | If you're more than three out of ten in terms of soreness, we're going to start asking
00:01:21.680 | questions.
00:01:22.680 | If you're six out of ten, we're probably not training.
00:01:25.320 | This is a subjective measure.
00:01:26.320 | Total subjective measure, right?
00:01:27.960 | And you'll know very quickly, right?
00:01:29.720 | If you can barely graze your pec with your fingertip and then you're like, "Ah, I don't
00:01:34.720 | care what you score that, we're not training.
00:01:36.520 | There's just no damage."
00:01:37.640 | If you're three out of ten, if you're just like, "Oh, I'm kind of like a little bit stiff
00:01:41.000 | here," but once you get warmed up you start feeling okay, you're probably okay to proceed
00:01:45.320 | there.
00:01:46.320 | So that is a very easy way to just think about soreness.
00:01:50.320 | You're going to be a little bit tight depending on your training frequency.
00:01:53.240 | Now zooming out to systemic, we use a whole host of things.
00:01:56.040 | So we actually have a whole host of biomarkers we use.
00:01:59.280 | You can get a lot of these from blood.
00:02:00.280 | So you can look at things like creatine kinase, that's the very common one marker of muscle
00:02:04.280 | damage.
00:02:05.280 | We'll actually look at LDH, we'll look at myoglobulin.
00:02:09.560 | That's just like—if you think about hemoglobin is the molecule that carries oxygen throughout
00:02:14.520 | your blood.
00:02:15.520 | The myoglobin is the part of that that's actually in muscle.
00:02:18.360 | So when muscle gets broken down, that gets leaked out and put in your blood.
00:02:21.000 | That's one of the markers actually that's going to be associated with things like rhabdo,
00:02:24.400 | which is like you're going to see your urine is purple and it's extremely dark because
00:02:28.320 | you've got so much muscle breakdown that happens and kidneys can have a problem and you put
00:02:32.280 | a bunch of stuff in there.
00:02:33.280 | So we use those biomarkers.
00:02:34.280 | We'll actually also look at probably a couple of things you're familiar with, ALT and ASD.
00:02:39.160 | These are excellent biomarkers of muscle breakdown.
00:02:41.200 | So if we are actually suspecting that this is a chronic problem, we're going to actually
00:02:45.200 | go in and pull some blood.
00:02:47.640 | If it's just like I'm super sore today, we're going to use that subjective marker.
00:02:50.560 | But if we're seeing this as constant, like man, are we really pushing you way too much,
00:02:53.920 | is there some sort of systemic problem, we're going to blood and we're going to look at
00:02:57.160 | all those different things.
00:02:58.160 | Now, AST to ALT is really specific and I don't want to take us too far off track here, but
00:03:03.200 | the ratio to those things is actually very important as well.
00:03:05.560 | So if you look at the AST to ALT ratio, typically the number we'll look at is like 1.67.
00:03:10.840 | As that ratio is like higher than that, you have a pretty high risk of muscle damage.
00:03:14.000 | But really between, you know, me and you and a few of these listeners, any time we start
00:03:19.840 | seeing AST outkick ALT, we're immediately thinking, as in the ratio being higher than
00:03:24.200 | 1, we're immediately thinking like there's something happening muscle damage-wise.
00:03:27.840 | So that's actually a sneaky good indicator of just total muscle mass, because the vast
00:03:31.880 | majority of that's going to be in muscle.
00:03:33.760 | So those are actually some markers that we like a lot if muscle damage is the thing we're
00:03:39.120 | concerned with.
00:03:40.160 | If we are more concerned with things like total training volume, systemic overload,
00:03:45.080 | then we may turn to something more like sleep.
00:03:48.000 | There's a lot of information we can actually glean from changes in sleep behavior and function.
00:03:53.440 | You can also look at things like HRV, heart rate variability, which is a very classic
00:03:57.280 | marker and much more sensitive to changes with training than something like a resting
00:04:01.760 | heart rate, which is one thing you can actually do that's totally cost-free.
00:04:05.560 | Just look at your changes and any elevation resting heart rate over time, especially more
00:04:11.120 | than three to five consecutive days is an indicator.
00:04:14.080 | But HRV is much more sensitive to things like training-induced overload.
00:04:18.600 | So that's a quick version of stuff that we're going to pay attention to.
00:04:21.520 | The last one I would add there is simply motivation.
00:04:25.000 | So if you're really training hard and you like training hard and you just like cannot
00:04:28.100 | force yourself to go anymore, that in and of itself can be a good indication of it's
00:04:32.360 | maybe not the day, maybe not the week.
00:04:34.800 | With all of these things, you want to be careful about overreacting to a single day measure.
00:04:40.040 | Again, we need to look at at least a trend of more than three days.
00:04:44.040 | Honestly, I'm looking at more than five days.
00:04:45.920 | I'm going to pull back from that and think about what phase of training we're in, what
00:04:50.160 | part of the year we're in, typically whether it's in-season, pre-season, post-season, off-season,
00:04:54.560 | et cetera, to make our decision about what we're going to do about it.
00:04:57.680 | Are we canning the entire workout?
00:04:59.320 | Are we doing a modified, lower version, lower intensity?
00:05:02.720 | My default generally, if hypertrophy is the goal, remember, volume is the driver there.
00:05:09.200 | So if I can, like can we get in, can we go real light, let's go to six out of ten RPE.
00:05:15.160 | So relative perceived exertion.
00:05:17.480 | Maybe we'll reduce the range of motion.
00:05:19.640 | Maybe we'll make it a little bit easier.
00:05:21.840 | Maybe go to machines or instead of going to squat, we'll just do leg extension or something
00:05:26.640 | like that.
00:05:27.640 | But I want to still get enough volume in there.
00:05:29.080 | That will keep you on target, and again, even going at 50%, not to high repetition, 50%
00:05:35.480 | for a set of ten, three sets.
00:05:36.800 | Just get a nice blood flow in there, get it in, get it out, aid in recovery, and then
00:05:41.000 | move on and come back the next day.
00:05:42.400 | That's probably what I would do rather than canning the entire session.
00:05:45.600 | [Music]