Jeremy Ethier breaks down what happens to your muscles when you stop training. Most loss in the first two weeks is water and glycogen, not actual muscle. True atrophy starts after three weeks, but you can slow it by eating enough protein, maintaining calories, and doing light resistance work.
Questions this video answers
Up to 1 kilogram
11%
About 16%
Around 20%
After about 3 weeks of no training
For the majority of lifters, it's likely that at some point you've had to take some time away from training, whether it's due to injury, evocation or life just getting in the way. And it's also likely that during this time off you've been concerned about losing muscle and sabotaging all the recent progress you've been making in the gym. But how fast do you actually start to lose your hard earned size? Well, unfortunately, it can happen pretty quickly. For example, one 2013 literature review found that you can lose up to a kilogram of lean body mass in just a week when you're fully immobilized and even when you're not fully immobilized. Research has shown an 11% decrease in type 2 muscle size in trained subjects after just 10 days of no exercise. But before you freak out, it's important to note that this decrease in size is for the most part not due to actual muscle loss. It's instead due to a drop in glycogen levels and water stores within your muscle, which which makes a significant difference in how big your muscles appear. In fact, research shows that muscle glycogen can increase muscle volume by about 16%. And since research also shows that when you stop training, your muscle glycogen levels can drop by 20% after just one week, it means that your muscles will look considerably smaller after some time away from the gym, which is something you've probably noticed yourself. But the good news is your muscle glycogen levels and water stores will quickly refill once you start training again. In fact, one 2013 study from the University of Tokyo illustrates this idea and found that subjects who trained intermittently with six weeks on and three weeks off for a total length of 24 weeks gained virtually the same amount of muscle as subjects who trained continuously for the 24 weeks. The only major difference, as shown here, was that the muscle size with the intermittent group fluctuated quite a bit due to increases and decreases in glycogen in the muscle corresponding to their on and off periods. Simply meaning that taking a couple weeks off from the gym won't cause any significant muscle loss, even though it may seem like it due to your glycogen and water fluctuations. However, this doesn't hold true forever because as shown in this 2013 literature review, after three weeks of no training is when you'll indeed start to experience actual muscle and strength loss. But luckily, if you are planning on taking extended time away from the gym or are just going to be very inconsistent with your training for a while. Then there are a few things you can do to hold on to whatever gains you can, and that's exactly what I'll cover in this video. Your body's ability to maintain its muscle mass and current body composition is strongly affected by how much you eat. And this is especially true in the event that you're not training. Although eating at a calorie surplus is normally helpful to build muscle, since you're not actually training, it's simply going to result in a excessive fat gain instead. And on the other hand, although eating at a calorie deficit is normally helpful to lose fat, again since you're not actually training, it's going to contribute to increased muscle breakdown. Therefore, your best bet is to eat enough to just maintain your weight. And research is in agreement with this. For example, this 2013 literature review analyzed the effect of eating at a calorie deficit maintenance calories or a calorie surplus for muscle mass retention in subjects taking a break from training. As expected, they found that a calorie deficit led to the greatest amount of muscle loss. And what's interesting is that they found that eating at a calorie surplus actually led to not only fat gain, but also increased the rate of muscle loss, which they speculated was due to a variety of processes that occur from the fat gain. So again, as recommended by the researchers, simply stick to maintenance calories and to quickly get a rough estimate of what that is for you, I'd recommend simply multiplying your current body weight in pounds by 15 and sticking to that while keeping track of your weight over time. Now, your next priority should be to ensure that you're eating enough protein every day. Since as expected, research suggests that maintaining a high protein intake during a period of no training helps minimize muscle loss. Now, as for the exact amount, we know that sticking to a protein intake of roughly 0.73 to 1 gram per pound of body weight is sufficient. But just to be safe, in your case, sticking to the higher end of this range would likely be your best bet to maintain as much muscle mass as possible. And lastly, it's important to realize that strength training isn't the only kind of exercise that can maintain muscle mass. Simple activities like brisk walking, light swimming, or doing chores, for example, is enough stimulus to help you maintain your muscle better than you would if you were completely sedentary. And in addition, during your time off, if you are able to make it to the gym at all, multiple studies have indicated you actually don't need to do much in order to maintain your muscle mass. For example, this 2011 paper found that you only need around 1/3 of your original training volume to maintain muscle mass. Similarly, this 2018 paper by Schoenfeld and colleagues found that subjects who performed the following 13 minute workout just three times a week were able to maintain and even slightly increase their muscle mass throughout a period of eight weeks, simply meaning that anything is better than nothing. So if you have the time to make it to the gym for one full body workout per week or multiple shorter full body workouts per week, this in conjunction with the previous tips mentioned, will be more than likely enough for you to maintain your muscle mass. And if you're unable to do so due to injury or whatever reason, don't stress out about it. And definitely don't try to train through your injury as this often just works, worsens it and makes it take a lot longer to fully recover from. And besides, muscle memory is a very powerful and proven phenomenon, meaning that any muscle and strength you do lose will be very quickly regained once you get back to your regular routine.
That's pretty much it for the video everyone. Thank you so much for watching. I hope you enjoyed it. And as always, if you're looking for a truly evidence based program that basically combines all the research I do into an easy to follow system to transform your body, then simply head on over to buildwithscience.com forward/courses where you can choose the best program for you. I'd also really appreciate it if you gave me a follow on Instagram as well where you can stay updated with what I'm doing and see a lot of the informative content that I post there on a more regular basis. And lastly, if you enjoyed this video then please don't forget to give it a like leave a comment down below, subscribe to my channel and hit that notification bell as well as this all really does help me out. Anyways, that's it for today. Thank you all so much for your continued support. I really do appreciate it and I hope you've been enjoying my content. I'll see you next time.
