Gyms are on the verge of reopening their doors, which means that we may soon be united with a long lost muscle building friend: heavy lifting. Unfortunately not everyone has been able to keep up a rigorous training routine throughout the lockdown, so many are wondering: will I have to start all over?  We've had a look at the latest research, and we're glad to conclude that your hard-earned muscles stick to your body much more loyally than you may think. In fact, you may have very well progressed in spite of the abstinence from heavy weights. Allow us to elaborate.

What happens to your muscles when you don't do anything

It takes a serious stretch of inactivity before you'll really lose large amounts of muscle mass. And by inactivity we mean it in the absolute sense, such as during prolonged hospitalization or when one of your limbs is immobilized in a cast. Research among healthy subjects has shown that just one week of bed rest can already lead to a loss of 1.4 kg of muscle mass and a significant loss of muscle strength (-8%). However, we assume that you haven't spent your quarantine days immobilized in bed, so let's have a look at a few slightly less dramatic scenarios.

What happens when you skip a few weeks of training

When you are habitually strength training, a short break does not seem to have a major impact on your muscle mass and strength. We know what you're thinking: 'Yeah, right. The mirror tells me otherwise!''. This may be true in the sense that not training for a few weeks can reduce the amount of carbohydrate (glycogen) stored in your muscle. 1 gram of glycogen can bind up to 3 grams of water, so a period of detraining may reduce your glycogen supply and thus make for a less 'swollen' muscle. Most of the volume you think you lose in the first weeks can therefore probably be attributed to fluid loss in the muscle, and not to loss of actual muscle mass. Incidentally, a recent study of trained men showed that during two weeks of detraining there were no measurable changes in muscle mass. Good to know, but of course we would like to hold on to our muscle for a little longer than two weeks. So what does that take?

What happens when you train less for months on end

‍Scientific research has shown that maintaining muscle mass requires much less training than actually building it up. For example, one study showed that muscle mass built up by performing 27 sets per week for 4 months required only 3 sets per week in young men (20-35 y.o.) and 9 sets per week in older men (60-has 75 y.o.) to maintain. And this was over a period of 8 months! So if you are satisfied with your level of muscularity, it doesn't take much to maintain it. But how would you be able to achieve this when bread-and-butter heavy lifting is still out of the picture?

Higher reps with lighter weights may work

In recent years, quite some research has been conducted regarding the role of training with light (30-50% 1RM) versus heavy weights (70-90% 1RM). This research shows that your muscles can be stimulated to increase muscle protein synthesis and ultimately grow muscle mass regardless of the amount of weight. What turns out to be important is that with each performed set you get as close to the point of total exhaustion ('failure') as possible. With a heavy weight this of course happens faster and is therefore easier to achieve, but with a light weight this can simply be achieved by performing more repetitions. So in a way you could get the same results with lighter weights, and you won't have to perform more sets than you normally would with a heavier weight.

Bodyweight movements are also effective

Not being able to bench press or squat with heavy weights for a while is also no problem. As an indication: the aforementioned 70-90% 1RM would correspond with weights that you can lift for about 3 to 12 reps per set - numbers quite familiar to the seasoned strength athlete. On the other hand, the lower percentages of 30-50% 1RM would be weights that you can lift for 30+ reps per set. This is very good news for those who are still training on an improvised home-kit. Because where training with 90% 1RM (+/- 3 rep max) is quite impossible if you don't have a barbell with a serious stack of plates at your disposal, sets of 30 reps are very workable when training with only body weight or limited resistance. Even for the strongest among us.

Conclusion

Knowing that maintaining muscle mass is a lot easier than building it up will hopefully reassure many. Especially considering the fact that periodically training with lighter weights and higher repetitions may very well lead to additional muscle growth. So don't sweat the lack of heavy lifting too much, focus on what you can do, and you may soon return to the gym with even more muscle than before.

Good luck!

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