Scientists on building muscle: what it takes for growth

Mr. Kleinöder, Muscles look good. Visuals aside, why should we train them?
Looking good is one thing. And it’s a matter of taste whether you want more or less of it. There are sports in which the muscles should be thickened – especially bodybuilding. The balancing act to become a ski jumper, who primarily needs functional muscles, is a big one. Muscle training prepares you for the stress of sport and serves as injury prevention.

And outside of competitive sports?
Muscles can serve a wide spectrum. Among other things, we benefit from them psychologically and have more self-confidence. They ensure a better quality of life overall. This is particularly important in old age. So that people can still stand up on their own, bend down and take part in life. Muscles give us more strength and therefore security.

Many people want more muscles. But how do we build them?
When we do strength training, we train the muscle and thereby give it an intense stimulus and tire it out. Micro-tears occur in the muscles, which can become noticeable as muscle soreness depending on the intensity. The body repairs the small injuries itself during regeneration phases and the muscle thickens. He is preparing for the next challenge. However, muscle growth only becomes visible after about four to six weeks.

How do I have to train for this?
Let’s put ourselves in the shoes of the muscle. He can’t count how many reps we do. He is primarily interested in how much tension he gets, how long it lasts and how regularly he gets it. A certain number of repetitions is just one tool. In the end, the muscle must above all be fully utilized. Over time, you can gradually increase the repetitions and weight until you reach your maximum strength range. Just please use doses and don’t overdo it with the intensity.

Otherwise?
If I strain my stress reserve too much, sooner or later the entire body system will suffer. The muscle and other structures need time to adapt.

Finding the right size is sometimes not that easy.
That’s correct. But anything beyond strength training four times a week no longer has much to do with health. I should pay attention to how my muscles feel and only go back to training when I’m rested. When I feel “hungry” again and want to exercise.

So is strength training the best way to build muscle?
It’s the classic way, but we also build muscle in other sports. In contrast to training in the gym, building muscle is more functional and sometimes less systematic – for example, a tennis player’s hitting arm is significantly thicker than the other arm. Systematic building is more about bringing the muscles into equilibrium and balancing them so that the body functions well.

How important is lifestyle outside of the gym?
Very important. Many factors play a role – nutrition for example. If the muscle does not receive protein promptly after training, for example, it will have a harder time adapting. And if sleep, an important part of regeneration, is missing, that’s not optimal either. That means: Training is just the trigger. We have to create additional conditions for building muscle around it.

What does “promptly” mean in relation to protein intake?
Best within the first hour. If it takes too long to eat, you can also drink a protein shake in the meantime so that the substances the muscle needs to build are available.

What else should you pay attention to when it comes to nutrition?
In general, it is recommended to eat enough fruit and vegetables. A healthy mixed diet is the basis. Actually, you don’t need anything special. However, you should avoid foods with so-called “empty” calories if possible. For example, very sugary foods like pudding.

What do you need before training?
It is best to prepare the muscle so that it is charged with energy. So you should eat carbohydrates and, if possible, not rush home from work.

And it doesn’t matter whether you eat meat, are vegetarian or even vegan?
All of these diets are compatible with building muscle. Vegetarians can use dairy products as a source of protein instead of meat. Vegans have to get their proteins from legumes or similar and, if necessary, supplement certain vitamins because the need increases due to strength training.

Why is sleep important for building muscle but stress is counterproductive?
Sleep is needed to start the regenerative processes. When we do strength training, we not only address the muscles, but also the metabolism, tendons, ligaments, bones and much more. So we need rest so that all systems can recover. And those who are stressed usually don’t sleep well.

Does alcohol endanger muscle growth?
To build muscle we need to perform coordinated movements. This is particularly neurally demanding when doing exercises with free weights. If you drink alcohol the evening before training, you will lose precision the next day. The risk of injury increases. And anyone who drinks after training has a harder time recovering. Alcohol damages the neural system and therefore also training. Leaving it out completely is perhaps utopian. But in combination with training, you should drink in moderation.

How does muscle building differ between men and women?
From the age of eleven or twelve, the gap between boys and girls widens dramatically. Boys then have 30 to 40 percent more strength due to muscle growth. The male hormone testosterone provides this booster effect. For some more, for others less. And women have cycle-related phases in which they have more or less energy during training. This then influences muscle building either positively or negatively.

From your perspective as a training scientist: Which assumptions regarding muscle building are wrong?
If done correctly, strength training is not dangerous for children and teenagers. Parents often fear that it will harm their children’s bodies. It prepares your muscles for popular sports. Because the strength required in football, athletics, gymnastics and other sports is much higher. Strength training is primarily used for prevention.

And what about the adults?
Some people shy away from building muscle and say, “I don’t want to look like Arnold Schwarzenegger.” There is a great lack of understanding behind this. To get such a body requires years of effort and torment as well as the appropriate genetic requirements. If necessary, illegal substances such as anabolic steroids, which have numerous negative effects on health, are used to support muscle building. So normal people don’t have to worry about this.