Beware of the gym bros: Science debunks the myths of strength training gurus

Who hasn’t had the feeling of being completely ignorant about strength training when starting to go to the gym? It is enhanced when talking to gym-bros or crossfitters, who pass themselves off as experts on turning fat into muscle and hypertrophying even the smallest muscle in the body. But do their good intentions reflect scientific knowledge or just popular opinions? The latter could lead to injury, while with the former allows us to exercise properly. Let’s take a look at some of the most widespread myths in the gym.

A gym bro will tell you to be careful when you stop training, because muscle can turn into fat. Nothing is further from the truth. Scientific evidence is clear in this regard: fat and muscle are tissues with different structures and functions. Muscle is made up of muscle fibers that can increase in size (hypertrophy) with scheduled training, and decrease in size if training ceases (hypotrophy). Fat cells (adipocytes) can increase in size when there is an increase in caloric intake. What often happens is that the gym-bro consumes more calories when training, compensating for their caloric expenditure due to exercise, but when they stop training, they continue to consume the same amount of calories, therefore generating an increase in fat cells as the period of inactivity progresses.

The gym-bros will always have a clear six-pack, pointing out the best exercises to mark and define the abs and differentiating between various regions. But it is possible to perform exercises with an incorrect position or movement, which causes more harm than benefit. We must not execute exercises too rapidly or increase the tension in the upper or lower abdominal area. Raising the legs while performing abdominal exercises can compromise other muscle groups, such as the psoas and the lumbar region.

You may be interested in activating certain muscles and broadening your range of postures. It is important to follow the instructions of a professional. We must know that the upper region of the rectus abdominis contracts with more force than the lower one. It is necessary, therefore, to prioritize exercise quality over quantity.

The risk of a six-pack

Thoroughly working out the abdominal and pelvic floor muscles is preferable to exercising just the rectus abdominis, which defines a six-pack. Inadequate exercises can lead to urinary incontinence problems, especially in women.

For much of the population, a key goal of strength training is to hypertrophy, or increase muscle mass. Scientific studies show that it is not necessary to perform repetitions until the muscle fails, since muscle hypertrophy can be achieved regardless of the load used in training. However, muscle strength improves with heavier weights. When it comes to repeating until muscle failure, reducing rest between sets, or using moderate to low loads, the studies remain clear: muscle mass can be increased with all methods.

To stretch or not to stretch?

Scientific evidence also clarifies whether or not you should stretch between sets and exercises. Passive, low-intensity stretching does not produce beneficial changes in muscle size and structure, whereas stretching involving tension with loads or muscle activation can lead to increased muscle mass (hypertrophy). A professional trainer can tell you the best way to train according to your needs and time.

Stretching before exercising helps to prevent injuries due to excess muscle tension. Regarding its passive or dynamic use, it will depend on the type of training: active or dynamic stretching is better to prepare the muscles for high intensity efforts, while passive stretching helps to improve flexibility and range of motion. Again, a gym-bro should not bypass common sense and alter the training routine: you always have to stretch, but depending on the effort required in the session.

Strength for children and adults

Some believe that children should not perform strength training, as it will reduce their growth. This is a myth. The American Academy of Pediatrics released a 2008 guide on the benefits of strength training in children and adolescents. The report observes that strength training improves children’s muscle strength and reduces injuries, as long as the exercise is supervised by professionals, in physical education classes and extracurricular activities.

Finally, we must not forget our elders. It is commonly believed that the older someone is, the less strength training they should do. Strength training has multiple benefits for your health: it reduces sarcopenia (muscular weakness) and loss of mobility. Anyone should start with low loads and volume, in order to progress to exercises of moderate to high intensity. It has also been observed that for older octogenarians, multicomponent training, which includes strength work, can improve their physical condition.

It is important to banish the idea of strength training as exclusively associated with gym bros. Strength training is recommended for children, the elderly, pregnant women, the chronically ill and more. The key is to put yourself in the hands of a professional who knows how to guide your routine.

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