The 10 biggest fitness myths
Here are the 10 biggest fitness myths.
Some of these fitness myths are remarkably persistent. Do you already know them all?
No. 1 of the fitness myths: Many repetitions and little weight for more muscle definition
This myth is probably the most persistent one. First of all: whether your muscle is visible or not depends mainly on the size of your muscle mass and your fat mass. The recipe for "defined muscles" is therefore simply reducing fat mass (losing body fat) while at the same time locally increasing lean mass (building muscle mass). These muscles are more visible the less body fat covers them. You reduce body fat mainly through the right diet (negative energy balance).
No. 2 of the fitness myths: Abdominal training can burn off the fat around the belly.
1000 crunches will tighten your belly and bring out your abs. You hear this again and again. Unfortunately, you cannot control where your fat loss takes place. So you will not lose more fat from your belly just because you do countless crunches. Whether your abs are ultimately visible or not is therefore mainly a question of body fat percentage. Training and the right diet can of course lower this. Unfortunately, not directly at the belly or exactly where you want. Every body manages its stored fat individually. Targeted fat loss is therefore not possible through training.
No. 3 of the fitness myths: If I perform the strength exercise quickly, my muscles become faster.
Contrary to popular belief, "explosive" training makes the muscle fibres slower at the level of their molecular motors (switch from muscle fibre type 2X to 2A). Inactivity (voluntary or forced) makes the muscle fibres "faster" (switch from 2A to 2X).
The "intermuscular coordination", understood as the timing of force production by the muscles involved, largely determines movement speed. Coordination should be trained in the sport itself, because this adaptation is probably not transferable from one movement to another.
It is also assumed that in humans, crossing the boundary between 2 and 1 is unlikely under normal circumstances. Therefore, contrary to popular belief, endurance training on average does not lead to an increase in type 1 fibres either.
No. 4 of the fitness myths: The more protein I consume, the more muscle I can build.
Scientific studies clearly show that just under 10 g of essential amino acids is enough to maximise muscle protein synthesis, but protein breakdown increases with protein portions > 20-25 g per portion. That is why you should make sure to consume "high-dose" protein sources that contain as high a proportion of essential amino acids as possible. It therefore makes little sense to consume protein supplements that maximise protein synthesis per portion but, based on the high total protein amount (for example 40 g per portion), also unnecessarily boost protein breakdown.
You can calculate your protein requirement per portion as follows:
- Man: body weight x 0.25g
- Woman: body weight x 0.23g
No. 5 of the fitness myths: With heavy weights I can build more muscle.
Unfortunately, we have to disappoint you. The training weight is not the most important factor in your training. The resistance should be chosen so that you cannot move it even a millimetre at the earliest after 60 seconds and at the latest after 120 seconds. Now let us assume you do your strength training with about 90% of your maximum possible resistance. You can then move the resistance until your strength falls below these 90%. But you still have almost 90% of your possible strength left. You simply cannot move the resistance any more, because it is too heavy. In this case you would have to do countless sets of the same exercise to fatigue the muscle. This costs you unnecessary time and additionally strains the central nervous system.
Now let us assume you choose a resistance for your strength training that is about 60% of your possible resistance. You can then move the resistance until your muscle strength for the exercise task is less than these 60%. Your muscle will therefore definitely be more exhausted.
So choose a resistance that you can move correctly and slowly for about 60 to about 120 seconds.
No. 6 of the fitness myths: Fat burning only starts after 20 minutes.
It is really astonishing how stubbornly this misconception persists. Whether it concerns nerve cells that transmit electrical impulses or muscle cells that perform mechanical work, every cell in the human body needs energy. This energy is stored within the cells in the form of adenosine triphosphate (ATP) and is released when ATP is split into adenosine diphosphate (ADP) and free phosphate (Pi). Since only a very limited supply of ATP is stored in the muscles, replenishment must constantly be provided by regenerating ATP from ADP and Pi. This regeneration takes place through 3 different systems, whose characteristics are matched to the properties of the muscle fibres.
The systems are:
- the phosphagen system (highest metabolic power but lowest capacity)
- the glycolytic system (lower metabolic power but higher capacity than the phosphagen system)
- mitochondrial respiration (lowest metabolic power, but by far the greatest capacity)
The 3 systems always run at the same time, so your fat burning is always running! The proportional composition of these 3 systems differs depending on the intensity and duration of physical exertion.
No. 7 of the fitness myths: Stretching after strength training is important.
In general, muscles (or muscle fibres) can follow 3 strategies to adapt to changed functional demands: increase or decrease in length, increase or decrease in physiological cross-section, and contractile and metabolic reprogramming. Myofibrils can become longer actively or passively. Actively means that the lengthening occurs with simultaneous contraction (the muscle is activated and produces force). Muscle contraction while the muscle length is increasing is called "eccentric" contraction. Passively means that the change in length occurs without contraction (for example through contraction of the antagonists).
In contrast to lengthening, myofibrils can only be shortened actively ("concentric contraction"). It has long been known that muscles can adapt to a new functional length by adding or removing sarcomeres in series at the ends of myofibrils. Contractions that are not performed over the full range of motion (at short muscle length) lead to a decrease in the number of sarcomeres in series. Contractions at long muscle length lead to an increase in the number of sarcomeres in series, provided the exercise is performed over the everyday range of movement. This adaptation has so far not been demonstrated with passive lengthening. The muscle should therefore be trained through its full possible range of motion.
No. 8 of the fitness myths: Women respond to strength training worse than men.
Scientific studies clearly show that women gain about as much muscle mass and strength as men through several months of strength training. Hubal et al. conducted a study in 2005 in which they had 585 participants (243 women, 342 men) aged 18-40 train their non-dominant arm for 12 weeks. Among other things, the cross-sectional area of the upper arm muscle was measured.
After 12 weeks of strength training, the results were as follows:
- On average, the men increased their muscle cross-section by 20%, the women by 18%.
No. 9 of the fitness myths: You have to warm up before strength training.
"Warming up" in the sense of a non-specific rise in muscle temperature before strength training brings no additional benefit. The risk of muscular injuries depends less on the temperature state of the relevant muscles than on the "explosiveness" of the movement. Since movements in strength training are performed slowly, warming up is not necessarily required.
No. 10 of the fitness myths: Stretching can prevent muscle soreness.
Muscle soreness is a micro-injury to the muscle. The Z-disc of the sarcomere therefore has a tear. You certainly cannot prevent muscle soreness by stretching.
Facts about muscle soreness (delayed-onset muscle soreness):
- Results from eccentric muscle contractions and/or contractions at long muscle length
- Goes hand in hand with microlesions in the muscle
- Goes hand in hand with oedema (fluid accumulation in the tissue) and an inflammatory reaction
- Can be felt or measured a few hours to weeks after intense exertion
So lactate has nothing to do with muscle soreness either.
