Aerobic exercises are performed for the sole purpose of losing weight. Achieve the goal is possible only if you do aerobics on an empty stomach, especially in the morning-immediately after awakening. By this time, glycogen stores in the muscles are depleted, blood sugar and insulin (a hormone that prevents the breakdown of fatty deposits) are almost non-existent.
If your goal is only to lose weight and you do not care about the size of muscle mass, then there is no problem. However, for a bodybuilder, aerobics (or, as they say, cardio) on an empty stomach carries a risk of significant muscle loss.
The fact is that any physical activity for our body is perceived as a stressful situation in which it begins to actively produce cortisol, adrenaline, glucagon, norepinephrine – all these hormones are necessary to activate energy processes: the consumption of glycogen, fats and… the division of muscle filaments (myofibrils). Fibrils contain amino acids that can be used for conversion to glucose – a chain of chemical reactions characterized by extremely low efficiency: you will lose a lot of muscle and get little energy.
Simultaneously, you can lose weight and maintain the volume of muscle tissue, but this is difficult: the body from the aerobic mode of work goes into anaerobic mode. This happens with a marked increase in the number of heartbeats (up to 65% of the maximum). In other words, for example, jogging should be performed at a speed of no more than 7-9 km / h.secondly, the duration of fasting training for an untrained person should be about 40-45 minutes, and for a trained person-no more than 30. A paradox? Whit, just the body of a trained person rebuilds the metabolism faster: he begins to spend fat earlier, but earlier is taken for muscles.
Thirdly, immediately before training, use amino acids BCAA: it is because of their lack that the body breaks down muscle threads-if they come from outside before exercise, the catabolic effect will decrease significantly. This rule is all the more relevant the larger the initial muscle mass.
Fitness and health 