Losing muscle mass and losing muscles are the same thing?
Before we start to investigate the affect of inactivity to the muscles some questions must be answered… The difference between the true muscle loss and muscle mass loss is the main idea of this article…
After any activity the body immediately replaces the energy used during the exercise. The intensity of the exercise that occuring micro tears in muscles starts the adaptation period to have them better service before the next activity. Thus the body rebuild the muscles. It takes 3 to 7 days generally to recover.
Muscle loss and decrease in muscle size are not exactly same things. However muscle is around 75 percent water. Maybe sometimes 80…
There are 2 types of muscle fibers. Type I fiber is oxidative and type II fiber is glycolytic. When the intensity of the activity loads more than %20 of the one rep max that is where type II fibers works. Type II fibers can’t get oxygen instantly because of the blood cut off. Thus after work outs while recovering type II fibers get large.
Depending on several factors like your fitness condition before the inactivity period, your age, sex, nutrition muscle loss time can change… The more muscle mass you have, the more you lose with inactivity.
Commonly people know that carbonhydrates as the body’s primary source of energy. And the second fat, the last prefered source is protein.
At very beginning (in a few days) you lose cardio and at the end (after 3-4 weeks) you lose strength. However, your body tends not to prefer burning muscle over other sources. But without a calorie deficit not using muscles and not doing any work out muscle loss is unavoidable.
Endurance decreases up to 25 percent after a 3-4 week inactivity of cardio according to a study in 2012. Increased red blood cells scales back and capillary density fades.
A decrease about 10-20 percent of muscle mass can occur in ten days of inactivity. But this is not be taken seriously… The decrease of this muscle mass is not accepted to be a true muscle loss. The first biggest decrease is commonly caused by water loss and glycogen depletion in muscles. It can regain quickly after resuming work outs.
True muscle loss occurs after about 3-4 weeks of inactivity or immobility.
When you restart training, muscles respond are far more higher than a beginner because of the remembered muscle growth by genes in that muscles.
Losing your progress is unwilling and you can check if you’re loosing muscle through ‘body composition testing’ or other indicators such as body weight, size and strength level.
Also some medical conditions like malnutrition, diseases (muscular dystrophy, multiple sclerosis, amyothrophic lateral sclerosis, spinal muscular atrophy) and aging can cause muscle wasting. Especially after the age of 55 a typically 1-2% muscle loss a year is unavoidable.
At the end of the day, muscle loss, muscle wasting or muscle atrophy call it whatever you want is usually caused by not exercising regularly your muscles.