Myth: If you don’t work out for several months, your muscle will turn to fat.
Reality: The short answer: the first half of that sentence is true and that last half is false.
If you stop strength training for a few months, muscle atrophies when it is not being used. This means that without tension exercise that breaks down and rebuilds the muscle, your muscles shrink, and you burn fewer calories because muscle burns calories more effectively than other body tissue. Therefore, if you have less muscle mass, you can gain fat easier.
The rate muscle degenerates depends on age and body type, but as a rule of thumb, it begins to deteriorate after about two weeks of inactivity. So if you take a break from muscle-strengthening work for two weeks only, and then return, you can begin back where you left off without declines in strength and muscle size.
However, fat cells and muscle cells are anatomically different. Fat is often the layer on top of (or perhaps in between) the muscle fibres. One does not “turn into” the other; one declines without use as the other may increase due to lack of exercise/eating habits.
Juergen Reinhardt, CPT-BCRPA, B.PT, CMT, is a German trained physiotherapist, personal trainer and sports instructor specializing in rehabilitation training following illness or injury. He has worked at Body & Soul in Vancouver for 10 years.
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