Do muscles deteriorate over time? If so how fast?

Answer 1

if you havent worked out for 48 hours you already start losing muscle.
with age people lose muscle - after 30 you start losing 4%/decade if you exercise and 10%/decade if you dont exercise.

Answer 2

Well, muscles start to deteriorate by two causes, nonuse , or problems of nerves, Well, how fast, It's hard to say, but I am going to say you that within a month you can see the difference, cellular atrophy, is the cause...
Making excercises, are enough to maintain them healthy

Answer 3

yes with aging they atrophy. same way when you excercise added muscle over time will atrophy if you quit exercising. no it doesn't turn to fat because muscle and fat are physically made up of different tissues. quitting exercising and not adjusting your diet is the cause of fat being put on.