It's nearly always a side effect of weight loss, and it's a
good thing. It's confusing how people act like it's bad.
If you're obese, your legs are enormously strong with crazy amounts of muscle. Have you ever seen someone obese do leg presses at the gym? They can handle tons of weight.
When you lose weight, you don't need all that extra muscle. If you're carrying around 180 lbs instead of 300 lbs on your frame, all that extra muscle goes away because there's no point in keeping it. This is a good thing.
Even if you go from 200 lbs to 180 lbs, there's a level of muscle you don't need anymore.
Losing muscle as you lose weight is natural and good. Now, obviously you don't want to lose so much that you become weak for your size, but that won't happen if you continue to be physically active. Your body is exceptionally good at maintaining the exact right level of muscle to meet the regular stresses it undergoes. (Provided you are eating enough protein, but that's easy.)
If you're obese, your legs are enormously strong with crazy amounts of muscle. Have you ever seen someone obese do leg presses at the gym? They can handle tons of weight.
When you lose weight, you don't need all that extra muscle. If you're carrying around 180 lbs instead of 300 lbs on your frame, all that extra muscle goes away because there's no point in keeping it. This is a good thing.
Even if you go from 200 lbs to 180 lbs, there's a level of muscle you don't need anymore.
Losing muscle as you lose weight is natural and good. Now, obviously you don't want to lose so much that you become weak for your size, but that won't happen if you continue to be physically active. Your body is exceptionally good at maintaining the exact right level of muscle to meet the regular stresses it undergoes. (Provided you are eating enough protein, but that's easy.)