When losing 100+ lbs, how much muscle is lost?

EDollah

The subject heading pretty much says it all.

Actually I'll narrow the scope of the question a bit.

How much muscle would I expect to lose going from 340 to 220 (120 pounds for math challenged) if I'm doing the things I'm supposed to do to lose mostly fat. That is, lifting weights for strength, consuming enough protein and not overdoing cardio. Basically, a "best case" scenario for maintaining muscle.

Just out of curiosity, what's the answer for someone that's not lifting weights and just sprinting to the finish line to lose as much weight as possible without regard to body composition?

MCLA4mom

I lost a little less than you plan to (75lbs). I ate enough protein to protect my muscle. That was key for me.
I honestly didn't lose any muscle. I did a little strength training and some running. I didn't go crazy with the exercise. I think I even gained some muscle (or maybe it was just more visible from taking off layers of fat).

nwg74

Weight loss will always been split between fat and muscle loss. Strength training will minimise the muscle loss but there will still be some.

I have lost 200 pounds with no strength training (medical reasons) and I think I look quite good. Sure, I have lost noticeable muscle in my arms and around my core. I still have a hanging stomach/excess skin though. I believe that would look better if I had more muscle underneath / in my arms.

Keep what you are doing and it will work out for the best.

caribear1984

I'm not really sure if there's any way to predict that. You will inevitably lose LBM, which includes muscle but also things like connective tissue and blood vessels (less fat to feed, fewer/smaller vessels needed). It would be extremely difficult to predict how much of that would be muscle. It sounds like you are doing a great job minimizing that loss though. Keep up the good work!