I am curious what you guys have found to be the ideal fasting length in order to still preserve muscle. I have done a number of 15 day fast and one one month long water fast. In all cases the weight always came back fully. My hypothesis is that for me long-term water fasting results in slower metabolism and muscle catabolism. I am currently halfway into a seven day fast. I am curious if this might be a better length for achieving weight loss while preserving muscle, or if there is a better length.
I’m currently experimenting with working out 3 days a week and fasting the other 4. Calorie wise BMR + 10% on workout days and 0 calories on other days, so far I’m actually gaining strength with this regime so of all the fasting I’ve done, 1-2 day fasts seems best for preserving LBM.
You will lose muscle with extended fasts.
Good news is, you won’t lose much. The body is very good at preserving muscle.
I tend to workout after a refeed. When aiming for weight loss I don’t notice a drop in strength but my fasts only last for 36 hours at most.
Focus on lifting to regain the muscles you lose when you’re not in a fasted state.
Eat lots of protein (and well in general) when not fasting would be the best way to preserve.
I did year ago repeating 3 day fast and 2-3 day eating. I made gainst from deadlift from 160->180kg during that period and shortly after. I think with this style is quite easy to retain muscle. The growth hormon spikes at day 3, so hitting gym and eating that day is value town :D
I wouldn’t be concerned with muscle loss. The studies cited so far show amino acid oxidation. Amino acids build a lot more in our bodies than muscle, and it is folly to suggest that it will be 100% muscle (of the amino acids oxidation) that is being burned after 72 hours. Not only this, muscle composition is like 60% water or some shit.
Here’s what I’d do if i were you, and truly worried about muscle loss (which you shouldn’t be, but what do i know? I’m just a rando on the internet):
Pick a series of exercises that you can do reps to failure with. Target large muscle groups. Push ups, jumping squats, pull ups, dead lifting, you name it. Record yourself doing these exercises to failure, and notate your results. Give it like 2 weeks, and then do a 7-14 day fast. Repeat the exercises. Notate the results. Chances are, your reps are pretty neat identical. Mine sure were.