Just wondering if its possible to build muscle on a prolonged fast. I know about weight loss and calories in calories out really well. But building muscle is not as clear to me. Do you have to have the intake of protein to build muscle? Or is it more about the tearing and recovery of lifting that does it? During a fast, do you lose muscle mass even if you are still working out or is it purely fat/water loss? Thanks!
Sooo, according to Dr Fung, you don’t lose muscle because when you do an extended fast your body releases HGH and other hormones to protect your muscle from wasting away.
There will be some breakdown (as there normally is) but when you refeed, your body takes those nutrients and rebuilds right away. So it’s important to eat well on refeed.
But to build? Prly not.
Fun fact, every day our bodies rebuild about 500 g of protein. About 400 recycling our own, about 100g from what we eat (very generic numbers, everyone’s different).
When you do a prolonged fast, your body ramps up autophagy (the recycling). If you’re like the typical obese person, you’ll have up to 20 pounds of extra protein the body can use for rebuilding (in the form or extra skin, connective tissue, and blood vessels). Info also from Dr Fung.
A prolonged fast is going to see a slight bit of muscle loss, but it will be mostly fat and water. You will not be able to build muscle on a prolonged fast, but working out might minimize the muscle lost (which shouldn’t be that much in the first place).