Hi so is it normal when you like suck your stomach in for your one side of your rib cage to pop out? Cuz mine has been like this for a while and I’m confused?!?

If you were running a marathon, which type of muscle fibers would be most useful to you? a. slow-twitch b. fast-twitch, type i a c. intermediate-twitch, type ii b d. slow-intermediate twitch, type i b select the best answer from the choices provided. a b c d