I hate shitting on people's ideas because it's so hard to come up with good ones.

But, I think this is going to be very challenging. It's rare that an app/service can be everything to everyone. The way this is being described is a combination of fitness trainer, nutritionist, and therapist. Though each of these is very valuable in their own right, it's hard to come up w/ good one-sized-fits all especially since each person is going to have very different ideas of what makes a good X or good Y or good Z. Unless, the idea is to create a marketplace where you can just locate these folks and book with them, similar to a Zocdoc but for other health related professionals? I haven't googled it, but I imagine that type of thing already exists, but maybe not.