It sounds like it was an optional pre-season conditioning work out during which weight lifting is a typical activity. Acquire and submit written instructions from her doctors and the coach MUST adhere to them. Every doctor knows more about a kid's health than every coach. After that if the coach is still going to put pressure on your kid to do things she shouldn't then I wouldn't go to the AD or look for the coach in the parking lot, I would simply remove my kid from the team because her long term health is the only issue that should matter. Even if you go to the school administration and are able to successfully cause the coach's removal that is going to take weeks to happen during which time that coach may pressure your kid into an activity that causes her a permanent disability and that can not happen if you remove her from the team.