Does your doctor lift, or is he the typical doctor who smokes, is fat and believes squats are bad for the knees?
I recommend working the abs with weight (no more than 10 reps per set - abs are no different than any other muscle, so train them the same way) to strengthen them. When lifting heavy weight, hold your breath in and push the abs out.
Firearms instructor/Glock armorer
Airplane pilot - Commercial/Instrument rating