You say you take fitness seriously. But until you find yourself running obstacle courses to the Rocky theme at 6 in the morning, panting your way through conversations about fantasy football leagues, you don’t know what serious is. Welcome to Bay Area Boot Camp. The four-week program (for women only — sorry, guys) meets five days a week at Crissy Field’s East Beach at 5:30 a.m., 6:30 a.m., or 9 a.m. (slackers) and is led by hard-core fitness enthusiasts. But don’t translate “hard-core” as “no fun.” Activities include jumping rope, obstacle courses, running, power drills, and stair climbing, which make the experience a little reminiscent of P.E. class. (Okay, maybe a little harder.) But suffice it to say, your ass will be in mighty fine shape after four weeks of training. Pre- and post-evaluations of your body fat count, timed mile, and strength tests will be the proof in the pudding. (Not to mention your killer new abs). Just don’t join their fantasy football league. That would be taking things to the extreme. Bay Area Boot Camp (415-567-7411 or bayareabootcamp.com).