SAILOR64: not to contradict you, but actually, science has found that lactic acid is not held in the muscle for days. The pain we get from workouts is called DOMS, and it's caused by microscopic tears in the muscle fibers, not lactic acid buildup as we used to believe. :) It does cause "the burn" we love so much, but it is cleared out very soon after we exercise.
To the OP: Stop doing situps. :) Seriously, they're not very efficient exercises, and these days, it's much better to do exercises like planks or even crunches. Situps can put unnecessary strain on your back, and aren't more effective than other exercises, anyway.
You'll find you recover more quickly next time. As your body rests, and repairs those microscopic tears... t hat's how it gets stronger! You hurt not because you're "weak" or "out of shape", you just haven't done that kind of movement in a long time and your muscles aren't used to it.
Edited by: DRAGONCHILDE at: 1/29/2013 (11:59)
Writer, mother, wife, and breadwinner. I love to run, but running doesn't love me, so I'm switching to my low-impact bike.
I'm not pregnant, just fat: My blog. fatnotpregnant.blogspot.com/
| current weight: 190.6