Had to quit the elliptical because my natural gait didn't match it and I was getting pain in my right knee and numb toes as a result. Switched to an arc trainer and no more knee pain. Did 30 min arc plus 15 min circuit training earlier today, plus 150 crunches (50 straight, 50 each side cross ways) and 50 leg lifts plus 2 minutes plank. Gonna be sore tomorrow.