Improve Your Sweatitude: 9 Motivation Rut Busters

"I hate cardio."

Rut Buster: Swap endless treadmill time for circuits, suggests trainer Jim Karas, author of The 7-Day Energy Surge. According to a study in the British Journal of Sports Medicine, circuit training beats aerobic exercise for building upper-body strength while giving an equal boost in cardio capacity. Try Karas's technique: Alternate one-minute sets of upper- and lower-body moves, resting for 30 seconds in between and doing each set with enough weight so that your muscles cry uncle at 10 reps.