I'm always looking for new ways to make exercise challenging—and that's exactly what I found when I recently tried a "super-slow" strength-training routine. To do it yourself: Choose a heavy weight (I used 8-pound barbells instead of my usual 5-pounders). Then do your regular moves—biceps curls, shoulder presses, etc.—taking 10 seconds to lift it and 10 seconds to lower it. You should only be able to do 6 to 8 reps. By the time you've completed your eighth repetition, your muscles should be too fatigued to do another. I've been lifting weights for nearly a year now, but I was still shocked at how hard and tiring it was—after half an hour my whole body was shaking. I've only done the routine three times, and I'm already seeing new definition in my arms. So while the workout might be slow, the benefits come fast!