Don't resolve to: Run farther and longer.
If you're trying to lose weight and you're already running (or cycling or doing another form of cardio) for 30 minutes a day, tacking extra time on to your workout isn't going to help—and it may even hurt. In an intriguing study by Danish researchers last year, men who worked out daily for 30 minutes lost more weight than those who worked out at the same intensity for an hour (an average of 7 pounds vs. 5 pounds, over 13 weeks
). The researchers concluded that the added exertion may have prompted the 60-minute group to feel hungrier than usual (so they ate more) as well as more drained (so they took the elevator instead of the stairs and spent more time recovering and relaxing
Do resolve to:
Lift weights. Research has shown that adding strength-training to your workouts can help you build muscle and lose weight—in the form of fat, no less