And resistance exercise helps keep you injury-free, so you're not stuck on the couch when you could be incinerating calories on a run. A recent study in the journal Clinical Biomechanics found that female runners who did six weeks of lower-body exercises, like the ones that follow, improved their leg strength, particularly in the hips—a common source of pain and injury for runners.
If your schedule allows it, try lifting before you run to increase fat burning while you run. "Resistance training is mostly a carb-burning activity," explains Westcott. "After about 20 minutes of strength training, you deplete your glycogen stores (carbs) so fat is readily available to burn."
And even if you don't follow strength training with a run, you still get an after burn.
"You elevate your metabolism by 25 percent for the 60 minutes following resistance exercise," says Westcott. So if you burn 200 calories in a 20-minute strength session, count on sizzling an additional 50 calories after your last rep. This total-body strength workout designed by Kate Moran, a trainer at Equinox gym in Chicago, takes no more than 20 minutes and complements the running plans above. "Working the glutes, hamstrings, and core will help you prevent injury and become stronger so that you get more out of your runs," says Moran.
Do three sets of 12 to 15 reps (unless otherwise noted) twice a week; rest for 30 seconds between sets. All you'll need to complete the routine is a pair of five- to 10-pound dumbbells and a resistance band.
Unilateral lift Grab a dumbbell in each hand, stand on one leg (keep it as straight as possible), and lift the other leg slightly off the floor. With your raised foot stationary, lean forward with your arms straight and extended toward the floor as you bend at the hips (not the knees) and keep your back flat. Return to start without lowering your raised foot.
Lateral-band walk: Place a resistance band around your ankles. Stand with your feet hip-width apart, then step to the side with one foot, keeping your toes facing forward. Bring your feet back together; repeat. Walk 15 steps in one direction, and then 15 steps back, leading with the opposite foot. That's one set. Repeat three times.
Marching hip raise: Lie on your back with your knees bent and feet flat on the floor. Raise your hips to create a straight line from your knees to your shoulders. Lift one knee to your chest, trying not to drop your hips. Lower, then lift your other knee to your chest. That's one rep.
Leg raise: Lie on your back with your arms by your sides, palms up. Keeping your legs straight, raise them until they are perpendicular to the floor. Slowly bring them back to the starting position, keeping your lower back against the floor.
Go Long (in Moderation)
The good news is that you don't need to log more than one long run a week to get the max calorie-burning benefit, and a long run means 30 minutes or more. This sustained effort will improve your endurance by increasing your heart's capacity and strengthening ligaments and tendons, so you feel stronger during your short runs, says Kastor, who created the "Run Off the Weight" training plans, above. "And the more effort you can put into each workout, the more calories you'll burn."
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