A couple days of resistance training per week can lead to big changes in your body. It'll strengthen your muscles and bones, give your posture a lift, and boost your mood. Strength training also stokes your metabolism, so you'll burn more calories even when you rest. And it slashes your odds of getting injured.
Follow these dos and don'ts to get the best results.
Target every zone. Aim for 2 to 3 days of strength training per week. Be sure to work every muscle group, including your chest, back, shoulders, legs, arms, abs, hips, and low back, says Michael A. Clark, DPT, founder of the National Academy of Sports Medicine. Overlooking a body part can lead to muscle imbalances and posture problems.
Start light. If you're a beginner, stick with light weights for the first 3 to 4 weeks. You may feel stronger after a few workouts, but just because you can lift heavier weights doesn't mean you should, Clark says. Your body needs time to build enough strength to fend off injuries.
Focus on form. Follow Clark's tips: Keep your feet straight -- imagine yourself on skis. Align your knees with your toes. Work your abs -- tighten your stomach muscles and pull your belly button in. Keep your shoulders back and down (avoid shrugging). And align your ears with your shoulders.
Add weight but use keep using good form. Start with one set of eight to 12 repetitions. Try to build up to three sets of 12 to 15 reps. Add more gradually. A good rule of thumb: When you can do 12 reps using good form, ratchet up the weight.
Take time off. "Strength training causes tiny tears in your muscle tissue," Clark says. "When you rest, your muscles recover from the micro-trauma. It's this tearing and repairing process that allows your muscles to get stronger." Give yourself 48 hours between sessions and get plenty of sleep.
Don't hold your breath. Keep breathing as you lift and lower your weight. Try to exhale as you lift the weight and inhale as you lower it.
Don't go fast. Slow, controlled movements are better. Whether it's a dumbbell, band, or machine, lift for a count of two, lower for three or four.
Don't quit too soon. You don't have to stop when you reach the end of a set. You can try "repping out" or "going to failure." This means lifting until you can't do any more reps with good form. It's tough, but it's an ace at building strength in less time.
Don't fall into a rut. "It's easy to get comfortable and fall into the habit of doing the same exercises and movements," Clark says.
But mixing things up challenges different body parts and keeps boredom at bay. Vary the equipment -- try dumbbells, resistance bands, cables, stability balls, or exercises that use your body weight. Change up your intensity -- switch between tough and easy days. And alternate your grip, meaning change from palms down to palms up, or vice versa.
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