Weight Lifting and Strength Training Tips for Teens

Medically Reviewed by Renee A. Alli, MD on March 19, 2024
5 min read

"I want to lift weights to be stronger," says "Ella" (not her real name), 17. "But I don't want to look like a football player!"

"Hey, I do want to look like a football player," says "Josh," 14. "I'm going out for the team next year and need to bulk up."

There are good reasons, although they are different for Ella and Josh, why both teens should do strength training: it builds muscle strength, tones the body, builds endurance, develops stronger bones, promotes weight loss , and improves brain and mental health. But they need to do strength training properly to avoid injury. Here are some questions, answers, and tips about strength training:

Q.What Is Strength Training?

A. Strength training is a program of exercises that increases muscle strength and endurance. Strength training is not necessarily the same thing as power lifting or even weight lifting . While power lifters use heavy weights to build large muscles, people who strength train may use lighter weights or resistance and multiple repetitions. You can do strength training with weight machines or free weights. But you can also do it with resistance bands, ankle or wrist weights, or using your own body weight as you would with a pushup.

Q. Is Strength Training Dangerous?

A. Strength training is not dangerous if you do it with proper supervision and instruction. It's a safe and effective way to strengthen muscles (including the heart), look more toned, and help control weight. It also helps strengthen bones. But because teens are still developing, it's important to get an OK from your doctor and to seek professional instruction to make sure you do it correctly.

Q. Do Girls Get Big Muscles With Strength Training?

A. It would be tough for a girl to get big muscles with strength training -- unless they do a lot of it. Girls produce less testosterone (male hormone) than guys, so their muscle size builds less rapidly. Guys who've started puberty will be able to build bigger muscles lifting weights.

Q. Is Strength Training Aerobic?

A. Endurance exercise like walking, swimming, or biking is aerobic, as your muscles use oxygen more efficiently to strengthen your heart and lungs. Aerobic activity increases your heart rate and keeps it up for an extended period of time. Strength training is usually anaerobic (meaning "without oxygen"), as your muscles work against the weight.

Q. What if I Don't Have a Gym Membership?

A. You don't have to go to a gym to do strength training. Teens can use resistance bands from a sporting goods store, free weights, and do water-resistance exercises. You can even use cans of vegetables or fruits from your kitchen pantry as free weights!

Q. Should I Use Heavy Weights?

A. Don't use heavy weights yet! Teens should start out with lighter weights, proper form, and more repetitions. A good rule of thumb is to start with a weight you can easily lift 10 times, with the last two repetitions being increasingly difficult. For some teens, this might be 1 pound to 2 pounds. If you are strong and fit, you might start at 15 pounds to 20 pounds. When lifting, move the weights in a smooth, steady motion. Avoid jerky movements and sudden drops.

As your muscles gain strength, and if there is no pain, slowly increase the weight in 1- to 2.5 -pound increments if using free weights, in 5-pound increments if using gym machines. Stay away from very heavy weights until you are fully through puberty and growth, as it could damage tendons and bones. Make sure you warm up and incorporate stretching as part of your weight training. Talk to your doctor or PE coach about the type of weights that are best for you.

Q. Is "No Pain, No Gain" True?

A. No pain, no gain is a myth. If it hurts, you're using too much weight or resistance. If your muscles are very sore, do not do strength training until you are relatively pain-free.

Q. Will I Get Bulky and Inflexible?

A. To look toned and lean, it's important to do other exercises along with strength training, including stretching and endurance exercise (like walking, swimming, stepping).

Q. Will Strength Training Give Me Flat Abs?

A. You can't "spot-reduce" abs or any other body part with exercise. You need to exercise the total body for maximum results. However, properly done abdominal "crunches" will improve abdominal muscle tone. Again, you need to be trained in how to do these correctly for best results without injury.

Q. Do I Have to Breathe a Certain Way During Strength Training?

A. Always remember to exhale during exertion (pulling up a weight), and inhale on the downswing. Many people forget about doing this. But if you intentionally practice the breathing, you'll remember.

Q. What Can I Expect From Strength Training?

A. You'll feel stronger with strength training, and find it easier to be physically active. You'll have more energy and you'll probably lose weight, depending on how regularly you work out. Some findings estimate that for each pound of muscle you add to your body, you burn an additional 35 calories to 50 calories per day. So, an extra 5 pounds of muscle will burn approximately 175 calories-250 calories a day. That's an extra pound of fat every 14-20 days. Guys will look toned and see a difference in muscle size; girls will look fit and toned. Sometimes your actual weight may stay the same but your body will feel firmer with more defined muscles.

For teens wanting to start strength training, here are some tips for getting started:

Warm Up and Stretch. Always warm up before starting your workout routine. A warm-up like walking in place or riding a stationary bike for 5-10 minutes boosts circulation and prepares muscles and joints for activity. After you warm up, do some stretching to increase flexibility. Hold each stretch for 10-30 seconds. Don't overstretch or bounce during the stretch, to avoid straining your muscles and joints.

As you plan your strengthening program, start two to three times per week for about 20 minutes. Allow at least 24 hours between sessions for your muscles to recover. And remember to also stay hydrated and eat a healthy diet.

It takes several weeks to see results with a strengthening program, so once you make the commitment, stick with it. Over time, you'll notice a difference in your strength and appearance.