Does Strength Training Build Stronger Bones? What NIH Says

Yes, resistance training puts stress on bones, and the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), part of the National Institutes of Health, says that can make them stronger. NIAMS recommends combining it with weight-bearing and balance exercise. The federal Physical Activity Guidelines for Americans describe the same overload principle.

1. Why bones need attention

NIAMS describes two changes that come with age:

• Osteoporosis risk rises. Osteoporosis is a disease that makes bones weak and brittle, which increases the risk of fractures.
• Muscle tends to decline. NIAMS notes that older adults tend to lose muscle, a condition called sarcopenia, and that strong muscles help with balance and reduce the risk of falling and breaking bones.

So bone health is not only about bones. Muscle strength and balance are part of the same picture.

2. What exercise does for bones

NIAMS lists the benefits of exercise for bone in adults and children of any age. Exercise:

• builds strong bones in children
• strengthens both muscles and bones in children and adults
• prevents bone loss in adults
• makes bone denser and replaces old bone with new bone
• improves balance and coordination
• helps prevent falls and fractures
• helps prevent osteoporosis

3. How resistance training helps

NIAMS describes resistance training, or weight lifting, as exercise that adds resistance to movement to make muscles work harder and become stronger. The key line for bones: these exercises put stress on bones, so they can make bones stronger as well.

The Physical Activity Guidelines describe the same principle from the other direction. They explain that muscle-strengthening and bone-strengthening activities overload muscles and bones, and that this overload makes them stronger. Bones, like muscles, adapt to the demands placed on them.

NIAMS lists the forms resistance training can take:

• weight machines
• free weights
• resistance bands
• your own body weight, such as push-ups or pull-ups

4. The best approach is a combination

NIAMS does not recommend strength training on its own. It says a combination of three types of exercise is best for building and maintaining healthy bones and preventing falls and fractures:

Notice that lunges appear in the balance list. Some strength moves do double duty, which makes a short routine more efficient.

5. A combined week for a beginner

Here is one way to put the three types into a week, using only NIAMS's examples. The structure is illustrative, not a prescription:

• Strength days: a short session with push-ups and lunges, or weights, bands, or machines.
• Most days: brisk walking, aiming for the 3 to 4 mph pace NIAMS describes.
• A few minutes each strength day: balance work, such as walking backwards or shifting your weight while standing on one foot.

The brisk walking pace is easy to check with simple math: at 3 mph a mile takes 20 minutes, and at 4 mph it takes 15 minutes. If a mile takes much longer than 20 minutes, you are probably below the brisk range NIAMS gives.

6. Children and teens

NIAMS also covers younger people. It says children and teens aged 6 to 17 should be active at least 1 hour every day, mostly at moderate or vigorous intensity, and use some of that time for muscle-strengthening exercise at least 3 days a week and bone-strengthening exercise at least 3 days a week. The Physical Activity Guidelines give the same structure for this age group.

7. When to check with a provider first

NIAMS is specific about who should talk to a health care provider before starting: anyone with low bone density (sometimes called osteopenia), osteoporosis, or other physical limitations. NIAMS says a provider can help you choose types of physical activity that are safe for you and good for your bone health.

8. Key takeaways

• NIAMS says resistance training puts stress on bones and can make them stronger, not just muscles.
• The best approach for bones combines weight-bearing exercise, resistance training, and balance training.
• Brisk walking for bone health means about 3 to 4 miles per hour, or 15 to 20 minutes per mile.
• Children and teens need muscle- and bone-strengthening exercise at least 3 days a week each.
• People with low bone density or osteoporosis should talk to a provider before starting.

This article is general information, not medical advice. Talk with a doctor or physical therapist before starting a new exercise routine, especially if you have a health condition or injury.