Scientists Reveal a Powerful Link Between Physical Activity and Bone Strength

• Moving more and sitting less helps increase bone density (and lower body fat percentage), according to one study.
• Experts explain that exercise stimulates the formation of new bone cells that keep bones from becoming brittle.
• Doctors offer their top exercise and diet tips to keep bones strong as you age.

Bone strength is a real concern for many of us as we get older, but especially for women, who begin to lose bone density at a more rapid rate after menopause. Fortunately, for anyone concerned about their risk of developing osteoporosis (also known as brittle bones) as they age, there’s hope. Researchers have found a powerful link between physical activity and bone density that can help you preserve the bone you have – or even build new bone, if you’re choosing the right forms of exercise.

The study, published in the journal Scientific Reports, analysed data from 9,787 US adults aged 20 to 59 who took part in the National Health and Nutrition Examination Survey between 2011 and 2018. The researchers looked at factors like bone mineral density and body fat percentage, along with how often people were sedentary and how often they were active.

The researchers found that people who had more sedentary lives were less likely to have good bone density in their lower back and more likely to have a higher body fat percentage. But those who were more active were more likely to have better bone density and a lower body fat percentage.

“Our results show that physical activity is a key component of maintaining bone health in both men and women, and is strongly associated with lower body fat percentages,” the researchers wrote. “Healthcare policy makers should consider reducing sedentary activity and increasing physical activity when preventing osteoporosis and obesity.”

So why might working out regularly promote good bone density? In this particular study, the researchers didn’t explore why exercise may help with bone density – they just found a link. However, researchers and doctors do have an idea.

“This study confirms what we know about exercise and bone density,” says Dr Alfred Tallia, a professor of general practice and community health. “Thinning of bone density is called osteoporosis, and is responsible for fractures of the hip and spine whose consequences can take years off a person’s life expectancy. We normally lose bone density as we age.”

The way exercise helps with bone density is slightly complicated but, on a basic level, the physical stress your bones experience when you exercise stimulates them to remodel with extra deposits of calcium and bone-forming cells. This ends up creating stronger and denser bones. Your body reabsorbs old bone and creates new bone throughout your life and, as long as your body keeps a good balance of old and new bone, your bones stay healthy and strong, healthdirect explains.

“Bone density describes the quality of your bone,” says Dr Omar Atassi, an orthopaedic surgeon. “When we’re in our 20s, most of us have normal bone density. As we naturally age, bone gradually loses its strength and becomes more porous.” Dr Atassi compares healthy bones to a solid timber stud. “As we age, our bone can gradually become very porous and weak, like plasterboard,” he says. “Just like when you’re hanging up a heavy picture, you strive to put a nail in the stud instead of the plasterboard, because the plasterboard will have trouble holding up a heavy picture.” If your bone density becomes critically low, your bones will have trouble holding up against the occasional fall or bump, he says. “When we were studs, a simple fall would result in a bruised ego, but when we’re plasterboard, our bones can break,” he adds.

Since this study was published in 2023, others have come out supporting the benefits of exercise for increasing bone density. In a large review and meta-analysis published in Scientific Reports in 2025, both aerobic exercise and resistance training were found to significantly improve bone density in postmenopausal women.

How to improve your bone density

All exercise is good for your overall health, but certain types are considered better for lowering your risk of poor bone density and osteoporosis. “One of the best ways to maintain bone health and prevent osteoporosis is engaging in weight-bearing exercises,” says Dr William Buxton, a neurologist specialising in fall prevention.

Dr Tallia emphasises that activities like walking, gardening, climbing stairs and dancing, which put some stress on your bones, “help prevent falls and help keep bone density loss to a minimum.”

Getting plenty of calcium and vitamin D, through supplements or from the best foods to eat for strong bones, can also help promote good bone health, according to healthdirect. Exercise “combined with a nutritional diet with adequate amounts of calcium – dairy and green leafy vegetables like spinach – and vitamin D, keeps the risk of fracture at bay,” Dr Tallia says. There are also a few habits that aren’t great for your bones. “Drinking [alcohol] increases the risk of osteoporosis,” says Dr Buxton. (Worth noting: Smoking does, too.)

If you’re concerned about your bone density, or if you have a family history of osteoporosis, talk to your GP. They may recommend a bone density scan known as a dual-energy X-ray absorptiometry (DXA), which scans your bones to see where things stand. From there, they can offer personalised recommendations to help with your bone density, which may include a combination of medication and lifestyle changes like increasing exercise.