If you have been told your bone density is low, or you are looking to protect your bones through menopause or your 50s and 60s, the question is the same. What kind of exercise actually builds bone? The short answer surprises most people. Walking, swimming, and yoga are good for you, but they are not what builds bone density. This guide explains what does.
Why bone density matters after 50
More than 1 million Australians have osteoporosis, and millions more have low bone density (osteopenia) (Healthy Bones Australia). More than 183,000 broken bones happen each year in Australians aged 50 and over because of poor bone health. A minimal-trauma fracture is a broken bone from a fall from standing height or less. The hip, wrist, and spine are the most common sites.
Bone density peaks in your late 20s and stays relatively stable through your 30s and 40s. The drop accelerates after menopause. On average, women lose up to 10 per cent of their bone density in the first five years after menopause as oestrogen levels fall (Better Health Channel). Men lose bone too, just more slowly and a decade later.
The stakes are not abstract. A hip fracture in someone over 65 carries a high risk of hospitalisation and loss of independence. The point of exercise for bone density is not vanity. It is about staying strong, steady, and independent as you get older.
02 · How bone responds
What “osteogenic” means and how bone responds to load
Osteogenic means “bone-forming”. An osteogenic exercise is one that loads the skeleton strongly enough, and rapidly enough, to trigger bone tissue to grow stronger.
Bone is living tissue. It adapts to the loads placed on it. The cells that lay down new bone (osteoblasts) need a clear mechanical signal to do their job. That signal has two ingredients. Magnitude: the size of the force going through the bone. Rate: how fast the force is applied. A heavy load applied quickly is the strongest signal. A light load applied slowly is the weakest. The Exercise and Sports Science Australia position statement sums up the evidence: bone responds positively to impact activities and to high-intensity progressive resistance training (Beck et al, ESSA 2017).
This is why a 20-minute walk does not build bone density much. The force per step is small, and it is applied slowly. The skeleton has already adapted to walking around. To make the bones get stronger, you have to give them a load they are not used to.
Effective bone-loading programs share three features:
- Frequency. At least 3 sessions per week, and most days is better. The 2024 RACGP and Healthy Bones Australia guideline recommends weight-bearing impact exercise on most days, with at least 50 moderate impacts per session, plus resistance training at least twice a week (RACGP and Healthy Bones Australia osteoporosis guideline).
- Progressive overload. The load increases over time as the bone and muscle adapt. A program that stays the same for 12 months does not keep building.
- Specificity. Bone adapts at the site of the load. Loading the spine and hip protects the spine and hip. Loading the wrist protects the wrist.
To make the bones get stronger, you have to give them a load they are not used to.
03 · The osteogenic tiers
How exercise for bone density works: what builds bone and what does not
Not all exercise is equal for bone density. Researchers who study bone rank movements by how strong an osteogenic signal they send. The two clear winners, per the Exercise and Sports Science Australia position statement, are impact activities and high-intensity progressive resistance training (ESSA 2017). The flip side, well established across the bone-exercise research, is that gentle steady aerobic exercise like swimming, cycling, and easy walking does not load the skeleton hard enough to build bone.
Ranked from the strongest bone-building effect to the weakest:
Strongly osteogenic. Two routes sit at the top. High-impact loading (jumping, skipping, box jumps, hopping, gymnastics) gives a fast, high-rate signal. High-intensity progressive resistance training (heavy squats, deadlifts, and presses at a high relative load) gives a high-magnitude one. Both build bone, particularly at the hip and spine.
Moderately osteogenic. Running and jogging. The impact is real, but lower and more repetitive than a jump.
Low osteogenic. Easy walking, light yoga, slow tai chi. These have real benefits for fitness, balance, and flexibility, but the load on the skeleton sits below the threshold for bone growth.
Non-weight-bearing. Swimming and cycling. The water and the bike carry your weight, so the skeleton is not loaded. Excellent for the heart and for joint-friendly movement, but not bone-building.
The practical takeaway: a program built around walking and swimming will not build bone density, even if you do it every day. To build bone, the program has to include impact loading, heavy resistance training, or both.
04 · The LIFTMOR finding
Heavy resistance training for women who cannot jump
For many postmenopausal women, jumping is not the right starting point. Knee pain, hip pain, balance concerns, or established osteoporosis with vertebral changes can all make impact loading unwise. The good news: a supervised heavy resistance training program builds bone density well, and is safe when prescribed correctly.
The landmark Australian evidence is the LIFTMOR trial, run at Griffith University. Postmenopausal women with low bone mass (T-score below -1.0) were randomised to either an 8-month, twice-weekly, supervised high-intensity resistance and impact training program (5 sets of 5 repetitions at more than 85 per cent of their one-repetition maximum) or a home-based, low-intensity exercise program. The high-intensity group showed significantly greater gains in lumbar spine and femoral neck bone density, along with better strength, balance, and functional movement, and a small gain in height where the comparison group lost height. The program was safe under supervision: across the whole trial there was only one minor adverse event, a brief lower-back spasm (Watson, Weeks and Beck, 2018, the LIFTMOR trial).
That mattered, because heavy lifting in women with osteoporosis had long been considered too risky. The LIFTMOR data showed that, when it is supervised by an Exercise Physiologist or Physiotherapist trained in the protocol, high-intensity training is both safe and effective for this group.
A few practical notes from the LIFTMOR protocol and its follow-on studies:
- The training was supervised in a clinic gym. This is not a “load up a bar at home” program.
- The load was high relative to the participant’s strength, not high in absolute terms. A 5-rep deadlift at 85 per cent of one-rep max is the right intensity even if the absolute weight is modest.
- The program screened for fracture risk before starting. Women with severe established vertebral osteoporosis or specific movement concerns followed a modified protocol.
- Deep forward flexion of the spine under load is avoided in known vertebral osteoporosis, so no weighted rowing, no weighted sit-ups, and no deep forward folds under load (ESSA 2017).
05 · Where to start
Where to start and who supervises the program
If you have low bone density, established osteoporosis, a previous minimal-trauma fracture, or you are looking to protect your bones through menopause and your 60s, the right first step is a clinician-led assessment.
An Exercise Physiologist or Physiotherapist will:
- Review your DEXA scan, fracture history, and current medications.
- Screen for movements to avoid, such as deep spinal flexion under load or twisting under load in known vertebral osteoporosis.
- Test your current strength, balance, and functional movement.
- Prescribe a program at the right tier of loading for your bone density, fitness, and goals.
- Supervise the first sessions and progress the load as you adapt.
If impact loading is appropriate, you will start with low-amplitude impact (heel drops, low hops) and progress to higher-rate impact over weeks. If heavy resistance training is the right entry point, you will start with bodyweight and light resistance and build to LIFTMOR-style loading over months.
The program runs in parallel with the rest of your bone-health plan: adequate calcium and vitamin D, fall-prevention work at home, a footwear review with a Podiatrist if needed, and any medication your GP has prescribed.
