Osteoporosis: Lifting Weights for Bone

Written by INNER G

November is Osteoporosis Month in Canada. Osteoporosis Canada says more than 2.3 million Canadians live with the disease, and at least 1 in 3 women and 1 in 5 men will suffer a fragility fracture, which is the term for a break linked to weak bones, in their lifetime (Osteoporosis Canada, n.d.).

Lifting weights comes up a lot when people ask what they can do about it. The research is more mixed than most posts let on. This one goes through the 2023 Canadian guideline and the trials behind it, then what a sensible start looks like in the studio.

Please read first. This post is general information, not medical advice. If you've been diagnosed with osteoporosis or low bone density, or you've had a fracture, talk to your doctor before you change how you train. If something hurts sharply during an exercise, stop and get medical care.

What the Canadian guideline says

The 2023 Canadian guideline on osteoporosis and fracture prevention gives two exercise recommendations that matter most here (Morin et al., 2023):

  • Balance and functional training at least twice a week to lower the risk of falls. This is a strong recommendation backed by moderate certainty evidence.
  • Progressive resistance training at least twice a week, including exercises for the abdominal and back extensor muscles. This is a conditional recommendation. The evidence behind it is low certainty.

"Progressive" means you add weight, reps, sets or difficulty over time. The guideline adds that many resistance exercises count as functional exercises too.

It also says walking, impact exercise, yoga and Pilates are fine if you enjoy them and they can be done safely. They should come in addition to balance, functional and resistance training, not instead of it (Morin et al., 2023). Our post on balance exercises and fall prevention covers the balance half.

What happened in one heavy lifting trial

One trial gets talked about more than any other. It's called LIFTMOR. It randomized 101 postmenopausal women with low bone mass to 8 months of one of two programs (Watson et al., 2018).

The lifting group trained twice a week for 30 minutes under close supervision, doing 5 sets of 5 repetitions at more than 85% of their one repetition maximum. The comparison group followed a low intensity program on their own.

Bone density change in the LIFTMOR trial

Average change over 8 months in women with low bone mass. Gold is the supervised heavy lifting group. Grey is the low intensity comparison group. Pick a bone site.

Supervised heavy lifting, 49 women

Low intensity program, 52 women

Loss of bone density0%Gain

Source: Watson SL, et al. J Bone Miner Res 2018;33(2):211-220. Read the study. Lifting group: 2 sessions a week, 30 minutes, 5 sets of 5 repetitions at more than 85% of a one repetition maximum, supervised. Comparison group: a low intensity program done on their own. Bars show average percent change. This was one small trial. It measured bone density, not broken bones.

Lumbar spine bone density rose 2.9% in the lifting group and fell 1.2% in the comparison group. At the femoral neck it rose 0.3% versus a 1.9% drop. Only one adverse event was reported in the lifting group, a minor lower back spasm (Watson et al., 2018).

A second paper from the same trial scanned the spine for new fractures. The lifting group had no change in vertebral fracture classification, and one new wedge shaped deformity showed up in the comparison group (Watson et al., 2019).

Read this one carefully. It was a single trial. The women were otherwise healthy and screened first. The training was highly supervised, and the authors say that is the condition under which it worked. It measured bone density, not broken bones.

What the reviews found

Pooling many trials gives a steadier picture. Here is how the main reviews line up.

  • Cochrane, 2011: 43 trials with 4,320 postmenopausal women. High force exercise that doesn't bear body weight, such as progressive resistance training for the legs, looked best for the femoral neck (mean difference 1.03, 95% CI 0.24 to 1.82), and combined programs looked best for the spine (3.22, 1.80 to 4.64). The reporting quality of the trials was low (Howe et al., 2011).
  • Systematic review, 2021: 53 trials of progressive resistance training in people with low bone density or a past fracture. It may raise femoral neck density slightly (0.02 g/cm2) but showed no clear change at the lumbar spine. It also improved quality of life and the Timed Up and Go test, and it reduced pain. Adverse events were rare and often minor (Ponzano et al., 2021).
  • Kelley, 2012: small gains at the femoral neck and lumbar spine from lifting and impact exercise in women who weren't active. The authors estimated those changes could lower 20 year fracture risk by about 11% and 10%. That is a modelled estimate, not something the trials observed (Kelley et al., 2012).
  • Zhao, 2015: lifting combined with impact or weight bearing exercise worked. Lifting alone gave gains that weren't statistically significant (Zhao et al., 2015).
  • Zhao, 2025: 17 trials with 690 women. Larger effects on the lumbar spine and femoral neck, but the trials disagreed a lot with each other (I2 of 91% and 87%) (Zhao et al., 2025).

What reviews of exercise trials found for bone density

Each dot is a review's pooled estimate for women after menopause. Kelley pooled trials of lifting and impact exercise. The Zhao reviews pooled lifting programs. The line is the 95% confidence interval. If the line touches the black zero line, that result wasn't clearly different from no change. Pick a bone site.

Sources: Kelley GA, et al. BMC Musculoskelet Disord 2012;13:177 (study). Zhao R, et al. Osteoporos Int 2015;26(5):1605-1618 (study). Zhao F, et al. J Orthop Surg Res 2025;20:523 (study). Units are standardized mean differences, so bigger numbers mean a bigger gap between lifting and control groups, not percent. The 2025 review had much higher heterogeneity (I2 of 91% and 87%), so its larger numbers are less certain.

Where the evidence disagrees

The reviews don't agree on the details, and that's worth saying plainly.

  • How hard. A 2023 network analysis of trials ranked moderate intensity training 3 days a week as best, ahead of low and high intensity (Wang et al., 2023). The 2025 review found training at 70% of a one repetition maximum or more worked at the femoral neck and total hip (Zhao et al., 2025). LIFTMOR got its spine results at more than 85%, in one closely supervised trial.
  • How long. The 2023 network analysis found its advantage was no longer significant past 48 weeks, and its authors advised against going longer than a year (Wang et al., 2023). The 2025 review found that programs of 48 weeks or more did help the femoral neck and hip (Zhao et al., 2025). The guideline doesn't set an end date.
  • The spine. The 2021 review found no clear lumbar spine change, while most of the others did (Ponzano et al., 2021).

Nobody can say which review is right. They pooled different trials with different designs, and heterogeneity was high in several. What they share is the direction. None of them found that lifting hurt bone density, and most found a small gain.

What lifting hasn't been shown to do

No trial in these reviews showed that lifting weights prevents broken bones. The Cochrane review found no effect on the number of fractures (odds ratio 0.61, 95% CI 0.23 to 1.64, a range that includes no effect) (Howe et al., 2011). Bone density is a marker for fracture risk, not the same thing.

Most of the trials above were in women after menopause, so they tell us less about men. And lifting doesn't replace osteoporosis treatment. If your doctor has talked to you about medication, keep that conversation going alongside training.

Protect your spine

The guideline has a good practice statement on this. Activities that involve rapid, repetitive, sustained, weighted or end range twisting or flexion of the spine may need to be modified, especially if you're at high risk of fracture (Morin et al., 2023). It also says that if your fracture risk is high or you've recently had a fracture, you should seek advice from exercise professionals with training in osteoporosis, when you can (Morin et al., 2023).

So tell your coach about your diagnosis or any past fracture before the first session, so exercises that load or twist the spine can be changed. If that's your situation, ask us before you book. We'll talk through what fits, and if your doctor wants you with a specialist first, start there.

What about supplements

The guideline looked at supplements too. For people who eat a balanced diet and aren't on osteoporosis medication, it says calcium and vitamin D supplements, and protein supplements too, likely have little to no effect on fractures. It suggests getting your calcium from a variety of calcium rich foods and following Health Canada's advice on vitamin D (Morin et al., 2023). We went through the vitamin D side in our post on vitamin D in winter. If you want help sorting out your food, our nutrition coaching is designed around that.

How often to train

The guideline suggests at least 2 days a week of resistance work and at least 2 days of balance and functional work. A single class can cover both if the coach programs both. Tap your days below to see how your week compares.

Compare your week with the guideline

The 2023 Canadian guideline suggests progressive resistance training and balance and functional training, each at least twice a week. Tap the days you train with a coach in the studio. A class can count for both if it includes both.

MTWTFSS
Strength
Balance

Source: Morin SN, et al. CMAJ 2023;195(39):E1333-E1348 (guideline). Recommendations 1.1 and 1.2. The balance recommendation is strong. The resistance training one is conditional, based on low certainty evidence. This tool is not a medical assessment. Talk to your doctor before you change your training.

What to do this month

  1. Book a conversation first. Tell the coach what your doctor has said and whether you've had a fracture.
  2. Pick a progressive plan. Start with weights you can control, and add load or reps in small steps over weeks.
  3. Train twice a week at minimum. Make sure the plan has back extension work and balance work, along with the main lifts.
  4. Skip the fast twisting. Ask the coach to swap out anything that flexes or twists your spine hard.
  5. Keep walking and anything else you enjoy. It counts, as long as it sits next to the lifting and doesn't replace it.

Come lift in the studio with a coach in Vaughan

This is what coaching is for. A coach can set the weight for you and change an exercise on the spot if it doesn't suit you.

Start with our small group classes. Each class is capped at 16 people, and the studio is open from 5:45 AM to 8 PM on weekdays and from 8:30 AM to 4 PM on weekends, with parking on site.

If you want more attention, try personal training in Vaughan. We also offer one on one training focused on balance and strength.

Try the $30 seven day trial (+ HST). Join by day 5 and your $30 is credited toward your membership.

Call (289) 536-8066 or email g-squad@innerg.ca.

References

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