Bone Density, Osteoporosis and Arthritis: What Women Should Know Before 40

This is not a comfortable subject, and we are not going to make it one. Osteoporosis is common, largely preventable, and most women only learn about it after the first fracture. By that point the useful window has closed. ### The timeline nobody explains You reach **peak bone mass in your late twenties**. After roughly age 35, bone is lost faster than it is rebuilt. That process is slow at first. Then menopause arrives. Oestrogen protects bone, and when it falls, loss accelerates sharply — women can lose a meaningful share of their bone density in the first five to seven years after menopause. Nothing about this feels like anything. There are no symptoms. Bone density is not routinely measured until something breaks. This is why osteoporosis is described as a silent disease, and why the first sign for many women is a wrist fracture from a trip, or a vertebral compression fracture from something as ordinary as lifting a suitcase. ### Why this matters more than it sounds A hip fracture in later life is not a broken bone. It is a life event. Outcomes after hip fracture in older adults are genuinely poor — a substantial proportion never recover their previous independence, and mortality in the year following is significantly elevated. The fracture is rarely the thing that does the damage; the immobility that follows it is. And the risk is not evenly distributed. Women are affected considerably more often than men, because of both lower peak bone mass and the menopausal drop. ### Arthritis is a different problem, often confused with this one Osteoporosis is loss of bone density. Osteoarthritis is degeneration of joint cartilage. They are unrelated conditions, and the advice people give about them tends to be exactly backwards. The common belief is that if your knees or hips hurt, you should rest them and avoid loading. For most osteoarthritis, the evidence points the other way: **appropriate loading is a treatment, not a risk.** Cartilage has no blood supply of its own and depends on movement to exchange nutrients. Muscle around an arthritic joint is what absorbs the force the cartilage no longer handles well. Strength training is one of the better-supported interventions for knee osteoarthritis pain. The women we see who are worst affected are usually the ones who were told to stop moving a decade earlier. ### What actually builds bone Only two stimuli reliably tell bone to become denser: **mechanical load** and **impact**. That is the entire list. Walking helps maintain what you have but is too low-load to build. Swimming and cycling, whatever else they do for you, do almost nothing for bone because the load is not transmitted through the skeleton. What works: - **Progressive resistance training.** Loaded squats, deadlifts, presses and rows, made progressively heavier over time. The load has to be meaningful — light weights for high repetitions do not provide the stimulus. - **Impact, where appropriate.** Step-downs, hops and low-level jumping load bone in a way that resistance work alone does not. This has to be introduced according to what the individual can tolerate. - **Balance and strength together.** The other half of fracture prevention is not falling. Single-leg strength, ankle stability and reaction are what keep you upright. - **Protein and vitamin D.** Bone is roughly half protein by volume. You cannot build the matrix without the raw material. ### The part that should motivate you Bone responds to load at any age. Studies of resistance training in postmenopausal women have shown maintained and in some cases improved bone density — in a population that would otherwise have been losing it steadily. Starting at fifty is very much worth doing. But the arithmetic favours starting earlier. Bone you build in your thirties is bone you are not trying to claw back in your sixties, and the building is far easier than the clawing back. ### What we do about it Every BYLDUP engagement opens with an assessment — range of motion, postural loading, balance, left-to-right symmetry, core endurance under time. For women training with bone health in mind, that baseline shapes a programme built on progressive loading rather than on burning calories. If you have a diagnosed condition — osteoporosis, osteopenia or significant arthritis — we coach alongside your doctor or physiotherapist rather than in place of them, and we want to know about it before the first session, not after. *This article is general information, not medical advice. If you are concerned about your bone density, ask your doctor about a DEXA scan.*