What Bone Density Scans Can't Tell You About Fracture Risk | A Masterclass on Bone Health

What It Covers

Researchers and clinicians explain why bone mineral density scans capture only 70% of fracture risk, how aging, bone geometry, and fall probability contribute to the remaining risk, and what resistance training protocols — including load selection, rep ranges, and impact exercises — can preserve bone strength across the lifespan.

Key Questions Answered

• •Fracture Risk Calculation: BMD accounts for roughly 70% of fracture risk, but physicians use the FRAX algorithm — combining age, bone density, fall history, and other independent risk factors — to calculate a 10-year fracture probability percentage. Two people with identical femoral neck BMD scores can carry meaningfully different fracture risk based on age and comorbidities alone, making FRAX a more clinically useful decision tool than a DEXA scan in isolation.
• •Bone Geometry vs. Density: DEXA measures areal bone mineral content divided by scan area — not true volumetric density — and cannot distinguish cortical from trabecular bone or capture structural shape. Research from the LIFTMORE trial showed that high-intensity lifting thickened the femoral neck cortex without significantly changing BMD scores. A wider, thicker bone resists bending forces better than a denser but narrower one, meaning geometry improvements can be missed entirely when only tracking standard DEXA output.
• •Blood Markers for Bone Remodeling: CTX measures bone resorption activity and P1NP measures bone formation. Physicians use these markers to detect abnormal remodeling rates, monitor whether anti-resorptive medications are working, and flag sudden bone loss — but neither marker indicates total bone quantity. They function as process indicators, not status indicators, and should be used alongside DEXA rather than as a replacement for it.
• •Resistance Training Load and Rep Range: Current evidence does not conclusively establish that very low reps at maximum load outperform moderate loads for bone adaptation. The 8–12 rep range at challenging but manageable intensity allows sufficient movement practice, proximity to failure, and reduced injury risk — particularly for beginners whose form under near-maximal loads may be inconsistent. Difficulty level relative to the individual, not absolute load, determines the mechanical stimulus delivered to bone.
• •Combining Strength and Impact Training: For women with osteopenia or a family history of osteoporosis, adding pogo hops or small jump-landing sequences to a resistance training program shows bone density improvements in year-long trials. Strength training remains the primary intervention, but 2–3 sets of 10–12 low-amplitude hops performed several times per week can complement it. Individuals with pelvic floor or knee issues should prioritize the strength component and introduce impact gradually.
• •Fall Prevention as Fracture Strategy: Reducing fracture risk requires both stronger bones and a lower probability of falling. Incorporating unilateral movements — single-leg squats, step-ups with controlled eccentric lowering, walking lunges — into resistance training builds the reactive strength needed to catch a stumble. Maintaining multi-planar movement through activities like pickleball, hiking on uneven terrain, or dancing preserves the coordination and spatial awareness that bilateral gym exercises alone do not train.