Will running harm bone mineral density (BMD) in healthy adults?

Will Running Harm Bone Mineral Density?

No, running will not harm BMD in healthy adults—in fact, regular running maintains and may even improve bone density, particularly in the lumbar spine, though the benefits are modest compared to resistance training or high-impact exercise programs. 1, 2

Evidence for Running's Protective Effect on Bone

The evidence consistently demonstrates that running provides bone-protective benefits rather than harm:

• Longitudinal studies show runners maintain greater BMD over time compared to sedentary controls, with a 5-year study demonstrating that regular runners aged 55-77 years maintained significantly higher lumbar spine BMD despite age-related bone loss occurring in both groups 3

• Master runners (ages 40-80) maintain hip and spine BMD over 4-7 year periods, with bone density remaining stable even when training volume decreases moderately, suggesting a protective threshold effect below typical runner mileage 4

• The magnitude of bone preservation correlates directly with running volume, as changes in lumbar BMD show highly significant positive correlations with average weekly running time (minutes/week) over multi-year periods 3

Important Caveats About Running vs. Other Exercise

While running doesn't harm bones, it's not the most effective exercise for building bone mass:

• Running provides limited osteogenic stimulus compared to high-impact or resistance training, as weight-bearing exercise like running shows smaller BMD improvements than combination programs involving resistance training plus impact exercises 1, 2

• The most effective bone-building programs involve multiple exercise types, particularly combinations of resistance training and high-impact activities (jumping, hopping), which produce greater effects than running alone 1

• Optimal bone health programs require 60+ minutes, 2-3 times weekly for 7+ months, with resistance and multi-component programs showing standardized effect sizes of 0.15-0.17 for lumbar spine BMD 1, 5

When Running May Be Insufficient

Certain populations require more aggressive bone-loading strategies:

• Endurance athletes (distance runners, cyclists, swimmers) may have lower BMD than athletes in ball and power sports, and sometimes lower than inactive peers, due to high energy expenditure and insufficient bone-loading stimulus relative to metabolic demands 6

• Postmenopausal women and older adults show only mild BMD increases or maintenance with running alone, requiring combination approaches with resistance training, adequate calcium (1,000-1,200 mg/day), and vitamin D (800-1,000 IU/day) for optimal bone protection 7, 8, 2

• Substantial decreases in running volume are associated with accelerated bone loss, particularly in the lumbar spine, indicating that consistency matters more than peak training loads 3

Practical Algorithm for Bone Health in Runners

For healthy adults who run regularly:

• Continue running at current volumes (minimal threshold appears well below typical runner mileage) 4
• Add resistance training 2-3 times weekly on non-consecutive days targeting all major muscle groups 5
• Ensure adequate calcium (1,000-1,200 mg/day) and vitamin D (800-1,000 IU/day) intake 7
• Monitor BMD every 2 years if risk factors present 7

For those concerned about maximizing bone density:

• Incorporate high-impact activities (jumping, hopping) into training 2-3 times weekly 1, 2
• Prioritize resistance training with moderate-to-high intensity (8-12 repetitions, 1-2 sets) 5
• Maintain programs for minimum 7 months to achieve meaningful bone density improvements 1, 5

Red flags requiring intervention beyond running:

• FRAX 10-year risk ≥20% for major osteoporotic fracture or ≥3% for hip fracture 7
• T-score ≤-2.5 at any site (osteoporosis diagnosis) 7
• History of fragility fractures 7
• Chronic glucocorticoid use ≥2.5 mg/day prednisone for ≥3 months 7