A Systematic Review of Bone Health in Cyclists

Area of Science:

• Orthopedics
• Sports Medicine
• Public Health

Background:

• Low bone mineral density (BMD) is a significant public health concern, increasing fracture risk.
• Weight-bearing exercise positively impacts BMD, while non-weight-bearing exercise shows less benefit.
• Cycling, a weight-supported activity, raises questions about its effect on bone health.

Purpose of the Study:

• To systematically review existing evidence on bone health in cyclists.
• To investigate potential impairments in bone mineral density (BMD) at the femoral neck and lumbar spine among cyclists.

Main Methods:

• A systematic literature search was conducted across PubMed, Cochrane Library, and CINAHL databases.
• Included studies comprised 2 prospective and 11 cross-sectional designs.
• Data extracted included sample characteristics, exercise details, and BMD measurements.

Main Results:

• Prospective studies indicated a decrease in BMD (femoral neck, hip, or lumbar spine) in cyclists over time.
• Cross-sectional studies comparing cyclists to sedentary individuals showed mixed results, with one study reporting lower BMD in cyclists.
• Comparisons with active controls (e.g., runners) revealed that cyclists often had lower lumbar spine BMD.

Conclusions:

• Limited, low-quality evidence suggests cyclists may be at risk for low bone mass, especially at the lumbar spine.
• The findings are concerning but inconsistent, primarily based on cross-sectional data.
• Further high-quality, longitudinal controlled intervention trials are necessary to confirm these risks.