High femoral bone mineral content and density in male football (soccer) players

Abstract

Purpose: This investigation examined the effect that long-term football (soccer) participation may have on areal bone mineral density (BMD) and bone mineral content (BMC) in male football players. Methods: Dual energy x-ray absorptiometry (DXA) scans were obtained in 33 recreational male football players active in football for the last 12 yr and 19 nonactive subjects from the same population. Both groups had comparable age (23 ± 4 yr vs 24 ± 3 yr), body mass (73 ± 7 kg vs 72 ± 11 kg), height (176 ± 5 cm vs 176 ± 8 cm), and calcium intake (23 ± 10 mg·kg−1·d−1 vs 20 ± 11 mg·kg−1·d−1 (mean ± SD). Results: The football players showed 8% greater total lean mass (P < 0.001), 13% greater whole-body BMC (P < 0.001), and 5 units lower percentage body fat (P < 0.001) than control subjects. Lumbar spine (L2–L4) BMC and BMD were 13% and 10% higher, respectively, in the football players than in the control subjects (P < 0.05). Furthermore, football players displayed higher femoral neck BMC (24%, 18%, 23%, and 24% for the femoral neck, intertrochanteric, greater trochanter, and Ward’s triangle subregions, respectively, P < 0.05) and BMD (21%, 19%, 21%, and 27%, respectively, P < 0.05) than controls. BMC in the whole leg was 16–17% greater in the football players, mainly because of enhanced BMD (9–10%) but also because of bone hypertrophy, since the area occupied by the osseous pixels was 7% higher (867 ± 63 cm2 vs 814 ± 26 cm2, P < 0.05). Leg muscle mass was 11% higher in the football players than in the control subjects (20,635 ± 2,073 g vs 18,331 ± 2,301 g, P < 0.001). No differences were found between the legs in either groups for BMC, BMD, and muscle mass. Left leg muscle mass was correlated with femoral neck BMC and BMD (P < 0.001), as well as with lumbar spine (L2–L4) BMC and BMD (P < 0.001). Conclusion: Long-term football participation, starting at prepubertal age, is associated with markedly increased BMC and BMD at the femoral neck and lumbar spine regions.