High bone mineral density in male elite professional volleyball players

The aim of this study was to assess bone mass in male elite athletes partic ipating in an impact loading sport (volleyball) and, in particular, to dete rmine whether the asymmetric nature of this sport leads to differences in t he skeletal tissue composition of the limbs. Fifteen male volleyball player s (VP) (26 +/- 4 years, 192 +/- 6 cm, 87 +/- 9 kg; mean +/- SD) and 15 non- active control subjects (25 +/- 2 years, 177 +/- 8 cm, 72 +/- 11 kg; mean /- SD) were studied. VP training sessions (3-6 days/week) included a variet y of jumping and weightlifting exercises. The VP were taller and heavier th an the control subjects (p<0.001). Whole-body bone mineral content (BMC) an d lean mass were higher in VP after adjustment for body mass and height (p< 0.001). Axial skeleton and limb BMC and bone mineral density (BMD) were hig her in VP than in control subjects (p<0.05). Adjusted lumbar spine (L2-4) B MD was 14% higher in VP than in control subjects (p<0.05). Similarly, a muc h greater adjusted BMD was observed in the femoral neck of VP (24%, 20%, 27 % and 20% for the femoral neck, intertrochanteric, greater trochanter and W ard's triangle subregions respectively; p<0.05). The dominant ann was sligh tly heavier (approximate to 3%) and had 4% more muscle mass than the contra lateral arm in both the VP (p<0.05) and control subjects (p<0.05). Greater BMC values (9%), BMD (7%) values and the area occupied by osseous pixels (5 %) were recorded in the dominant arm as compared with the nondominant arm i n VP (p<0.05). No differences between arms were observed in control subject s. Right and left leg BMC and BMD values were similar in control subjects w hile 4% higher BMC values were recorded for the left leg in the VP group (p <0.05). A close relationship between left leg muscle mass and BMD was obser ved in the femoral neck subregions of all the subjects (r = 0.81, 0.81, 0.7 8 and 0.79 for the femoral neck, intertrochanteric, greater trochanter and Ward's triangle subregions respectively; p<0.001; n = 30). These findings c learly demonstrate a considerably high BMC and BMD in professional volleyba ll players which seems to be related to the loading type of exercise they p erform.