The focus of this prospective, observational study was to determine the effect of sport-specific training and calcium intake on bone mineral density (BMD) in female master cyclists, runners and non-athletes. Thirty women (12 cyclists, 9 runners, 9 controls), mean age of 49.6 ±7.9 years, were assessed at baseline and 18 months for calcium intake (4-day records), current exercise activity (recall questionnaire), and BMD of the lumbar spine and hip (DXA). A three (cyclists, runners, controls) by two (0 and 18 months) repeated measures ANOVA demonstrated a significant interaction effect of sport and time at the femoral neck (p < .04). Tukey post hoc analysis indicated that the BMD of the femur was maintained in cyclists and runners but declined in controls (p < .05). A significant time effect was noted in BMD at the lumbar spine (p < .001) and the trochanter (p < .003). BMD of the lumbar spine was maintained in runners but declined in cyclists (p < .007) and in controls (p < .03), while trochanteric BMD declined in all groups (p < .01). No significant interaction effect of sport and dietary calcium intake was noted for BMD at any site.
The authors are with the Department of Exercise and Nutritional Sciences at San Diego State University, San Diego, CA 92182-7251. Address all correspondence to Dr. Beshgetoor.