Low Vertebral Bone Density Values in Young Non-Elite Female Runners

Abstract

Thirty-five female runners (26.6 ± 0.9 years, range 17-35) were scheduled for bone mineral density evalation, using quantitative computed tomography of the lumbar spine. In 17 women with oligo-amenorrhea, vertebral bone mineral density was under the normal range (defined from a control group of 46 sedentary healthy females in the same age range), while it was within the normal range in all runners with regular menses (n = 18). When age classes were considered, all runners aged 17-21 (11/11) were found to have oligo-amenorrhea and low bone mineral density values, the difference in mineral density with the controls of the same age quartile being highly significant (p < 0.001). Runners from the two youngest age classes (17-21 and 22-26) had started training early after menarche (0.9 + 0.6 and 2.5+1.6 years, respectively). These results show that very young female runners with oligo-amenorrhea may have impressively low bone mineral density values. The possibility that early onset of training, close to menarcheal age, might be a risk factor for low mineral density, deserves further investigation.

Key words

Female runners - menstrual disorders - vertebral bone mineral density