Objective: To investigate factors associated with menstrual dysfunction, self-reported bone stress injuries and energy balance in women runners.
Methods: 613 runners were randomly sampled during the registration period for an endurance event. Demographic information including self-reported height and weight, training and injury history, and menstrual history, were collected via questionnaire.
Results: ULTRA subjects (n=276) were significantly older (p<0.001), lighter (p<0.05) and reported a higher training volume (p<0.001) than HALF subjects (n=337). Significantly more ULTRA subjects than HALF subjects reported a previous bone stress injury (21 vs. 14%; p<0.05). There was no difference between the groups for menstrual status, however age at menarche was later (p<0.01) in the ULTRA group. Data was combined according to the absence (REG: n=368, 61%) or presence (IRREG: n=234, 39%) of a history of menstrual irregularity. Subject morphology was similar between groups, however the IRREG group scored higher on a self-reported measure of self-loathing (SLSS; p<0.01). The whole group was then classified according to current menstrual status with 55 women being classified as currently irregular (OLIGO/AMEN; 11.6%) and 416 women as currently regular (EUMEN; 88.4%). There were no morphological differences between the groups, however the OLIGO/AMEN group had a later age of menarche (p<0.01) than the EUMEN group. Further, women who reported a previous bone stress injury had higher SLSS scores than those who did not (p<0.05).
Conclusions: These findings suggest that there may be two independent mechanisms, associated with energy balance, which are related to bone stress injuries, but may not necessarily be related to menstrual dysfunction.
- energy balance
- menstrual dysfunction