Nutrition factors associated with rib stress injury history in elite rowers

OBJECTIVES:To investigate associations between nutrition factors (diet restriction, menstrual status, calcium intake, vitamin D and K status), bone mineral density (BMD) and rib stress injury (RSI) history. DESIGN:Cross-sectional. METHODS:133 elite rowers completed a self-report questionnaire to collect information regarding training and injury history, menstrual status and diet restriction, and a calcium intake questionnaire (SCQ2002). BMD and body composition were assessed by dual-energy X-ray absorptiometry. A sub-group (n = 68) had vitamin D and K status assessed from fasted morning blood. History of RSI was self-reported and verified against medical records. Characteristics of injured and uninjured rowers were compared (one-way ANOVA), while relationships with BMD (multiple linear regression) and RSI (multiple logistic regression) were modelled. RESULTS:Diet restriction was inversely related to spine BMD and rib BMD. Within sex, vitamin D and K status, and calcium intake were not associated with injury. Among rowers with RSI history, lightweight males had lower total bone mass, femur BMD and rib BMD, whereas heavyweight females had lower rib BMD. In relation to RSI history, the best models included rib, spine or femur BMD with age, body fat and sex. A female-specific model included rib BMD, current menstrual dysfunction, age and body fat levels. CONCLUSIONS:BMD, including that of the rib, diet restriction, menstrual function and weight category were associated with rib injury history and should be considered in the management of elite rowers.