Boston Marathon Prospective Study: Medical And Performance Outcomes Associated With Indicators Of Low Energy Availability

PURPOSE: To evaluate association between indicators of problematic Low Energy Availability (LEA), i.e. LEA of long duration and/or severity, and race performance and medical outcomes of athletes participating in the 2022 Boston Marathon. METHODS: Registered entrants (age ≥ 18 yr) for the 2022 Boston Marathon were recruited to complete an encrypted electronic pre-race survey (1-4 weeks pre-event), with de-identified responses related to training, nutrition, and performance history. Questionnaire data was linked to official race timing and medical encounter data from the marathon. Female LEA indicators included: total EDE-Q scores (>2.3), and/or a total LEAF-Q score (≥8), and/or self-report of diagnosed Eating Disorder/Disordered Eating (ED/DE). Male LEA indicators included: total EDE-Q scores (>1.68), and/or self-report of diagnosed ED/DE, and/or for male participants <50 yrs of age: a low sex drive score based on 3 questions from the LEAM-Q subsection on reproductive dysfunction. RESULTS: Of 1,030 study participants (F: 546, M: 484), (ages F: 43.5 ± 10.3 yrs, M: 51.5 ± 10.7 yr; mean ± SDs), 30.4% (42.5% of females and 17.6% of males) were identified with problematic LEA indicators based on validated scoring criteria. Both females and males with LEA indicators finished with significantly worse (mean age- and sex-matched) Boston Marathon division place rankings compared to healthy controls (Females: 1377.4 ± 82.9 vs. 948.9 ± 57.6, p < 0.001; Males: 1262.4 ± 103.3 vs. 794.6 ± 41.0, p < 0.001 respectively). Overall, athletes with indicators of problematic LEA had a 1.95-fold greater relative risk (CI: 1.13-3.36, p = 0.017) of requiring medical support for any condition compared to healthy controls, and a 3.55-fold greater relative risk (CI: 1.17-10.76, p = 0.025) of a significant medical event (i.e., did not finish requiring intra-event medical transportation or transfer to a local hospital from a course medical tent, or transport to a hospital from the post-finish medical area). CONCLUSIONS: This is the first large questionnaire-based study on problematic LEA where the outcomes could be directly linked to real-world performance and medical consequences in a specific competition. Our novel findings confirm the performance and health implications of problematic LEA in both female and male athletes.