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A competitive sport season represents a multidimensional stressor where physical and psychological stress may render an athlete susceptible to energy deficiency (ED). Downstream effects of ED can include a reduction in measured-to-predicted resting metabolic rate (RMR ratio ), indicating metabolic compensation. A pathway linking stress, eating attitudes, and metabolic compensation has not been explored. To test if sport-specific stress is associated with eating attitudes and metabolism in endurance athletes (18-22 years) at different phases of a competitive season, we assessed two groups of athletes: 26 swimmers (15 female and 11 male) during peak season (PEAK), and 26 runners (female) across pre- (PRE) and off-season (OFF). Stress (RESTQ-52), eating attitudes (cognitive restraint (CR), drive for muscularity (DM), and body dissatisfaction), and metabolism (RMR ratio ) were assessed. In PRE, sport-specific stress and CR were negatively correlated with RMR ratio ( R = -0.58; p  < 0.05, and R = -0.57; p  < 0.05, respectively). In PEAK, sport-specific stress and DM were negatively correlated with RMR ratio ( R = -0.64; p  < 0.05; R = -0.40; p  < 0.05, respectively). DM was positively related to sport-specific stress ( R  = 0.55; p  < 0.05). During OFF, there was no relation between RMR ratio and sport-specific stress. In runners, there was a change in stress from PRE-to-OFF with highest reported stress during PRE ( p  < 0.05) versus OFF. Regression analyses revealed that sport-specific stress and CR were significant predictors of RMR ratio during PRE and PEAK ( p  < 0.05), but not OFF ( p  > 0.05). Associations between stress, eating attitudes, and metabolic compensation in endurance athletes during PRE and PEAK season suggest that during heavier training, metabolic compensation may be linked to upstream eating attitudes associated with sport-stressors., Competing Interests: The authors declare there are no competing interests.

To determine whether mismatched energy intake and expenditure across the day and associated sex differences may be related with metabolic compensation and/or negative health outcomes, we assessed total-day and hourly energy balance (TDEB and EB), total-day and hourly energy intake (TDEI and EI), total-day and hourly energy expenditure (TDEE and EE) and within-day energy balance (WDEB) in elite male and female swimmers ( n  = 25; 18-22 years). Total triiodothyronine (TT 3 ), resting metabolic rate (RMR), and the ratio of actual-to-predicted RMR were determined. Males exhibited higher TDEB (+758 ± 702 kcal vs +52 ± 505 kcal, t -test; p  = 0.007) than females. Males exhibited a more positive hourly EB, driven by greater hourly EI at 11:00, 13:00, 16:00, and 19:00 h (ANOVA, p  < 0.05), while EE did not differ. TT 3 was negatively correlated with consecutive hours of negative EB ( R = -0.604, p  = 0.049) and positively correlated to hours in EB ( R  = 0.740, p  = 0.009) in those exhibiting metabolic suppression ( n  = 12). In individuals in TDEB ( n  = 21), "backloaders" (consumption of ≥50% daily kcals at or after 1700 h) had lower TT 3 (79.3 ng/dL vs 92.9 ng/dL, p  = 0.009) than "nonbackloaders" ( n  = 12). WDEB analyses indicate a greater risk of energy deficiency in females and may capture indices of metabolic compensation not evident with EB analyses alone.