Using Wearable Technology To Predict Physiological And Psychological Indicators Of Health And Performance In Swimmers

Abstract

Athletes can have difficulty meeting energy requirements to fuel performance due to intense training for extended durations. Mismatched energy intake and expenditure, i.e., low energy availability (EA) can affect health and performance, as can psychological stress associated with sport or daily life. Measures from wearable technology may be surrogate indicators of low EA and stress, allowing for health and performance optimization. PURPOSE: Determine effectiveness of wearable technology for use in detection of physiological (EA) and psychological (stress) variables related to health and performance in elite swimmers. METHODS: We used a wrist worn wearable device to test if measures in male (n = 10) and female (n = 13) NCAA Division 1 swimmers (Age 20 ± 1 yr; BMI 23 ± 2 kg/m2; Body Fat % 21 ± 5%) during heavy training preceding championship competition were associated with validated measures of metabolic health and psychological stress. Wearable measures of heart rate variability (HRV) and Strain were compared to laboratory measures of resting metabolic rate (RMR), total triiodothyronine and validated surveys assessing lifestyle and sport stress ((Perceived Stress Scale (PSS), RESTQ-52 Sport (RESTQ)). Swimmers were grouped by degree of metabolic adaption to low EA using the ratio of actual to dual energy X-ray absorptiometry (DXA) predicted RMR (< or > 0.94). RESULTS: Wearable HRV was lower in swimmers with DXA RMR ratio < 0.94 (n = 12) vs. those with higher RMR ratios (n = 11) (81 ± 27 ms vs.110 ± 35 ms, p < 0.05). HRV correlated with RMR/LBM (kcal·kg-1·day-1) in all athletes (r = 0.45; p < 0.05). Regarding prediction of lifestyle and sport stress, sex-specific correlations between HRV and lifestyle stress (PSS) were found in males (r = -0.68; p < 0.05). Wearable Strain was negatively associated with RESTQ total recovery stress balance in males (r = -0.69; p < 0.05), and male HRV was negatively correlated with RESTQ general stress (r = -0.72; p < 0.05), total stress (r = -0.74, p < 0.05) but not sport stress (r = -0.60; p > 0.05). No correlations between HRV or Strain and stress variables (RESTQ) were observed in females. CONCLUSION: Wearable technology may be effective in identifying low EA in male and female swimmers and effective in identifying lifestyle stress in males, thereby providing insights into swimmers' health and performance.