The Influence of Sleep and Heart Rate Variability on the Occurrence of Injuries, Illnesses, and Missed Participation Days in NCAA Collegiate Swimmers

Open Access
Armwald, Bruin Craig
Graduate Program:
Master of Science
Document Type:
Master Thesis
Date of Defense:
March 23, 2018
Committee Members:
  • Sayers John Miller III, Thesis Advisor
  • Giampietro Luciano Vairo, Committee Member
  • William M. Adams, Committee Member
  • David Hamilton, Committee Member
  • Sleep
  • Heart Rate Variability
  • Athlete
  • Swimming
  • Injuries
  • Illnesses
  • Missed Time
Athlete populations are at an increased risk of suffering an injury or illness due to their high level of physical activity. Additionally, athletes may not attain adequate bodily recovery following their training and/or competition sessions. This is particularly true of collegiate athletes who balance the demands of their sport with academic responsibilities. Recent innovations in wearable technology have allowed researchers to track specific recovery metrics such as sleep and heart rate variability. This study utilized the WHOOP Performance Optimization System to measure sleep and heart rate variables in a group of 11 NCAA Division 1 swimmers (Males= 8, Females= 3) for the duration of their season. Data related to covariables including training load and body composition were also recorded. Outcomes of interest were injuries, illnesses, and missed participation days. Descriptive statistics as well as stepwise logistical regression were used to discern the influence of predictor variables on the occurrence of adverse health events. Ten athletes completed data collection and were used for analysis. Average total sleep time was 6.51 (± 0.23) hours, and average HRV was 78.08 (± 7.54) ms. Regression analysis identified total sleep as a significant predictor of illnesses (OR= 0.70, 95% CI= 0.55-0.89, P< 0.01) and missed days (OR= 0.74, 95% CI= 0.61-0.90, P< 0.01). Hear rate variability was not identified as a significant predictor of any adverse events. Total yardage (OR= 0.99, 95% CI= 0.99-0.99, P< 0.001) and resting heart rate (OR= 1.08, 95% CI= 1.05-1.11, P< 0.001) were also identified as significant predictors of missed participation days. These results may be useful in assisting clinicians to make evidence-informed decisions regarding athlete training and recovery in order to reduce the risk of adverse health events. Additional research studies with greater sample sizes are necessary to confirm these preliminary findings.