Int J Sports Med 2020; 41(09): 589-595
DOI: 10.1055/a-1145-3754
Training & Testing

Heart Rate Variability in College Football Players throughout Preseason Camp in the Heat

1  Health Sciences and Kinesiology, Georgia Southern University – Armstrong Campus, Savannah, United States
2  Kinesiology, University of Alabama, Tuscaloosa, United States
,
Jeff Allen
3  Athletics, University of Alabama, Tuscaloosa, United States
,
Amy Bragg
4  Biological Sciences, University of Alabama, Tuscaloosa, United States
,
Clayton Keith
4  Biological Sciences, University of Alabama, Tuscaloosa, United States
,
Ryan Earley
4  Biological Sciences, University of Alabama, Tuscaloosa, United States
,
Michael R. Esco
3  Athletics, University of Alabama, Tuscaloosa, United States
› Author Affiliations

Abstract

We aimed to characterize cardiac-autonomic responses to a 13-day preseason camp in the heat among an American college football team. Players were categorized as linemen (n=10) and non-linemen (n=18). RHR, natural logarithm of the root-mean square of successive differences multiplied by twenty (LnRMSSD), and subjective wellbeing (LnWellness) were acquired daily. Effect sizes±90% confidence interval showed that for linemen, LnRMSSD decreased (moderate) on day 2 (71.2±10.4) and increased (moderate) on day 12 (87.1±11.2) relative to day 1 (77.9±11.2) while RHR decreased (small–moderate) on days 6, 7, and 12 (67.7±9.3–70.4±5.5 b∙min-1) relative to day 1 (77.1±10.1 b∙min-1). For non-linemen, LnRMSSD increased (small–large) on days 3–5, 7, 12, and 13 (83.4±6.8–87.6±8.5) relative to day 1 (80.0±6.5) while RHR decreased (small–large) on days 3–9, 12, and 13 (62.1±5.2–67.9±8.1 b∙min-1) relative to day 1 (70.8±6.2 b∙min-1). Decrements in LnWellness were observed on days 4–10 and 13 for linemen (moderate) and on days 6–9, 12, and 13 for non-linemen (small–moderate). Despite reductions in LnWellness, cardiac-autonomic parameters demonstrated responses consistent with heat-acclimation, which possibly attenuated fatigue-related decrements.



Publication History

Received: 00 00 2020

Accepted: 11 March 2020

Publication Date:
30 April 2020 (online)

© Georg Thieme Verlag KG
Stuttgart · New York