Tracking Fatigue With The Rpe Scale After A Standardized Submaximal Warm-up

Fatigue can influence the performance in negative way, especially when it is not adequately monitored and there is not an appropriate workload to rest ratio, thus resulting in non-functional overreaching and overtraining. PURPOSE: To investigate the relationship between Hooper index (HI) taken before training session and rate of perceived exertion (RPE) after a submaximal standardized warm-up in healthy active adults. METHODS: 15 subjects performed a 15-day training protocol with standardized warm-ups. Before all training sessions HI was administered, while at the end of the warm-up RPE was measured using the Borg category-ratio-10 scale. Subjects performed standardized 7-minute warm-ups at light intensity (30-39% heart rate reserve) including mobility (ankle, pelvis, wrist, arm) and aerobic exercises (jogging on place, jumping jack, running back and forth, kicking run, pungiball and side run). Relationship between HI and RPE responses were analyzed via linear mixed model (LMM)using HI and RPE values as fixed effects while the random effects were represented by the subjects’individual response. R-squared (R2) was calculated and likelihood-ratio test used to compare the LMM with the linear regression analysis. RESULTS: LMM (p=.015; R2=.20) had an estimated standard deviation for the random intercepts of 1.79AU (95%CI: 1.15-2.78) with standard error of .40.Likelihood-ratio test showed that LMM offered a significant (Chi2:30.96; p<.0001) improvement over a linear regression with only fixed effects, meaning that the intercepts were significantly different between subjects. To clarify the relationship between RPE and HI, combining the fixed and random intercepts, an equation was developed: HI = 8.30 + 0.79 x RPE + U0j+ ɛi CONCLUSIONS: The results of this study demonstrate that HI and post warm-up RPE change in parallel during periods of increased training, suggesting that HI and RPE could be efficient and more practical to investigate non-functional fatigue during submaximal warm-ups. This information can be used to regulate and adapt the workload during period of training and conditioning to avoid non-functional overreaching or overtraining.