The Acute Physiological and Perceptual Effects of Individualizing the Recovery Interval Duration Based Upon the Resolution of Muscle Oxygen Consumption During Cycling Exercise

Purpose: There has been paucity in research investigating the individualization of recovery interval duration during cycling-based high-intensity interval training (HIIT). The main aim of the study was to investigate whether individualizing the duration of the recovery interval based upon the resolution of muscle oxygen consumption would improve the performance during work intervals and the acute physiological response of the HIIT session, when compared with a standardized (2:1 work recovery ratio) approach. Methods: A total of 16 well-trained cyclists (maximal oxygen consumption: 60 [7] mL·kg−1·min−1) completed 6 laboratory visits: (Visit 1) incremental exercise test, (Visit 2) determination of the individualized (IND) recovery duration, using the individuals’ muscle oxygen consumption recovery duration to baseline from a 4- and 8-minute work interval, (Visits 3–6) participants completed a 6 × 4- and a 3 × 8-minute HIIT session twice, using the IND and standardized recovery intervals. Results: Recovery duration had no effect on the percentage of the work intervals spent at >90% and >95% of maximal oxygen consumption, maximal minute power output, and maximal heart rate, during the 6 × 4- and 3 × 8-minute HIIT sessions. Recovery duration had no effect on mean work interval power output, heart rate, oxygen consumption, blood lactate, and rating of perceived exertion. There were no differences in reported session RPE between recovery durations for the 6 × 4- and 3 × 8-minute HIIT sessions. Conclusion: Individualizing HIIT recovery duration based upon the resolution of muscle oxygen consumption to baseline levels does not improve the performance of the work intervals or the acute physiological response of the HIIT session, when compared with standardized recovery duration.