Abstract
This study investigated the physiological difference in recreational runners between a noncontinuous and a continuous endurance training protocol. It also aimed to determine physiological surrogate that could monitor metabolic demand of prolonged running in real‐time. For data collection, a total of 18 active male recreational runners were recruited. Physiological (HR, RR, RER, ṼO2, BLa), and overall perceptual (RPEO) responses were recorded against three designed test sessions. Session 1 included ṼO2submax test to determine critical speed (CS) at anaerobic threshold (AT). Session 2 was the noncontinuous CS test until exhaustion, having 4:1 min work‐to‐rest ratio at CS, whereas session 3 was the continuous CS test till exhaustion. As 1‐min recovery during session 2 may change fatigue behavior, it was hypothesized that it will significantly change the physiological stress and hence endurance outcomes. Results reported average time to exhaustion (TTE) was 37.33(9.8) mins for session 2 and 23.28(9.87) mins for session 3. Participants experienced relatively higher metabolic demand (BLa) 6.78(1.43) mmol.l−1 in session 3 as compared to session 2 (5.52(0.93) mmol.l−1). RER was observed to increase in session 3 and decrease in session 2. Student's paired t‐test only reported a significant difference in TTE, ṼO2, RER, RPEO, and BLa at “End” between session 2 and 3. Reported difference in RPEO and %HR max at “AT” were 5 (2.2) and 89.8 (2.60)% during session 2 and 6 (2.5) and 89.8 (2.59)% during session 3, respectively. Regression analysis reported strong correlation of %HR max (adj. R‐square = 0.588) with BLa than RPEO (adj. R‐square = 0.541). The summary of findings suggests that decreasing RER increased TTE and reduced BLa toward “End” during session 2 which might have helped to have better endurance. The %HR max was identified to be used as a better noninvasive surrogate of endurance intensity estimator.
Highlights
During exercise, the cardiorespiratory system is subject to supply a continuous flow of oxygen and nutrients to the skeletal muscles and to remove metabolic products for cellular respiration (Myers 2001; Crisp et al 2013)
Considering the physiological over studied variables between session 2 and 3, this study suggests that time to exhaustion (TTE) may subject to opposing trend in respiratory exchange ratio (RER), reduced running economy, increased RPEO and BLa
The results of present study establish that critical speed (CS) was associated with maximum lactate steady state (MLSS) during the noncontinuous test whereas continuous test overestimated the MLSS
Summary
The cardiorespiratory system is subject to supply a continuous flow of oxygen and nutrients to the skeletal muscles and to remove metabolic products for cellular respiration (Myers 2001; Crisp et al 2013). The physiological response is dependent on the running speed. Literature has reported a strong correlation (0.68–0.98) of endurance pace with critical speed (CS) at anaerobic threshold (AT = blood lactate of 4.0 mmol.LÀ1) over the long-distance competitions (Faude et al 2009). Sports scientists have proposed various methods to determine CS that could best represent the optimal endurance speed. Some reported methods include linear regression of distance versus time, the speed at anaerobic threshold and associated maximum lactate steady state (MLSS) speed (Kranenburg and Smith 1996; Smith and Jones 2001; Bull et al 2008). The critical speed (CS) was selected in this research, considering the fact that treadmill CS a 2017 The Authors.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
