Abstract
Introduction: The purpose was to quantify the within-session and between-session reliability of halftime (HT) and monoexponential curve fitting (EXP) analyses, when assessing the microvascular tissue oxygenation (StO2) recovery response via near-infrared spectroscopy (NIRS). Methods: Seventeen subjects completed a submaximal cycling test and 6-minute cool-down on three occasions. The protocol was completed twice during session 1 and once during session 2. StO2 were collected via NIRS from a randomized vastus lateralis. StO2 response from the last minute of exercise and the entire cool-down was analyzed using HT and EXP. Within-session and between-session reliability were examined by mixed, absolute agreement intraclass correlation coefficients (ICC) and standard error of the measurement (SEM). Results: HT resulted in higher within-session reliability compared to EXP for exercising StO2 (ICCHT=0.920, ICCEXP=0.865, SEMHT=4.9 ∆BSL, SEMEXP=6.2 ∆BSL) and StO2 recovery time (ICCHT=0.772, ICCEXP=0.720, SEMHT=7 sec, SEMEXP=9 sec). Similar between-session reliability for exercising StO2 was observed (ICCHT=0.895, ICCEXP=0.879, SEMHT=5.2 ∆BSL, SEMEXP=5.4 ∆BSL), however HT elicited higher between-session reliability for StO2 recovery time (ICCHT=0.583, ICCEXP=-0.211, SEMHT=7 sec, SEMEXP=15 sec). Conclusions: Due to the better within-session (exercising StO2, StO2 recovery time) and between-session (StO2 recovery time) reliability, practitioners are encouraged to use HT when assessing exercising StO2 and StO2 recovery time.
Highlights
The purpose was to quantify the within-session and between-session reliability of halftime (HT) and monoexponential curve fitting (EXP) analyses, when assessing the microvascular tissue oxygenation (StO2) recovery response via nearinfrared spectroscopy (NIRS)
Since decreased PCr concentrations have been associated with increased mitochondrial respiration, an exercise bout which decreases the PCr/creatine ratio will promote PCr resynthesis[1], potentially aiding in sustained performance during subsequent exercise[2]
Creatine can be rephosphorylated via a creatine shuttling mechanism within the inner mitochondrial membrane and the resulting PCr is transferred to the cytosol via a voltage-dependent anion channel[3,4]
Summary
The purpose was to quantify the within-session and between-session reliability of halftime (HT) and monoexponential curve fitting (EXP) analyses, when assessing the microvascular tissue oxygenation (StO2) recovery response via nearinfrared spectroscopy (NIRS). Results: HT resulted in higher within-session reliability compared to EXP for exercising StO2 (ICCHT=0.920, ICCEXP=0.865, SEMHT=4.9 ∆BSL, SEMEXP=6.2 ∆BSL) and StO2 recovery time (ICCHT=0.772, ICCEXP=0.720, SEMHT=7 sec, SEMEXP=9 sec). Since the creatine shuttling mechanism is ATP dependent, requiring oxygen uptake, many studies have investigated the microvascular tissue oxygenation (StO2) response during (exercising StO2) and immediately following (StO2 recovery time) an exercise bout using near-infrared spectroscopy (NIRS)[2,5,6,7]. The faster StO2 recovery time has been associated with PCr resynthesis rates[7], maximal aerobic speed[2], the ability to sustain high intensity efforts during multiple exercise bouts[2], and being a non-invasive indicator of skeletal muscle oxidative capacity[8]
Sign-in/Register to view highlights & summary 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.
