Reliability and reproducibility of a four arterial occlusions protocol for assessing muscle oxidative metabolism at rest and after exercise using near-infrared spectroscopy

Abstract

Objective: To assess the reliability and reproducibility of using a four arterial occlusions protocol and near-infrared spectroscopy (NIRS) to measure resting and post-exercise muscle oxidative metabolism (mVO2). Approach: mVO2 was measured on the forearm muscles on two different days (day1 and day2) within one week in 11 healthy young adults (24.2 ± 2.7 years; 5 males). mVO2 was measured using NIRS during four repeated arterial occlusions at rest, and 5 min after exercise consisting of 90 s of rapid concentric contractions (5 minEPOC). Main results: Resting mVO2 with four measurements was 17.88 ± 3.04% min−1 on day 1 and 19.42 ± 3.03% min−1 on day 2 (p = 0.171) with a coefficient of variation (CV) of 10.1%. When using only the first measurement, the CV increased to 18.5% (p = 0.039). 5minEPOC was 212.4 ± 142.5% and 177.1 ± 125.8% higher than resting and was not different between days one and two (53.83 ± 21.17% min−1 and 52.22 ± 22.10% min−1, respectively, p= 0.199). The CV and intraclass correlation (ICC) for 5minEPOC between days one and two were, 6.5% and 0.98, respectively. Using only the first value for 5minEPOC resulted in slightly higher CV but similar ICC (7.6% and 0.98, respectively; both p > 0.05). Significance: Our results suggest that within a single testing session, one arterial occlusion can provide reproducible measurements for both resting and post-exercise mVO2 similar to that of a four arterial occlusions protocol. While a four arterial occlusion protocol provides similar reliability for post-exercise mVO2 with one arterial occlusion, it reduces the day-to-day variance for resting mVO2 and therefore should be employed for longitudinal studies.

Measuring tibial hemodynamics and metabolism at rest and after exercise using near-infrared spectroscopy

“…For MG muscle the longest separation distance (4 cm) was used, which gave a mean penetration depth of approximately 2 cm. The choice of different separation distances is consistent with previous studies, which generally choose long separation distances (or channels) for muscle, but short separation distances for bone (Draghici et al, 2018, Zhang et al, 2020, Malagoni et al, 2013, Binzoni et al, 2006. The longer separation distance for muscle is in part due to the greater amount of ATT over the muscle compared to the tibial bone.…”

“…Metabolic rate for the tibia was measured during occlusion in a method analogous to the method for measuring muscle metabolic rate with NIRS (Zhang et al, 2020). Due to the irregular signal shape of HbO 2 and HbDiff after exercise (Figure 1B), it was only possible to consistently determine HHb signal rate of change during occlusion.…”

Men exhibit faster skeletal muscle tissue desaturation than women before and after a fatiguing handgrip

“…A strength of the current experimental design was that it permitted the determination of test–retest reliability given VOTs were performed in a rested, pre-exercise state during the familiarization and experimental visits. Previous investigations have reported NIRS-related ICCs ranging from 0.26 to 0.98 (Ryan et al 2012 ; Southern et al 2013 ; McLay et al 2016 ; Iannetta et al 2019 ; Zhang et al 2020 ), yet there are currently no known studies that have examined the reliability of young, healthy males and females. Our measurement of the rate of early phase StO 2 desaturation presented a strong ICC 2,1 , which supports that the observed differences were likely due to sex and/or fatigue, not systematic error.…”

“…Simple linear regression was used to examine the rate of desaturation across Time. The slopes of the males and females resulting from the simple linear analyses were tested for mean differences (Zar 2017;Chapt 18). During sustained tasks, StO 2 generally presents a biphasic response across time, thus rendering linear regression inappropriate.…”

The Case for Measuring Long Bone Hemodynamics With Near-Infrared Spectroscopy

“…The application of NIRS to assess bone hemodynamics and oxygenation might be expected to be based on the rather extensive literature on the use of NIRS to study skeletal muscle in both healthy (van Beekvelt et al, 2001a,b;Ryan et al, 2013a,b;Southern et al, 2014;Zhang et al, 2020) as well as in clinical populations (Abozguia et al, 2008;Sjogaard et al, 2010;Bossie et al, 2017;Willingham et al, 2019). NIRS measurements of skeletal muscle can mainly be divided into three categories: (1) measuring levels of oxygen at rest and during exercise (Hesford et al, 2013;Niemeijer et al, 2017), (2) measuring the rate of re-oxygenation after ischemia or exercise (Willingham et al, 2016;Willingham and McCully, 2017;Lucero et al, 2018), and finally (3) using short periods of repeated ischemia to measure oxidative metabolism or mitochondrial capacity (Ryan et al, 2013b;Bossie et al, 2017;Sumner et al, 2020).…”