Reliability of Low-Cost Near-Infrared Spectroscopy in the Determination of Muscular Oxygen Saturation and Hemoglobin Concentration during Rest, Isometric and Dynamic Strength Activity

Abstract

Background: The objective of this study was to establish the reliability of the Humon Hex near-infrared reflectance spectroscopy (NIRS) in determining muscle oxygen saturation (SmO2) and hemoglobin concentration (Hgb) at rest and during isometric and dynamic strength exercises using a functional electromechanical dynamometer (FEMD). Methods: The SmO2 and Hgb values of sixteen healthy adults (mean ± standard deviation (SD): Age = 36.1 ± 6.4 years) were recorded at rest and during isometry (8 s), dynamic strength I (initial load of 40% of the average isometric load, with 2 kg increments until muscle failure) and dynamic strength II (same as I, but with an initial load of 40% of the maximum isometric load) activity. To evaluate the reliability in the determination of SmO2 and Hgb of this device, intraclass correlation coefficient (ICC), standard error of measurement (SEM) and coefficient of variation (CV) were obtained. Results: The main results obtained are SmO2 at rest (CV = 5.76%, SEM = 3.81, ICC = 0.90), isometric strength (CV = 3.03%, SEM = 2.08, ICC = 0.92), dynamic strength I (CV = 10.6, SEM = 7.17, ICC = 0.22) and dynamic strength II (CV = 9.69, SEM = 6.75, ICC = 0.32); Hgb at rest (CV = 1.97%, SEM = 0.24, ICC = 0.65), isometric strength (CV = 0.98%, SEM = 0.12, ICC = 0.96), dynamic strength I (CV = 3.25, SEM = 0.40, ICC = 0.54) and dynamic strength II (CV = 2.74, SEM = 0.34, ICC = 0.65). Conclusions: The study shows that Humon Hex is a reliable device to obtain SmO2 and Hgb data in healthy adult subjects at rest and during isometric strength, providing precision for measurements made with this device.

Changes in Muscle Oxygen Saturation Measured Using Wireless Near-Infrared Spectroscopy in Resistance Training: A Systematic Review

“…Today, near-infrared spectroscopy (NIRS) has positioned itself in the field of physical activity and health as a valid, reliable and inexpensive wireless instrument [1][2][3][4][5][6][7]. In addition, this technology is capable of evaluating, in real time, the balance between muscle oxygen supply and its demand during physical exercise [8].…”

Test–retest reliability of skeletal muscle oxygenation measurement using near‐infrared spectroscopy during exercise in patients with sport‐related iliac artery flow limitation

“…By contrast, most recovery kinetic ( , MRT and HVT) variables showed fair to good absolute reliability yet good to almost perfect relative reliability with statistically significant differences in the responses of recovery kinetics after exercise between FLIA patients having predominantly subtle flow limitations and healthy subjects. Other studies showed that absolute values, amplitude and reoxygenation kinetics showed poor to near excellent relative reliability in varying populations and exercise types (Baláš et al, 2018 ; Buchheit et al, 2011 ; Cayot et al, 2021 ; Choo et al, 2016 ; Contreras‐Briceño et al, 2019 ; Crenshaw et al, 2012 ; Ihsan et al, 2013 ; Leclair et al, 2010 ; Lucero et al, 2018 ; McManus et al, 2018 ; Miranda‐Fuentes et al, 2020 ; Muthalib et al, 2010 ; Niemeijer et al, 2017 ; Pocivalnik et al, 2011 ; Thiel et al, 2011 ; Ubbink & Koopman, 2006 ). Given the combination of good to almost perfect relative reliability and significant differences in reoxygenation variables, results suggest that NIRS recovery kinetics (MRT and HVT) may be useful and may prove superior to ABI flexed when diagnosing sport‐related flow limitations in the iliac arteries.…”

“…Our resting period for baseline assessment consisted of 1 min seated on the bike without restrictions on pedal position. Other studies used different techniques or muscles (e.g., multiple sensors, upper extremities) with a large range of ICC (0.42–0.95) and CV (2%–8%) (Baláš et al, 2018 ; Contreras‐Briceño et al, 2019 ; Crenshaw et al, 2012 ; Miranda‐Fuentes et al, 2020 ; Muthalib et al, 2010 ; Ubbink & Koopman, 2006 ).…”

Test–Retest Reliability of Functional Electromechanical Dynamometer on Five Sit-to-Stand Measures in Healthy Young Adults

“…Currently, the development of the functional electromechanical dynamometer (FEMD) (as opposed to the angular isokinetic devices) [ 28 ] allows systematizing and controlling multiple components of the load during the performance of natural movements, such as the range and velocity of movement, magnitude of resistance, control of strength exercised and type of muscle contraction (isometric, concentric and eccentric). In this regard, studies have assessed the reliability and validity [ 29 , 30 , 31 , 32 ] and used the FEMD [ 33 , 34 , 35 , 36 , 37 , 38 ] under different experimental modalities and muscle groups. However, studies that propose to assess the reliability of the STS test using this type of technology have not been previously developed.…”