Reliability of forearm oxygen uptake during handgrip exercise: assessment by ultrasonography and venous blood gas

Abstract

Assessment of forearm oxygen uptake (trueV˙O2) during handgrip exercise is a keenly investigated concept for observing small muscle mass metabolism. Although a combination of Doppler ultrasound measurements of brachial artery blood flow (trueQ˙) and blood gas drawn from a deep forearm vein has been utilized to calculate forearm trueV˙O2 for more than two decades, the applicability of this experimental design may benefit from a thorough evaluation of its reliability during graded exercise. Therefore, we evaluated the reliability of this technique during incremental handgrip exercise in ten healthy young (24 ± 3(SD) years.) males. trueV˙O2 and work rate (WR) exhibited a linear relationship (1.0 W: 43.8 ± 10.1 mL·min−1; 1.5 W: 53.8 ± 14.1 mL·min−1; 2.0 W: 63.4 ± 16.3 mL·min−1; 2.5 W: 72.2 ± 17.6 mL·min−1; 3.0 W: 79.2 ± 18.6 mL·min−1; r = 0.65, P < 0.01). In turn, trueV˙O2 was strongly associated with trueQ˙ (1.0 W: 359 ± 86 mL·min−1; 1.5 W: 431 ± 112 mL·min−1; 2.0 W: 490 ± 123 mL·min−1; 2.5 W: 556 ± 112 mL·min−1; 3.0 W: 622 ± 131 mL·min−1; r = 0.96; P < 0.01), whereas arteriovenous oxygen difference (a‐vO2diff) remained constant following all WRs (123 ± 11–130 ± 10 mL·L−1). Average trueV˙O2 test–retest difference was −0.4 mL·min−1 with ±2SD limits of agreement (LOA) of 8.4 and −9.2 mL·min−1, respectively, whereas coefficients of variation (CVs) ranged from 4–7%. Accordingly, test–retest trueQ˙ difference was 11.9 mL·min−1 (LOA: 84.1 mL·min−1; −60.4 mL·min−1) with CVs between 4 and 7%. Test–retest difference for a‐vO 2diff was −0.28 mL·dL−1 (LOA: 1.26mL·dL −1; −1.82 mL·dL−1) with 3–5% CVs. In conclusion, our results revealed that forearm trueV˙O2 determination by Doppler ultrasound and direct venous sampling is linearly related to WR, and a reliable experimental design across a range of exercise intensities.

Determinants of skeletal muscle oxygen consumption assessed by near-infrared diffuse correlation spectroscopy during incremental handgrip exercise

“…The observed plateau in SV O 2 and the arterial-venous O 2 difference are in line with several recent reports involving handgrip exercise (5,23,24). Yet, this observed plateau is in direct contrast with the DCS-derived tissue-saturation measurement, which showed a linear decline throughout the incremental exercise challenge.…”

Global REACH 2018: the adaptive phenotype to life with chronic mountain sickness and polycythaemia

“…Arterial and venous blood samples were extracted using 10 ml safePICO syringes and immediately analysed via ABL90 FLEX blood gas analyser (Radiometer Medical ApS, Brønshøi, Denmark), to determine arterial (CaO 2 ) and venous (CvO 2 ) oxygen content, using previously described methods (Nyberg et al, 2018). Heart rate was continuously measured via three-lead electrocardiogram (ADInstruments, Sydney, Australia).…”

Assessment of resistance vessel function in human skeletal muscle: guidelines for experimental design, Doppler ultrasound, and pharmacology

“…Regardless of known limb differences, the forearm is often studied for a number of reasons, including 1) isolation of intrinsic mechanisms without influence of central hemodynamics (e.g., cardiac output) (63,90,91), although some would argue that one-legged knee extension exercise also poses minimal cardiopulmonary stress, particularly at submaximal work rates (8, 176 -178, 190, 231); 2) significance of the forearm to activities of daily living (e.g., carrying groceries, opening jars); and 3) relatively easy access to venous and arterial vessels (192). It should be noted that the initial studies using forearm plethysmography were done by clinical pharmacologists.…”

“…Second, following optimization of the image, ultrasound settings such as 2D gain, PW gain, sample volume, and sweep speed should not be altered within a given experiment and should be reproduced between study visits. Furthermore, the preferred approach by several laboratories is to use a sample volume that encompasses the entire width of the vessel (192). However, this is somewhat controversial.…”