Research Group in Sports Biomechanics (GIBD), Department of Physical Education and Sports, Universitat de València, Valencia, Spain.
Red Española de Investigación del Rendimiento Deportivo en Ciclismo y Mujer (REDICYM), Consejo Superior de Deportes (CSD), Madrid, Spain.
J Appl Physiol (1985). 2023 Nov 1;135(5):1092-1101. doi: 10.1152/japplphysiol.00420.2023. Epub 2023 Sep 21.
Although in recent years near-infrared spectroscopy has been used in many sports to monitor muscle oxygen saturation (SmO), there is a lack of knowledge about the sex differences in SmO during exercise in different muscles. Our study aimed to examine SmO differences in muscles between female and male cyclists, during a graded cycling test and at the first and second lactate thresholds. Twenty-five trained cyclists and triathletes (15 males: 23 ± 7 yr, 1.78 ± 0.05 m, 70.2 ± 5.3 kg, and 10 females: 22 ± 5 yr, 1.64 ± 0.06 m, 58 ± 8 kg) performed a graded cycling test on the cycle ergometer. Power output and SmO in five muscles (dominant vastus lateralis, tibialis anterior, gastrocnemius medial, biceps femoris, and triceps brachii) were measured. Our mixed regression models showed that the interaction between power output and sex was significant for all the muscles analyzed ( < 0.001), indicating a greater decrease in SmO for males as power output increased. Moreover, the statistical parametric mapping analyses showed for females higher SmO in the middle of the test in biceps femoris ( = 0.03), gastrocnemius medial ( = 0.02), and tibialis anterior ( = 0.04). Finally, the males presented a lower SmO in all muscles where the second lactate threshold occurred, with greater evidence than in the first lactate threshold. In conclusion, females have higher SmO in all muscles, and these differences are more noticeable during the graded cycling test, such that males seem to have a greater reliance on oxygen extraction than females for a given relative intensity of exercise. This study investigated the profiles of muscle oxygen saturation (SmO) during incremental exercise in females and males. Females presented higher overall SmO than males during moderate and heavy intensity domain exercise in all muscles including muscles that are not mainly involved in pedaling (triceps brachii), from those that are stabilizers (medial gastrocnemius, tibialis anterior, and biceps femoris), to those that are related to power output production (vastus lateralis).
尽管近年来近红外光谱技术已被广泛应用于多项运动中以监测肌肉氧饱和度（SmO），但关于不同肌肉在运动中 SmO 的性别差异，我们的知识还很有限。我们的研究旨在比较女性和男性自行车运动员在递增负荷运动测试及第一和第二乳酸阈时不同肌肉的 SmO 差异。25 名有训练经验的自行车运动员和三项全能运动员（男性 15 名：23 ± 7 岁，1.78 ± 0.05 米，70.2 ± 5.3 千克；女性 10 名：22 ± 5 岁，1.64 ± 0.06 米，58 ± 8 千克）在功率自行车上进行递增负荷运动测试。测量了 5 块肌肉（优势股外侧肌、胫骨前肌、腓肠肌内侧、股二头肌和肱三头肌）的功率输出和 SmO。我们的混合回归模型显示，在分析的所有肌肉中，功率输出与性别的相互作用均具有统计学意义（ < 0.001），这表明随着功率输出的增加，男性的 SmO 下降幅度更大。此外，统计参数映射分析显示，女性在测试中段时，股二头肌（ = 0.03）、腓肠肌内侧（ = 0.02）和胫骨前肌（ = 0.04）的 SmO 更高。最后，男性在出现第二乳酸阈的所有肌肉中的 SmO 均较低，而且在第二乳酸阈时比在第一乳酸阈时更为明显。总之，女性在所有肌肉中的 SmO 均较高，而且在递增负荷运动测试中，这些差异更为明显，这表明在给定的相对运动强度下，男性似乎比女性更依赖于氧摄取。本研究调查了女性和男性在递增运动时肌肉氧饱和度（SmO）的变化特征。在所有肌肉中，包括那些不主要参与踩踏的肌肉（肱三头肌）、稳定器（腓肠肌内侧、胫骨前肌和股二头肌）以及与功率输出产生相关的肌肉（股外侧肌），女性在中高强度运动域的整体 SmO 均高于男性。
