Lai Nicola, Martis Alessandro, Belfiori Alfredo, Tolentino-Silva Fatima, Nasca Melita M, Strainic James, Cabrera Marco E
Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio Department of Pediatrics Cardiology, Case Western Reserve University, Cleveland, Ohio Center for Modeling Integrated Metabolic Systems, Cleveland, Ohio Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia Biomedical Engineering Institute, Old Dominion University, Norfolk, Virginia
Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio.
Physiol Rep. 2016 Sep;4(18). doi: 10.14814/phy2.12970.
The majority of the studies on V˙O2 kinetics in pediatric populations investigated gender differences in prepubertal children during submaximal intensity exercise, but studies are lacking in adolescents. The purpose of this study was to test the hypothesis that gender differences exist in the V˙O2 and heart rate (HR) kinetic responses to moderate (M) and heavy (H) intensity exercise in adolescents. Twenty-one healthy African-American adolescents (9 males, 15.8 ± 1.1 year; 12 females, 15.7 ± 1 year) performed constant work load exercise on a cycle ergometer at M and H. The V˙O2 kinetics of the male group was previously analyzed (Lai et al., Appl. Physiol. Nutr. Metab. 33:107-117, 2008b). For both genders, V˙O2 and HR kinetics were described with a single exponential at M and a double exponential at H. The fundamental time constant (τ) of V˙O2 was significantly higher in female than male at M (45 ± 7 vs. 36 ± 11 sec, P < 0.01) and H (41 ± 8 vs. 29 ± 9 sec, P < 0.01), respectively. The functional gain (G) was not statistically different between gender at M and statistically higher in females than males at H: 9.7 ± 1.2 versus 10.9 ± 1.3 mL min W, respectively. The amplitude of the slow component was not significantly different between genders. The HR kinetics were significantly (τ, P < 0.01) slower in females than males at M (61 ± 16 sec vs. 45 ± 20 sec, P < 0.01) and H (42 ± 10 sec vs. 30 ± 8 sec, P = 0.03). The G of HR was higher in females than males at M: 0.53 ± 0.11 versus 0.98 ± 0.2 bpm W and H: 0.40 ± 0.11 versus 0.73 ± 0.23 bpm W, respectively. Gender differences in the V˙O2 and HR kinetics suggest that oxygen delivery and utilization kinetics of female adolescents differ from those in male adolescents.
大多数关于儿童群体中摄氧量动力学的研究调查了青春期前儿童在次最大强度运动期间的性别差异，但针对青少年的研究尚缺。本研究的目的是检验以下假设：青少年在中等强度（M）和高强度（H）运动时，摄氧量（V˙O₂）和心率（HR）的动力学反应存在性别差异。21名健康的非裔美国青少年（9名男性，年龄15.8 ± 1.1岁；12名女性，年龄15.7 ± 1岁）在功率自行车上进行M强度和H强度的恒定负荷运动。男性组的V˙O₂动力学此前已进行分析（Lai等人，《应用生理学、营养与代谢》33:107 - 117，2008b）。对于男女两性，M强度时V˙O₂和HR动力学用单指数描述，H强度时用双指数描述。在M强度（45 ± 7秒 vs. 36 ± 11秒，P < 0.01）和H强度（41 ± 8秒 vs. 29 ± 9秒，P < 0.01）下，女性V˙O₂的基本时间常数（τ）显著高于男性。在M强度时，功能增益（G）在性别间无统计学差异，在H强度时女性的G在统计学上高于男性：分别为9.7 ± 1.2与10.9 ± 1.3 mL·min⁻¹·W⁻¹。慢成分的幅度在性别间无显著差异。在M强度（61 ± 16秒 vs. 45 ± 20秒，P < 0.01）和H强度（42 ± 10秒 vs. 30 ± 8秒，P = 0.
