Thomaes Tom, Thomis Martine, Onkelinx Steven, Goetschalckx Kaatje, Fagard Robert, Cornelissen Véronique, Vanhees Luc
Research Group for Cardiovascular and Respiratory Rehabilitation, Department of Rehabilitation Sciences, KULeuven, Leuven, Belgium.
Acta Cardiol. 2012 Aug;67(4):399-406. doi: 10.1080/ac.67.4.2170680.
Low exercise capacity and skeletal muscle strength are important predictors of all-cause mortality in healthy as well as diseased individuals. Compared to sedentary subjects, CAD patients have a decreased oxygen uptake (peakVO2) and show accompanying increased muscle fatiguability. Despite the known importance of oxygen extraction by peripheral muscles on improving peakVO2 and of the relationship between muscle strength and aerobic capacity, only few studies in CAD patients include measurements of muscle strength before and after cardiac rehabilitation. This study therefore aimed to evaluate how much of the variance in baseline peakVO2 and its response to exercise training can be explained by muscular parameters.
260 CAD patients performed maximal incremental cycle ergometer testing and maximal knee muscle strength measurements. The rectus femoris diameter was measured using ultrasound. Zero order correlations were calculated and determinants of baseline and response in peakVO2 were analysed by multiple regression analysis.
PeakVO2 and muscle strength and diameter increased significantly after three months of cardiac rehabilitation (P < 0.0001). Zero order correlations showed significant correlations between muscular parameters and baseline peakVO2 (P < 0.0001). 63% of the total variance in baseline peakVO2 could be explained by seven parameters with knee extensor muscular endurance as the strongest predictor (P < 0.0001). 32% of the variation in relative increase in peakVO2 could be explained by 5 determinants of which the increase in muscular endurance was the strongest determinant (P < 0.0001).
Knee extensor muscular endurance and its response after training are the strongest muscular predictors in explaining peakVO2 and its response in CAD patients.
运动能力低下和骨骼肌力量是健康个体以及患病个体全因死亡率的重要预测指标。与久坐不动的受试者相比，冠心病患者的摄氧量（峰值VO2）降低，且伴随肌肉疲劳性增加。尽管外周肌肉的氧摄取对提高峰值VO2的重要性以及肌肉力量与有氧能力之间的关系已为人所知，但在冠心病患者中，只有少数研究包括心脏康复前后肌肉力量的测量。因此，本研究旨在评估肌肉参数能在多大程度上解释基线峰值VO2的变化及其对运动训练的反应。
260例冠心病患者进行了最大递增式蹬车测试和最大膝关节肌肉力量测量。使用超声测量股直肌直径。计算零阶相关性，并通过多元回归分析分析峰值VO2的基线和反应的决定因素。
心脏康复三个月后，峰值VO2、肌肉力量和直径显著增加（P < 0.0001）。零阶相关性显示肌肉参数与基线峰值VO2之间存在显著相关性（P < 0.0001）。基线峰值VO2总方差的63%可由七个参数解释，其中膝关节伸肌耐力是最强的预测指标（P < 0.0001）。峰值VO2相对增加量的32%可由五个决定因素解释，其中肌肉耐力的增加是最强的决定因素（P < 0.0001）。
膝关节伸肌耐力及其训练后的反应是解释冠心病患者峰值VO2及其反应的最强肌肉预测指标。
