Physical Activity and Health Promotion Laboratory - LABSAU, Physical Education and Sports Institute, State University of Rio de Janeiro - UERJ, Maracanã, Rio de Janeiro, Brazil.
Eur J Appl Physiol. 2009 Dec;107(6):625-31. doi: 10.1007/s00421-009-1162-y. Epub 2009 Aug 27.
This study investigated the relationship between oxygen uptake (VO(2)), cardiac output (Q), stroke volume (SV), and heart rate (HR) in 54 men and 77 women (age = 69 +/- 5 years) during incremental effort. Subjects performed a maximal cycle-ergometer test and VO(2) was directly measured. HR and SV were assessed by ECG and cardiograph impedance. Regression equations were calculated for Q-VO(2), HR-VO(2), and Q-HR relationships. The equations obtained for women were (a) Q (l min(-1)) = 2.61 + 4.67 VO(2) (l min(-1))(r(2) = 0.84); (b) HR (bpm) = 62.03 + 46.55 VO(2) (l min(-1)) (r (2) = 0.72); (c) SV (ml) 100:6[1 - e(-2.6 VO2 (1 min-1))] (r (2) = 0.41); (d) HR (bpm) = 41.48 + 9.24 Q (l min(-1)) (r (2) = 0.73). Equations for men were (a) Q (l min(-1)) = 2.52 + 5.70 VO(2) (l min(-1)) (r (2) = 0.89); (b) HR (bpm) = 66.31 + 32.35 VO(2) (l min(-1)) (r (2) = 0.72); (c) [1 - e(-1.7 VO2 (1 min-1))] (r (2) = 0.47); (d) HR (bpm) = 56.33 + 5.25 Q (l min(-1)) (r (2) = 0.69). The intercepts for Q-VO(2) and HR-VO(2) equations were similar for both genders, but the slopes were different (P < 0.05). The SV increased from baseline to 50-60% of VO(2) peak in both groups. No gender effect was found in SV increasing pattern, but the absolute values were in general higher for men (P > 0.05). A significant difference between men and women was observed for both slopes and intercepts in the Q-HR relationship (P < 0.05). In conclusion, (a) Q-VO(2) relation was linear during progressive effort; (b) regression intercepts were similar, but the slopes were higher for men compared to women; (c) SV-VO(2) relationship was nonlinear and maximum SV was reached at very submaximal workload; (d) older men exhibited higher Q upward potential as well higher SV but lower HR for a given submaximal workload than women of similar age.
本研究旨在探讨 54 名男性和 77 名女性（年龄=69±5 岁）在递增负荷过程中摄氧量（VO2）、心输出量（Q）、每搏量（SV）和心率（HR）之间的关系。受试者进行了最大的踏车测力计测试，直接测量 VO2。HR 和 SV 通过心电图和心电导联阻抗进行评估。计算了 Q-VO2、HR-VO2 和 Q-HR 关系的回归方程。为女性获得的方程为：（a）Q（升/分钟）= 2.61+4.67 VO2（升/分钟）（r2=0.84）；（b）HR（bpm）= 62.03+46.55 VO2（升/分钟）（r2=0.72）；（c）SV（ml）100:6[1-e(-2.6 VO2（1 分钟-1）)]（r2=0.41）；（d）HR（bpm）= 41.48+9.24 Q（升/分钟）（r2=0.73）。男性的方程为：（a）Q（升/分钟）= 2.52+5.70 VO2（升/分钟）（r2=0.89）；（b）HR（bpm）= 66.31+32.35 VO2（升/分钟）（r2=0.72）；（c）[1-e(-1.7 VO2（1 分钟-1）)]（r2=0.47）；（d）HR（bpm）= 56.33+5.25 Q（升/分钟）（r2=0.69）。两性的 Q-VO2 和 HR-VO2 方程的截距相似，但斜率不同（P<0.05）。两组在 SV 均从基线增加到 VO2 峰值的 50-60%。在 SV 增加模式中没有发现性别效应，但男性的绝对值普遍较高（P>0.05）。男性和女性的 Q-HR 关系中的斜率和截距都存在显著差异（P<0.05）。总之，（a）在渐进性工作中，Q-VO2 关系是线性的；（b）回归截距相似，但男性的斜率高于女性；（c）SV-VO2 关系是非线性的，最大 SV 出现在非常次最大的工作负荷下；（d）年龄较大的男性在给定的次最大工作负荷下，比年龄相似的女性具有更高的 Q 上升潜力、更高的 SV 和更低的 HR。
