Physical Education Graduate Program, Gama Filho University, Rio de Janeiro, Brazil.
Clinics (Sao Paulo). 2011;66(5):829-35. doi: 10.1590/s1807-59322011000500020.
It is unknown whether an extremely high heart rate can affect oxygen pulse profile during progressive maximal exercise in healthy subjects.
Our aim was to compare relative oxygen pulse (adjusted for body weight) curves in athletes at their maximal heart rate during treadmill cardiopulmonary exercise testing.
A total of 180 elite soccer players were categorized in quartiles according to their maximum heart rate values (n = 45). Oxygen consumption, maximum heart rate and relative oxygen pulse curves in the extreme quartiles, Q1 and Q4, were compared at intervals corresponding to 10% of the total duration of a cardiopulmonary exercise testing.
Oxygen consumption was similar among all subjects during cardiopulmonary exercise testing; however subjects in Q1 started to exhibit lower maximum heart rate values when 20% of the test was complete. Conversely, the relative oxygen pulse was higher in this group when cardiopulmonary exercise testing was 40% complete (p<.01). Although the slopes of the lines were similar (p = .25), the regression intercepts differed (p<.01) between Q1 and Q4. During the last two minutes of testing, a flat or decreasing oxygen pulse was identified in 20% of the soccer players, and this trend was similar between subjects in Q1 and Q4.
Relative oxygen pulse curve slopes, which serve as an indirect and non-invasive surrogate for stroke volume, suggest that the stroke volume is similar in young and aerobically fit subjects regardless of the maximum heart rate reached.
在健康受试者进行渐进性最大运动时，极高的心率是否会影响氧脉搏谱尚不清楚。
我们的目的是比较在跑步机心肺运动测试中达到最大心率时运动员的相对氧脉搏（按体重调整）曲线。
根据最大心率值（n = 45），将 180 名精英足球运动员分为四组。在心肺运动测试总持续时间的 10%对应的间隔处比较 Q1 和 Q4 这两个极值四分位数的耗氧量、最大心率和相对氧脉搏曲线。
在心肺运动测试过程中，所有受试者的耗氧量相似；然而，当测试完成 20%时，Q1 组的最大心率值开始显示出较低的值。相反，在这个组中，当心肺运动测试完成 40%时，相对氧脉搏更高（p<.01）。尽管这些线的斜率相似（p =.25），但 Q1 和 Q4 之间的回归截距不同（p<.01）。在测试的最后两分钟，20%的足球运动员出现了氧脉搏平坦或下降的趋势，而 Q1 和 Q4 组之间的这种趋势相似。
相对氧脉搏曲线斜率可作为每搏输出量的间接、非侵入性替代指标，表明在达到最大心率时，年轻和有氧适能良好的受试者的每搏输出量相似。
