Lind Erik, Joens-Matre Roxane R, Ekkekakis Panteleimon
Department of Health and Human Performance, Iowa State University, Ames, IA 50011, USA.
Prev Med. 2005 Apr;40(4):407-19. doi: 10.1016/j.ypmed.2004.07.006.
The intensity of physical activity has been found to be inversely related to adherence, thus contributing to the problem of physical inactivity. Although most physical activity is unsupervised and participants, therefore, self-select the intensity, very little is known about the level of intensity that they select. We hypothesized that participants would select, on average, an intensity proximal to the level of transition from aerobic to anaerobic metabolism.
Twenty-three middle-aged, formerly sedentary women participated in (a) an incremental treadmill test to determine their maximal aerobic capacity and gas exchange ventilatory threshold, an index of the aerobic-anaerobic transition, and (b) a 20-min bout of treadmill exercise during which they were allowed to select the speed.
On average, but with considerable interindividual variability, the women selected an intensity that, in terms of treadmill speed, heart rate, oxygen uptake, and perceived exertion was no different from the intensity corresponding to their gas exchange ventilatory threshold. Moreover, affective valence remained positive and stable.
On average, middle-aged, formerly sedentary women selected an intensity that is considered physiologically effective and reported that it did not feel hard or unpleasant. Future research should examine the sources of interindividual variability and the consequences of exercising at an intensity that exceeds one's preferred level.
已发现身体活动强度与依从性呈负相关，从而导致身体不活动问题。尽管大多数身体活动是无监督的，参与者因此自行选择强度，但对于他们所选择的强度水平知之甚少。我们假设参与者平均会选择接近从有氧代谢过渡到无氧代谢水平的强度。
23名中年、以前久坐不动的女性参加了：（a）递增式跑步机测试，以确定她们的最大有氧能力和气体交换通气阈值，这是有氧 - 无氧过渡的一个指标；（b）20分钟的跑步机运动，在此期间她们可以选择速度。
平均而言，但个体间存在相当大的差异，这些女性选择的强度，就跑步机速度、心率、摄氧量和主观用力感觉而言，与对应于她们气体交换通气阈值的强度没有差异。此外，情感效价保持积极且稳定。
平均而言，中年、以前久坐不动的女性选择了一种被认为具有生理效果的强度，并报告说这种强度感觉不累或不难受。未来的研究应探讨个体间差异的来源以及以超过个人偏好水平的强度进行锻炼的后果。
