Functional Neuroimaging Group, Department of Radiology, University Hospital Bonn, Bonn, Germany.
DZNE, German Center for Neurodegenerative Diseases, Bonn, Germany.
Eur J Pain. 2020 Mar;24(3):568-579. doi: 10.1002/ejp.1508. Epub 2019 Dec 6.
The phenomenon of exercise-induced hypoalgesia and concomitant mood changes is well-established. How exercise-induced hypoalgesia and affective responses are shaped by the intensity of an acute exercise bout and individual fitness levels is as yet not well-understood. This study investigates whether heat pain threshold (PTh), pain tolerance (PTol) and affective parameters are modulated by the intensity of an acute exercise bout and/or individuals' fitness level. Stronger analgesic responses are hypothesized after high-intensity exercise in physically fitter subjects, possibly in sync with concomitant mood changes.
Thirty-three healthy men were recruited (sedentary: N = 17 or recreational: N = 14; mean age: 25.3 ± 4.4 years). After a fitness assessment on a cycle ergometer, subjects underwent three experimental conditions on separate days: high (20 min exercise 20% above lactate threshold), low (20 min exercise 20% below lactate threshold) and control (seated rest). Before and after each intervention Positive and Negative Affect Schedule, PTh and PTol (cold water emersion test) were assessed.
Results indicate an increase of the Positive Affect Scale (high: 26.7 ± 9.0 vs. 32.9 ± 7.1, p < .001; low: 26.3 ± 7.2 vs. 32.0 ± 7.0, p < .001) and PTh (high: 45.1 ± 3.1°C vs. 46.0 ± 2.6°C, p = .003; low: 45.4 ± 2.7°C vs. 45.9 ± 2.6°C, p = .012) after both exercise conditions. In an exploratory analysis, PTol significantly increased only after the high exercise condition (51.2 ± 33.7 s vs. 72.4 ± 64.0 s, p = .045). Fitness level was positively correlated with the increase in PTol from pre to post high-intensity exercise (r = .59, p (one-tailed) = .002).
Exercise-induced hypoalgesia depends on exercise intensity and appears to be influenced by individual fitness status, independent of mood responses.
Antinociceptive effects can be elicited by physical exercise and have been extensively investigated in the literature. However, the relation between exercise intensity, fitness status, and the degree of antinociception is not well-understood. This randomized intervention provides novel evidence that antinociceptive effects indeed depend on exercise intensity, but also on general fitness status. Data extend the existing literature by highlighting aspects of exercise behaviour that promote antinociception. Effects do not simply mirror positive affective responses induced by exercise, hence, indicating partially distinct underlying mechanisms.
运动诱导的痛觉减退和伴随的情绪变化是众所周知的现象。运动诱导的痛觉减退和情感反应如何受到急性运动强度和个体健康水平的影响还不太清楚。本研究调查了热痛阈（PTh）、疼痛耐受（PTol）和情感参数是否受急性运动强度和/或个体健康水平的调节。在身体更健康的受试者中，高强度运动后可能会产生更强的镇痛反应，可能与伴随的情绪变化同步。
招募了 33 名健康男性（久坐：N=17 或娱乐：N=14；平均年龄：25.3±4.4 岁）。在进行了自行车测力计的体能评估后，受试者在 3 个不同的日子分别接受了 3 种实验条件：高（20 分钟运动，高于乳酸阈值 20%）、低（20 分钟运动，低于乳酸阈值 20%）和对照（静坐休息）。在每次干预前后，均评估正性和负性情感量表、PTh 和 PTol（冷水浸出试验）。
结果表明，积极情感量表（高：26.7±9.0 对 32.9±7.1，p<0.001；低：26.3±7.2 对 32.0±7.0，p<0.001）和 PTh（高：45.1±3.1°C 对 46.0±2.6°C，p=0.003；低：45.4±2.7°C 对 45.9±2.6°C，p=0.012）在两种运动条件后均有所增加。在一项探索性分析中，仅在高强度运动后，PTol 显著增加（51.2±33.7 s 对 72.4±64.0 s，p=0.045）。体能水平与高强度运动前后 PTol 的增加呈正相关（r=0.59，p（单侧）=0.002）。
运动诱导的痛觉减退取决于运动强度，并且似乎受到个体健康状况的影响，而与情绪反应无关。
身体运动可以产生镇痛作用，这在文献中已经得到了广泛的研究。然而，运动强度、健康状况和镇痛程度之间的关系还不太清楚。这项随机干预提供了新的证据，表明镇痛作用确实取决于运动强度，但也取决于一般的健康状况。数据通过突出促进镇痛的运动行为方面，扩展了现有文献。这些作用并不简单地反映运动引起的积极情感反应，因此，表明存在部分不同的潜在机制。
