Zschucke Elisabeth, Renneberg Babette, Dimeo Fernando, Wüstenberg Torsten, Ströhle Andreas
Jacobs Center on Lifelong Learning and Institutional Development, Jacobs University Bremen, Bremen, Germany; Department of Educational Sciences and Psychology, Freie Universität Berlin, Berlin, Germany; Department of Psychiatry and Psychotherapy, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany.
Department of Educational Sciences and Psychology, Freie Universität Berlin, Berlin, Germany.
Psychoneuroendocrinology. 2015 Jan;51:414-25. doi: 10.1016/j.psyneuen.2014.10.019. Epub 2014 Oct 25.
According to the cross-stressor adaptation hypothesis, physically trained individuals show lower physiological and psychological responses to stressors other than exercise, e.g. psychosocial stress. Reduced stress reactivity may constitute a mechanism of action for the beneficial effects of exercise in maintaining mental health. With regard to neural and psychoneuroendocrine stress responses, the acute stress-buffering effects of exercise have not been investigated yet. A sample of highly trained (HT) and sedentary (SED) young men was randomized to either exercise on a treadmill at moderate intensity (60-70% VO2max; AER) for 30 min, or to perform 30 min of "placebo" exercise (PLAC). 90 min later, an fMRI experiment was conducted using an adapted version of the Montreal Imaging Stress Task (MIST). The subjective and psychoneuroendocrine (cortisol and α-amylase) changes induced by the exercise intervention and the MIST were assessed, as well as neural activations during the MIST. Finally, associations between the different stress responses were analysed. Participants of the AER group showed a significantly reduced cortisol response to the MIST, which was inversely related to the previous exercise-induced α-amylase and cortisol fluctuations. With regard to the sustained BOLD signal, we found higher bilateral hippocampus (Hipp) activity and lower prefrontal cortex (PFC) activity in the AER group. Participants with a higher aerobic fitness showed lower cortisol responses to the MIST. As the Hipp and PFC are brain structures prominently involved in the regulation of the hypothalamus-pituitary-adrenal (HPA) axis, these findings indicate that the acute stress-buffering effect of exercise relies on negative feedback mechanisms. Positive affective changes after exercise appear as important moderators largely accounting for the effects related to physical fitness.
根据交叉应激适应假说，经过体育锻炼的个体对运动以外的应激源（如心理社会应激）表现出较低的生理和心理反应。应激反应性降低可能是运动对维持心理健康产生有益影响的一种作用机制。关于神经和心理神经内分泌应激反应，运动的急性应激缓冲效应尚未得到研究。将一组训练有素（HT）和久坐不动（SED）的年轻男性随机分为两组，一组在跑步机上以中等强度（60 - 70%最大摄氧量；AER）运动30分钟，另一组进行30分钟的“安慰剂”运动（PLAC）。90分钟后，使用蒙特利尔成像应激任务（MIST）的改编版本进行功能磁共振成像（fMRI）实验。评估运动干预和MIST引起的主观和心理神经内分泌（皮质醇和α - 淀粉酶）变化，以及MIST期间的神经激活情况。最后，分析不同应激反应之间的关联。AER组的参与者对MIST的皮质醇反应显著降低，这与先前运动引起的α - 淀粉酶和皮质醇波动呈负相关。关于持续的血氧水平依赖（BOLD）信号，我们发现AER组双侧海马（Hipp）活动较高，前额叶皮质（PFC）活动较低。有氧适能较高的参与者对MIST的皮质醇反应较低。由于海马和前额叶皮质是显著参与下丘脑 - 垂体 - 肾上腺（HPA）轴调节的脑结构，这些发现表明运动的急性应激缓冲效应依赖于负反馈机制。运动后积极的情感变化似乎是重要的调节因素，在很大程度上解释了与体能相关的效应。
