Department of Psychology, Technische Universität Dresden, 01062 Dresden, Germany.
Biol Psychol. 2010 May;84(2):248-56. doi: 10.1016/j.biopsycho.2010.01.019. Epub 2010 Feb 4.
The present study assessed diurnal profiles of salivary alpha-amylase (sAA), proposed as a marker of autonomic activity, and salivary cortisol in competitive ballroom dancers as well as age- and sex-matched controls to investigate age-related changes of basal activity and potential chronic psychosocial stress-related alterations. According to the Allostatic Load (AL) hypothesis of a cumulative wear and tear of the body we expected to see physiological accumulation of the effects of stress and age especially pronounced in older dancers. Dancers and controls collected five saliva samples throughout the day. Daily overall output of sAA was elevated in older adults while there was no effect of age on mean cortisol levels. Alterations of diurnal rhythms were only seen in younger male dancers showing a flattened diurnal profile of sAA and younger dancers and female older dancers showing a blunted diurnal rhythmicity of cortisol. Furthermore, we found a negative correlation between summary indices of basal sAA and the amount of physical activity. In conclusion, higher overall output of sAA in older adults is in line with the phenomenon of a sympathetic "drive" with increasing age. Furthermore, a lower output of sAA in people who are more physical active is in line with the hypothesis of an exercise-induced decrease of sympathetic activity. Overall, our study does not support the AL hypothesis, but rather highlights the importance of regular physical activity and social environment in promoting health.
本研究评估了唾液淀粉酶 (sAA) 的昼夜变化，sAA 被认为是自主活动的标志物，以及竞技舞厅舞者与年龄和性别匹配的对照组的唾液皮质醇，以调查基础活动的年龄相关性变化和潜在的慢性心理社会应激相关改变。根据身体累积磨损的适应负荷 (AL) 假说，我们预计在年龄较大的舞者中，应激和年龄的影响会更加明显地累积。舞者和对照组全天采集了五个唾液样本。老年人的 sAA 全天总输出量升高，而皮质醇的平均水平不受年龄影响。只有年轻男性舞者的昼夜节律发生改变，表现为 sAA 的昼夜模式变平，而年轻舞者和老年女性舞者的皮质醇昼夜节律变得迟钝。此外，我们发现基础 sAA 的综合指数与体力活动量之间存在负相关。总之，老年人 sAA 的整体输出增加与年龄增长时交感神经“驱动”的现象一致。此外，体力活动较多的人 sAA 输出较低，这与运动诱导的交感神经活动减少的假说一致。总的来说，我们的研究不支持 AL 假说，而是强调了定期体育活动和社会环境对促进健康的重要性。
