Department of Kinesiology, Mississippi State University, Starkville, MS 39762, USA.
Med Sci Sports Exerc. 2013 Feb;45(2):379-86. doi: 10.1249/MSS.0b013e318270b381.
Studies have demonstrated that a combination of mental and physical challenge can elicit exacerbated state anxiety, effort sense, and cortisol responses above that of a single stimulus. However, an analysis of the effects of aerobic fitness on the responses of cortisol to concurrent mental and physical stress between below average and above average fitness individuals has not been conducted. This study examined the effects of a combination of acute mental challenges and physical stress on psychological and cortisol responses between eight individuals of below average fitness (low fit (LF), VO2max = 36.58 ± 3.36 mL·kg(-1)·min(-1)) and eight individuals of above average fitness (high fit (HF), VO2max = 51.18 ± 2.09 mL·kg(-1)·min).
All participants completed two experimental conditions. An exercise-alone condition (EAC) consisted of cycling at 60% VO2max for 37 min, and a dual-challenge condition (DCC) included concurrent participation in a mental challenge for 20 min while cycling.
The DCC resulted in increases in state anxiety (P = 0.018), perceived overall workload (P = 0.001), and exacerbated cortisol responses (P = 0.04). Furthermore, LF participants had a greater overall cortisol response in the DCC compared with the EAC (DCC = 346.83 ± 226.92; EAC = -267.46 ± 132.32; t7 = 2.49, P = 0.04), whereas HF participants demonstrated no difference between conditions (DCC = 38.91 ± 147.01; EAC = -324.60 ± 182.78; t7 = 1.68, P = 0.14).
LF individuals seem to demonstrate unnecessary and unfavorable responses to the DCC compared with HF individuals, particularly concerning cortisol. The exacerbated cortisol responses in LF individuals have implications for harmful consequences such as increased risk of cardiovascular disease.
研究表明，心理和身体挑战的结合会引起更严重的状态焦虑、努力感和皮质醇反应，超过单一刺激的反应。然而，对于有氧健身对皮质醇对低于平均和高于平均健身个体的同时心理和身体压力的反应的影响的分析尚未进行。本研究检查了急性心理挑战和身体应激的组合对 8 名身体条件低于平均水平（低 fit（LF），VO2max = 36.58 ± 3.36 mL·kg(-1)·min(-1))和 8 名身体条件高于平均水平（高 fit（HF），VO2max = 51.18 ± 2.09 mL·kg(-1)·min(-1)）的个体的心理和皮质醇反应的影响。
所有参与者完成了两个实验条件。单独运动条件（EAC）包括以 60% VO2max 骑行 37 分钟，双重挑战条件（DCC）包括在骑行时同时进行 20 分钟的心理挑战。
DCC 导致状态焦虑增加（P = 0.018），感知整体工作量增加（P = 0.001），皮质醇反应加剧（P = 0.04）。此外，LF 参与者在 DCC 中的整体皮质醇反应大于 EAC（DCC = 346.83 ± 226.92；EAC = -267.46 ± 132.32；t7 = 2.49，P = 0.04），而 HF 参与者在两种条件之间没有差异（DCC = 38.91 ± 147.01；EAC = -324.60 ± 182.78；t7 = 1.68，P = 0.14）。
LF 个体似乎与 HF 个体相比，对 DCC 表现出不必要和不利的反应，特别是皮质醇。LF 个体皮质醇反应加剧对心血管疾病风险增加等有害后果有影响。
