Shute Robert, Marshall Katherine, Opichka Megan, Schnitzler Halee, Ruby Brent, Slivka Dustin
School of Health and Kinesiology, University of Nebraska at Omaha, Omaha, Nebraska.
School of Integrative Physiology and Athletic Training, University of Montana, Missoula, Montana.
J Appl Physiol (1985). 2020 Apr 1;128(4):768-777. doi: 10.1152/japplphysiol.00500.2019. Epub 2020 Feb 27.
Cold environmental temperatures during exercise and recovery alter the acute response to cellular signaling and training adaptations. Approximately 3 wk is required for cold temperature acclimation to occur. To determine the impact of cold environmental temperature on training adaptations, fitness measurements, and aerobic performance, two groups of 12 untrained male subjects completed 1 h of cycling in 16 temperature acclimation sessions in either a 7°C or 20°C environmental temperature. Fitness assessments before and after acclimation occurred at standard room temperature. Muscle biopsies were taken from the vastus lateralis muscle before and after training to assess molecular markers related to mitochondrial development. Peroxisome proliferator-activated receptor-γ coactivator 1α () mRNA was higher in 7°C than in 20°C in response to acute exercise before training ( = 0.012) but not after training ( = 0.813). mRNA was lower after training ( < 0.001). was lower after training in the 7°C than in the 20°C group ( = 0.017) but not before training ( = 0.549). No other differences occurred between temperature groups in , or mRNAs ( > 0.05). PGC-1α protein and mtDNA were not different before training, after training, or between temperatures ( > 0.05). Cycling power increased during the daily training ( < 0.001) but was not different between temperatures ( = 0.169). V̇o increased with training ( < 0.001) but was not different between temperature groups ( = 0.460). These data indicate that a 3-wk period of acclimation/training in cold environmental temperatures alters PGC-1α gene expression acutely but this difference is not manifested in a greater increase in V̇o and is dissipated as acclimation takes place. This study examines the adaptive response of cellular signaling during exercise in cold environmental temperatures. We demonstrate that peroxisome proliferator-activated receptor-γ coactivator 1α mRNA is different between cold and room temperature environments before training but after training this difference no longer exists. This initial difference in transcriptional response between temperatures does not lead to differences in performance measures or increases in protein or mitochondria.
运动及恢复过程中的寒冷环境温度会改变细胞信号传导的急性反应和训练适应性。寒冷温度适应大约需要3周时间。为了确定寒冷环境温度对训练适应性、体能测量及有氧能力的影响，两组各12名未经训练的男性受试者在16次温度适应训练中，分别于7°C或20°C的环境温度下进行了1小时的骑行。适应训练前后的体能评估均在标准室温下进行。训练前后均从股外侧肌采集肌肉活检样本，以评估与线粒体发育相关的分子标志物。训练前急性运动后，过氧化物酶体增殖物激活受体γ共激活因子1α（）的mRNA在7°C时高于20°C（ = 0.012），但训练后则无此差异（ = 0.813）。训练后mRNA水平降低（ < 0.001）。7°C组训练后的水平低于20°C组（ = 0.017），但训练前无此差异（ = 0.549）。温度组之间在、或mRNA方面未出现其他差异（ > 0.05）。训练前、训练后及不同温度之间，PGC - 1α蛋白和线粒体DNA均无差异（ > 0.05）。每日训练期间骑行功率增加（ < 0.001），但不同温度之间无差异（ = 0.169）。随着训练，摄氧量增加（ < 0.001），但温度组之间无差异（ = 0.460）。这些数据表明，在寒冷环境温度下进行3周的适应/训练会急性改变PGC - 1α基因表达，但这种差异并未表现为摄氧量的更大增加，且随着适应过程的进行而消失。本研究考察了寒冷环境温度下运动期间细胞信号传导的适应性反应。我们证明，训练前过氧化物酶体增殖物激活受体γ共激活因子1α的mRNA在寒冷和室温环境之间存在差异，但训练后这种差异不再存在。温度之间转录反应的这种初始差异并未导致性能指标的差异，也未使蛋白质或线粒体增加。
