Irving Brian A, Lanza Ian R, Henderson Gregory C, Rao Rajesh R, Spiegelman Bruce M, Nair K Sreekumaran
Division of Endocrinology (B.A.I., I.R.L., G.D.H., K.S.N.), Endocrine Research Unit, Mayo Clinic College of Medicine, Rochester, Minnesota 55905; Department of Cancer Biology (R.R.R., B.M.S.), Dana-Farber Cancer Institute, Boston, Massachusetts 02215; and Department of Cell Biology (R.R.R., B.M.S.), Harvard Medical School, Boston, Massachusetts 02215.
J Clin Endocrinol Metab. 2015 Apr;100(4):1654-63. doi: 10.1210/jc.2014-3081. Epub 2015 Jan 19.
Skeletal muscle from sedentary older adults exhibits reduced mitochondrial abundance and oxidative capacity.
The primary objective was to determine whether 8 weeks of combined training (CT) has a more robust effect than endurance training (ET) or resistance training (RT) on mitochondrial physiology in healthy young (18-30 years) and older (≥ 65 years) adults.
Thirty-four young and 31 older adults were randomly assigned to 8 weeks of ET, RT, and control/CT. Control subjects completed 8 weeks of no exercise (control) followed by 8 weeks of CT. Body composition, skeletal muscle strength, and peak oxygen uptake were measured before and after the intervention. Vastus lateralis muscle biopsy samples were obtained before and 48 hours after the intervention. Mitochondrial physiology was evaluated by high-resolution respirometry and expression of mitochondrial proteins and transcription factors by quantitative PCR and immunoblotting.
ET and CT significantly increased oxidative capacity and expression of mitochondrial proteins and transcription factors. All training modalities improved body composition, cardiorespiratory fitness, and skeletal muscle strength. CT induced the most robust improvements in mitochondria-related outcomes and physical characteristics despite lower training volumes for the ET and RT components. Importantly, most of the adaptations to training occurred independent of age.
Collectively, these results demonstrate that both ET and CT increase muscle mitochondrial abundance and capacity although CT induced the most robust improvements in the outcomes measured. In conclusion, CT provides a robust exercise regimen to improve muscle mitochondrial outcomes and physical characteristics independent of age.
久坐不动的老年人的骨骼肌线粒体丰度和氧化能力降低。
主要目的是确定8周的联合训练（CT）对健康年轻人（18 - 30岁）和老年人（≥65岁）的线粒体生理学的影响是否比耐力训练（ET）或阻力训练（RT）更显著。
34名年轻人和31名老年人被随机分配到进行8周的ET、RT和对照/CT组。对照组受试者先进行8周不运动（对照），然后进行8周的CT。在干预前后测量身体成分、骨骼肌力量和峰值摄氧量。在干预前和干预后48小时获取股外侧肌活检样本。通过高分辨率呼吸测定法评估线粒体生理学，并通过定量PCR和免疫印迹法评估线粒体蛋白和转录因子的表达。
ET和CT显著提高了氧化能力以及线粒体蛋白和转录因子的表达。所有训练方式都改善了身体成分、心肺适能和骨骼肌力量。尽管ET和RT部分的训练量较低，但CT在线粒体相关结果和身体特征方面带来了最显著的改善。重要的是，大多数训练适应性变化与年龄无关。
总体而言，这些结果表明ET和CT都增加了肌肉线粒体丰度和能力，尽管CT在测量的结果方面带来了最显著的改善。总之，CT提供了一种有效的运动方案，可改善肌肉线粒体结果和身体特征，且与年龄无关。
