Laboratory for Functional Diagnostics, Department of Physiology, Medical School, University of Novi Sad, Serbia.
J Magn Reson Imaging. 2011 May;33(5):1114-20. doi: 10.1002/jmri.22548.
To determine the triceps brachii functional adaptation and regional body composition changes after 12 months of detraining.
Seventeen healthy young men (22.2 ± 1.0 y, body mass index 24.9 ± 3.1 kg/m(2) ) were put in the detraining regimen for 12 months after completing a 12-week exercise protocol on isoacceleration dynamometer (5 times a week, 5 daily series with 10 maximal elbow extensions, 1 min rest between sets). Triceps brachii muscle strength was measured by isoacceleration dynamometry, using identical protocol as during the training. Muscle volumes, subcutaneous adipose tissue (SCAT), and intermuscular adipose tissue (IMAT) at mid-humerus were assessed by using MRI.
Long-term detraining resulted in the significant decrease of 17% and 19% in endurance strength and fatigue rate, respectively. Maximal muscle strength slightly changed, and its 4% decrease was not significant. Triceps brachii volumes of both arms returned to their pretraining values (475.7 ± 54.91 cm(3) for right arm, and 483.9 ± 77.5 cm(3) for left arm). IMAT depots in upper arm significantly increased by 14% after 12 months of detraining, when compared with baseline values (P < 0.05).
Long-term detraining leads to triceps brachii adaptation with endurance strength decrease, volume return to its baseline values, and significant IMAT accumulation. IMAT values after 12 months of detraining exceed baseline, pretraining values, which is significant accumulation as a result of physiologically decreased muscle activity.
确定经过 12 个月停训后肱三头肌的功能适应性和身体各部位成分的变化。
17 名健康的年轻男性（22.2 ± 1.0 岁，体重指数 24.9 ± 3.1 kg/m2）在完成 12 周等速测力计运动方案（每周 5 次，每天 5 组，每组 10 次最大的肘部伸展，组间休息 1 分钟）后，进行了 12 个月的停训。肱三头肌肌力通过等速测力计进行测量，使用与训练期间相同的方案。通过 MRI 评估肱骨干中部的肱三头肌肌肉体积、皮下脂肪组织（SCAT）和肌间脂肪组织（IMAT）。
长期停训导致耐力力量下降 17%，疲劳率下降 19%。最大肌肉力量略有变化，下降 4%无统计学意义。双臂的肱三头肌体积均恢复到训练前的水平（右臂为 475.7 ± 54.91 cm3，左臂为 483.9 ± 77.5 cm3）。与基线值相比，停训 12 个月后，上臂的 IMAT 沉积显著增加了 14%（P < 0.05）。
长期停训导致肱三头肌适应性变化，耐力力量下降，体积恢复到基线值，以及显著的 IMAT 积累。停训 12 个月后的 IMAT 值超过基线值和训练前值，这是由于肌肉活动生理性减少导致的显著积累。
