Dalgaard Line B, Dalgas Ulrik, Andersen Jesper L, Rossen Nicklas B, Møller Andreas Buch, Stødkilde-Jørgensen Hans, Jørgensen Jens Otto, Kovanen Vuokko, Couppé Christian, Langberg Henning, Kjær Michael, Hansen Mette
Section of Sport Science, Department of Public Health, Aarhus University, Aarhus, Denmark.
Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Institute of Sports Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
Front Physiol. 2019 Jul 2;10:824. doi: 10.3389/fphys.2019.00824. eCollection 2019.
The majority of young women use oral contraceptives (OCs). Use of OCs has been associated with lower myofibrillar protein and tendon collagen synthesis rates, but it is unknown whether OCs will limit the adaptive response of myotendinous tissue to resistance training. Fourteen healthy untrained young regular OC users (24 ± 1 years, fat% 32 ± 1, 35 ± 2 ml⋅min⋅kg) and 14 NOC users (non-OC, controls) (24 ± 1 years, fat% 32 ± 2, 34 ± 2 ml⋅min⋅kg) performed a 10-week supervised lower extremity progressive resistance training program. Before and after the intervention biopsies from the vastus lateralis muscle and the patellar tendon were obtained. Muscle (quadriceps) and tendon cross-sectional area (CSA) was determined by magnetic resonance imaging (MRI) scans, and muscle fiber CSA was determined by histochemistry. Maximal isometric knee extension strength was assessed by dynamometry while 1 repetition maximum (RM) was determined during knee extension. Training enhanced CSA in both muscle ( < 0.001) and tendon ( < 0.01). A trend toward a greater increase in muscle CSA was observed for OC (11%) compared to NOC (8%) (interaction = 0.06). Analysis of mean muscle fiber type CSA showed a trend toward an increase in type II muscle fiber area in both groups ( = 0.11, interaction = 0.98), whereas type I muscle fiber CSA increased in the OC group ( = 9, 3821 ± 197 to 4490 ± 313 mm, < 0.05), but not in NOC ( = 7, 4020 ± 348 to 3777 ± 354 mm, = 0.40) (interaction < 0.05). analyses indicated that the effect of OCs on muscle mass increase was induced by the OC-users ( = 7), who used OCs containing 30 μg ethinyl estradiol (EE), whereas the response in users taking OCs with 20 μg EE ( = 7) did not differ from NOC. Both the OC and NOC group experienced an increase in maximal knee strength ( < 0.001) and 1RM leg extension ( < 0.001) after the training period with no difference between groups. Use of OCs during a 10-week supervised progressive resistance training program was associated with a trend toward a greater increase in muscle mass and a significantly greater increase in type I muscle fiber area compared to controls. Yet, use of OCs did not influence the overall increase in muscle strength related to training.
大多数年轻女性使用口服避孕药（OCs）。使用OCs与较低的肌原纤维蛋白和肌腱胶原蛋白合成率有关，但尚不清楚OCs是否会限制肌腱组织对阻力训练的适应性反应。14名健康、未经训练的年轻OCs常规使用者（24±1岁，体脂率32±1，35±2毫升·分钟·千克）和14名非OCs使用者（非OCs，对照组）（24±1岁，体脂率32±2，34±2毫升·分钟·千克）进行了为期10周的下肢监督渐进性阻力训练计划。在干预前后，获取股外侧肌和髌腱的活检样本。通过磁共振成像（MRI）扫描确定肌肉（股四头肌）和肌腱横截面积（CSA），通过组织化学确定肌纤维CSA。通过测力计评估最大等长膝关节伸展力量，同时在膝关节伸展过程中确定1次重复最大值（1RM）。训练增加了肌肉（P<0.001）和肌腱（P<0.01）的CSA。与非OCs使用者（8%）相比，OCs使用者（11%）的肌肉CSA增加趋势更大（交互作用P=0.06）。平均肌纤维类型CSA分析显示，两组II型肌纤维面积均有增加趋势（P=0.11，交互作用P=0.98），而OCs组I型肌纤维CSA增加（P=9，从3821±197平方毫米增加到4490±313平方毫米，P<0.05），非OCs组则未增加（P=7，从4020±348平方毫米增加到3777±354平方毫米，P=0.40）（交互作用P<0.05）。亚组分析表明，OCs对肌肉质量增加的影响是由使用含30μg炔雌醇（EE）的OCs使用者（n=7）引起的，而服用含20μg EE的OCs使用者（n=7）的反应与非OCs使用者无差异。训练期后，OCs组和非OCs组的最大膝关节力量（P<0.001）和1RM腿部伸展（P<0.001）均增加，两组之间无差异。在为期10周的监督渐进性阻力训练计划中使用OCs，与对照组相比，肌肉质量增加趋势更大，I型肌纤维面积显著增加。然而，使用OCs并不影响与训练相关的肌肉力量总体增加。
