Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC 27106, USA.
Translational Science Center, Wake Forest University, Winston-Salem, NC 27106, USA.
Nutrients. 2022 Jun 30;14(13):2739. doi: 10.3390/nu14132739.
Many studies have evaluated the effects of resistance training (RT) and protein intake to attenuate the age-related loss of skeletal muscle. However, the effects of graded protein intake with conjunctive RT in older adults are unclear. Older adults (n = 18) performed 10 weeks of whole-body RT with progressions to intensity and volume while consuming either a constant protein (CP) diet (0.8−1.0 g/kg/d) with no protein supplement or a graded protein (GP) diet progressing from 0.8 g/kg/d at week 1 to 2.2 g/kg/d at week 10 with a whey protein supplement. Data were collected prior to commencement of the RT protocol (PRE), after week 5 (MID), and after week 10 (POST). Dual Energy X-ray Absorptiometry derived lean/soft tissue mass, ultrasonography derived muscle thickness, and a proxy of muscle quality were taken at PRE and POST, while isokinetic dynamometry derived peak torque were taken at PRE, MID, and POST. This study demonstrated the feasibility of the RT protocol (attendance = 96%), and protein intake protocol (CP in range all weeks; GP deviation from prescribed = 7%). Peak torque, muscle quality scores, and appendicular lean/soft tissue mass demonstrated the main effects of time (p < 0.05) while no other main effects of time or group * time interactions were seen for any measure. In conclusion, RT improved appendicular lean/soft tissue mass, peak torque, and muscle quality, with no differential effects of graded or constant protein intake.
许多研究已经评估了抗阻训练（RT）和蛋白质摄入对减缓与年龄相关的骨骼肌丧失的影响。然而，在老年人中，分级蛋白质摄入与联合 RT 的效果尚不清楚。老年人（n = 18）进行了 10 周的全身 RT，强度和量逐渐增加，同时摄入恒定蛋白质（CP）饮食（0.8-1.0 g/kg/d），没有蛋白质补充剂，或分级蛋白质（GP）饮食，从第 1 周的 0.8 g/kg/d 逐渐增加到第 10 周的 2.2 g/kg/d，补充乳清蛋白。数据在 RT 方案开始前（PRE）、第 5 周（MID）和第 10 周（POST）收集。在 PRE 和 POST 时进行双能 X 射线吸收法测量瘦体/软组织质量、超声测量肌肉厚度和肌肉质量的替代指标，在 PRE、MID 和 POST 时进行等速动力学测量峰值扭矩。本研究证明了 RT 方案（出勤率 = 96%）和蛋白质摄入方案（CP 在所有周内均在范围内；GP 与规定值的偏差 = 7%）的可行性。峰值扭矩、肌肉质量评分和四肢瘦体/软组织质量显示时间的主要影响（p < 0.05），而任何测量均未显示时间或组*时间相互作用的其他主要影响。总之，RT 提高了四肢瘦体/软组织质量、峰值扭矩和肌肉质量，而分级或恒定蛋白质摄入没有差异影响。
