Department for Sports Science and Physical Education, Nord University, Levanger, Trøndelag, Norway.
PeerJ. 2024 Feb 1;12:e16865. doi: 10.7717/peerj.16865. eCollection 2024.
The barbell squat is an exercise used to strengthen the lower limbs, with implications for both performance in sports and improving movement during everyday tasks. Although the exercise is being trained across a variety of repetition ranges, the technical requirements may vary, affecting appropriate repetition range for specific training goals.
A randomised within-subject design was used to compare kinematics and surface electromyography (EMG) in the lower extremities during different concentric phases (pre-, sticking- and post-sticking region) of the last repetition when performing squats at different repetition maximums (RMs). Thirteen strength-trained men (age: 23.6 ± 1.9 years; height: 181.1 ± 6.5 cm; body mass: 82.2 kg, 1RM: 122.8 ± 16.2, relative strength: 1.5 ± 0.2 x body mass in external load) performed a 1, 3, 6, and 10RM squat, in a randomised order.
The main findings were that barbell-, ankle-, knee- and hip kinematics were similar across different repetition ranges, except for a smaller trunk lean at 1RM in the pre-sticking region compared to other repetitions and in the sticking region compared to 10RM ( ≤ 0.04). Furthermore, 1RM revealed significantly higher EMG amplitude in the vastus lateralis, gastrocnemius and soleus in the sticking and post-sticking regions when compared to 10RM. It was concluded that 10RM may locally fatigue the vastus lateralis and plantar flexors, explaining the lower EMG amplitude. The observed differences indicate that requirements vary for completing the final repetition of the 10RM compared to the 1RM, an important aspect to consider in training to enhance 1RM strength.
杠铃深蹲是一种用于增强下肢力量的运动，对运动表现和日常任务中的运动能力都有影响。虽然该运动在各种重复范围内进行训练，但技术要求可能会有所不同，这会影响到特定训练目标的适当重复范围。
采用随机自身对照设计，比较了不同重复最大重量（1RM）下最后一次重复的不同向心阶段（预粘滞、粘滞和后粘滞区）下肢的运动学和表面肌电图（EMG）。13 名力量训练男性（年龄：23.6±1.9 岁；身高：181.1±6.5cm；体重：82.2kg，1RM：122.8±16.2，相对力量：1.5±0.2x体重的外部负荷）按随机顺序完成了 1、3、6 和 10RM 的深蹲。
主要发现是，除了在预粘滞区和粘滞区，1RM 的躯干前倾角度比其他重复和 10RM 都小（≤0.04），在不同重复范围内，杠铃、踝关节、膝关节和髋关节的运动学都相似，此外，与 10RM 相比，1RM 在粘滞和后粘滞区的股外侧肌、比目鱼肌和小腿三头肌的 EMG 振幅显著更高。结论是 10RM 可能会使股外侧肌和跖屈肌局部疲劳，这解释了 EMG 振幅较低的原因。观察到的差异表明，与 1RM 相比，完成 10RM 的最后一次重复的要求有所不同，这是在增强 1RM 力量的训练中需要考虑的一个重要方面。
