Supplementary information files for Fast and ballistic contractions involve greater neuromuscular power production in older adults during resistance exercise

Supplementary Information files for article Fast and ballistic contractions involve greater neuromuscular power production in older adults during resistance exercise

Purpose: 
Neuromuscular power is critical for healthy ageing. Conventional older adult resistance training (RT) guidelines typically recommend lifting slowly (2-s; CONV), whereas fast/explosive contractions performed either non-ballistically (FAST-NB) or ballistically (FAST-B, attempting to throw the load) may involve greater acute power production, and could ultimately provide a greater chronic power adaptation stimulus. To compare the neuromechanics (power, force, velocity, and muscle activation) of different types of concentric isoinertial RT contractions in older adults. 
Methods: 
Twelve active older adult males completed three sessions, each randomly assigned to one type of concentric contraction (CONV or FAST-NB or FAST-B). Each session involved lifting a range of loads (20–80%1RM) using an instrumented isoinertial leg press dynamometer that measured power, force, and velocity. Muscle activation was assessed with surface electromyography (sEMG). 
Results: 
Peak and mean power were markedly different, according to the concentric contraction explosive intent FAST-B > FAST-NB > CONV, with FAST-B producing substantially more power (+ 49 to 1172%, P ≤ 0.023), force (+ 10 to 136%, P < 0.05) and velocity (+ 55 to 483%, P ≤ 0.025) than CONV and FAST-NB contractions. Knee and hip extensor sEMG were typically higher during FAST-B than CON (all P < 0.02) and FAST-NB (≤ 50%1RM, P ≤ 0.001). 
Conclusions: 
FAST-B contractions produced markedly greater power, force, velocity and muscle activation across a range of loads than both CONV or FAST-NB and could provide a more potent RT stimulus for the chronic development of older adult power.

《快速与弹跳式收缩在老年成年人抗阻训练中涉及更大的神经肌肉力量产生》的补充信息文件

目的：
神经肌肉力量对健康老龄化至关重要。传统的老年抗阻训练（RT）指南通常建议缓慢举重（2秒；CONV），而执行快速/爆炸性收缩（FAST-NB）或弹跳式收缩（FAST-B，试图抛掷负荷）可能涉及更大的急性力量产生，并可能最终提供更大的慢性力量适应刺激。本研究旨在比较老年人在不同类型的同轴同惯性抗阻训练收缩中的神经机械学（力量、力、速度和肌肉激活）。

方法：
12名活跃的老年男性完成了三组实验，每组随机分配到一种同轴收缩类型（CONV、FAST-NB或FAST-B）。每组实验涉及使用测量力量、力和速度的仪器同惯性腿部推举动力仪，以不同负荷范围（20-80%1RM）进行举重。肌肉激活通过表面肌电图（sEMG）进行评估。

结果：
根据同轴收缩的爆炸意图（FAST-B > FAST-NB > CONV），峰值和平均力量显著不同，FAST-B在产生力量（增加49至1172%，P ≤ 0.023）、力（增加10至136%，P < 0.05）和速度（增加55至483%，P ≤ 0.025）方面，均显著高于CONV和FAST-NB收缩。在FAST-B期间，膝关节和髋关节伸展肌的sEMG通常高于CON（所有P < 0.02）和FAST-NB（≤50%1RM，P ≤ 0.001）。

结论：
与CONV或FAST-NB相比，FAST-B收缩在广泛负荷范围内产生了显著更高的力量、力、速度和肌肉激活，并可能为老年成年人慢性力量发展的更有效抗阻训练刺激提供更强大的动力。