Kannas Theodoros M, Stefanis Georgios, Kousinas Apostolis, Chalatzoglidis Georgios, Arabatzi Fotini
Laboratory of Neuromechanics, Department of Physical Education and Sport Science, Aristotle University of Thessaloniki, Serres, Thessaloniki, GRC.
Laboratory of Neuromechanics, Department of Physical Education and Sport Science, Aristotle University of Thessaloniki, Serres, GRC.
Cureus. 2023 Aug 11;15(8):e43346. doi: 10.7759/cureus.43346. eCollection 2023 Aug.
Flexibility seems to be an essential part of both the training and rehabilitation processes. Several stretching techniques have been used to improve the range of motion (ROM) of the joints with the proprioceptive neuromuscular facilitation (PNF) method being the most effective one. Although plantar flexors are ideal to compare the acute effects of synergistic muscle groups on performance, it is not clear whether the PNF stretch at different muscle lengths could result in different alterations.
Sixteen male students randomly performed 2 levels of stretching (PNF with bended knees, or PNFshort, and with extended knee, or PNFlong) and 3 types of jumps, separated by 48 hours (7 sessions in total). Jumping parameters were recorded by a force plate, and the final jumping height (H) and ground reaction forces (Fz) were analyzed. Furthermore, the ROM of the ankle joint was recorded before, right after, and 15 minutes after the stretches. Results: The ankle joint's ROM joint was increased after both interventions. No significant changes were found in the jumping height of all jumps. The Fz, during the squat jump (SJ) and countermovement jump (CMJ), were increased after PNFshort. Similarly, a significant increase was found in Fz in drop jumps (DJ) right after the PNFshort.
Our findings demonstrated that PNF stretches of different lengths could potentially alter the stretch-shortening cycle's performance, possibly leading to a non-optimal muscle-tendon interaction.
灵活性似乎是训练和康复过程的重要组成部分。已经使用了几种拉伸技术来改善关节的活动范围（ROM），其中本体感觉神经肌肉促进法（PNF）是最有效的一种。尽管跖屈肌是比较协同肌群对运动表现急性影响的理想对象，但尚不清楚不同肌肉长度下的PNF拉伸是否会导致不同的变化。
16名男学生随机进行2种拉伸水平（屈膝PNF，即PNF短；伸膝PNF，即PNF长）和3种跳跃，间隔48小时（共7次训练）。通过测力台记录跳跃参数，并分析最终跳跃高度（H）和地面反作用力（Fz）。此外，在拉伸前、拉伸后即刻以及拉伸后15分钟记录踝关节的ROM。结果：两种干预后踝关节的ROM均增加。所有跳跃的跳跃高度均未发现显著变化。PNF短拉伸后，深蹲跳（SJ）和反向纵跳（CMJ）期间的Fz增加。同样，PNF短拉伸后即刻，跳深（DJ）中的Fz显著增加。
我们的研究结果表明，不同长度的PNF拉伸可能会改变拉长-缩短周期的表现，可能导致肌肉-肌腱相互作用不理想。
