Affiliations: [a] Sports Movement Artificial-Intelligence Robotics Technology (SMART) Institute, Department of Physical Therapy, Yonsei University, Wonju, Korea | [b] Department of Physical Therapy, Yonsei University, Wonju, Korea | [c] Department of Physical Therapy, Cheju Halla University, Jeju, Korea
Correspondence:
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Corresponding author: Joshua (Sung) H. You, Sports Movement Artificial-Intelligence Robotics Technology (SMART) Institute, Department of Physical Therapy, 1 Yonseidae-gil, Wonju, Kangwon-do 26493, Korea. Tel.: +82 33 760 2476; Fax: +82 33 760 2496; E-mail: neurorehab@yonsei.ac.kr.
Abstract: BACKGROUND: Although the instrument-assisted manual (IM) technique has been widely utilised to improve soft tissue and joint mobility, its therapeutic benefits and underlying neuromechanical mechanisms remain unknown compared to those of conventional static stretching (SS) and hold-relax (HR) manual techniques. OBJECTIVE: This study aimed to compare the effects of the SS, HR, and IM techniques on muscle activity, kinematics, and strength during deep squatting in limited ankle dorsiflexion (DF) syndrome. METHODS: This was a cross-sectional randomised controlled study including 39 adults divided into three groups: SS group: 13, HR group: 13, IM group: 13. Outcome measures were the tibialis anterior (TA): gastrocnemius (GCM) balance ratio and ankle, knee, hip and thoracolumbar junction angles. TA muscle strength was analysed to evaluate the limited ankle DF. Analysis of variance was performed, with P< 0.05. RESULTS: The TA:GCM balance ratio, ranges of motion of ankle DF and knee flexion, and TA muscle strength in the IM group improved significantly compared to that in either the SS group or HR group (P< 0.05). CONCLUSIONS: Our novel results demonstrated that IM was most effective in normalising TA:GCM balance, ankle DF range of motion, and TA muscle strength during deep squatting in adults with limited ankle DF.
Keywords: Ankle dorsiflexion, deep squatting, hold-relax, static stretching, manual technique
