pISSN 2288-6982
eISSN 2288-7105



Original Article

Phys. Ther. Korea 2021; 28(4): 273-279

Published online November 20, 2021

© Korean Research Society of Physical Therapy

Effect of Backward Versus Forward Lunge Exercises on Trunk Muscle Activities in Healthy Participants

Jae-Keun Song1 , PT, MSc, Won-Gyu Yoo2 , PT, PhD

1Department of Physical Therapy, The Graduate School, 2Department of Physical Therapy, College of Biomedical Science and Engineering, Inje University, Gimhae, Korea

Correspondence to: Won-Gyu Yoo

Received: November 9, 2021; Revised: November 12, 2021; Accepted: November 12, 2021

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.


Background: Lunge exercises are lower extremity rehabilitation and strengthening exercises for patients and athletes. Most studies have shown the effectiveness of the forward and backward lunge exercises for treating patellofemoral pain and anterior cruciate ligament injuries (by increasing lower extremity muscle activity) and improving kinematics.
Objects: However, it is not known how the two different lunge movements affect trunk muscle activities in healthy individuals. The purpose of this study was to investigate the electromyographic activity of the rectus abdominis and erector spinae muscles during forward and backward lunge exercises in healthy participants.
Methods: Twelve healthy participants were recruited. Electromyographic activity of the rectus abdominis and erector spinae was recorded using surface electrodes during forward and backward lunges, and subsequently normalized to the respective reference voluntary isometric contractions of each muscle.
Results: Activity of the erector spinae was significantly higher than that of the rectus abdominis during all stages of the backward lunge (p < 0.05). The activity of the erector spinae was significantly greater during the backward than forward lunge at all stages (p < 0.05).
Conclusion: Backward lunging is better able to enhance trunk motor control and activate the erector spinae muscles.

Keywords: Electromyography, Exercise, Rectus abdominis, Visual feedback