During the COVID-19 challenges, isometric training may be a viable programming option. As such, the CSCA interviewed Danny Lum co-author of a review paper on isometric training to gain his insights.
Full citation: Lum, Danny and Barbosa, Tiago. Brief Review: Effects of Isometric Strength Training on Strength and Dynamic Performance. International Journal of Sports Medicine. 2019; 40:363-375.
CSCA – Danny, please introduce yourself to our readers.
DL – I am the Team Lead for Strength and Conditioning at the Singapore Sport Institute. I am also undergoing my PhD study at Nanyang Technological University. My main areas of interest include isometric strength training and testing, and post activation potentiation.
CSCA – Do you also serve as a strength and conditioning coach?
DL – I am currently the strength and conditioning coach for some of our national athletes. Teams that I work with include, bowling, cycling, diving, kayaking, and grappling sports.
CSCA – What led you to review the area of isometric training (and testing)?
DL – I first included the isometric mid-thigh pull test to assess the strength of our judo athletes. I also included isometric exercises into their strength training program as judo athletes get into a fair amount of isometric muscle contractions during each bout. I realized that the inclusion of isometric exercises actually benefited their overall physical performance, so I started getting interested in the science behind this method of strength training.
CSCA – What are the 3 key points you would like readers to take away from your paper?
DL – Firstly, although isometric strength training is effective in increasing muscular strength, the level of benefit to dynamic movement performance is still inferior to a dynamic mode of strength training. Therefore, isometric strength training should be included as part of a strength training program that includes the dynamic movements s as well (e.g., 2 sets of isometric squats + 2 sets of dynamic squats). However, if athletes are not able to perform a dynamic version of the exercise due to injury, or other reasons, they can be assured that improvements are still possible by performing isometric strength training alone.
Secondly, similar to dynamic exercises, athletes should have the intent to contract the muscle as rapidly and as forcefully as possible when performing isometric exercises. This will result in not only an increase in maximum strength but also an increase in the rate of force development, which is a very important attribute in sports performance. Based on the current literature, a sustained contraction of 1-5 seconds per repetition and 30-90 seconds per session is recommended for improving maximum strength.
Thirdly, isometric strength training is more effective in improving maximum force development at a specific angle as compared to a dynamic mode of strength training. Therefore, it is recommended to perform isometric strength training at the joint angle that reflects the most biomechanically disadvantaged position of a specific movement (i.e., a sticking point), or at the joint angle where the concentric phase of the particular movement is initiated.