The accuracy of using elastic resistance bands to evaluate muscular strength

Abstract

Elastic resistance as a tool for evaluation of muscular strength has rarely been addressed even though it is commonly used in exercise and rehabilitation regimens involving the shoulder muscles. The aim was therefore to investigate the relationship and potential difference between development of force during maximal isokinetic (maximum peak force, maximum mean force and peak mean force) and elastic (one-repetition maximum (1 RM)) concentric shoulder flexion in healthy older adults. A total of 30 voluntary adults over the age of 50 (15 women, 15 men) were included. Intraclass correlation coefficient absolute agreement was 0.85, 0.43 and 0.48 for the isokinetic values respectively, when all subjects were analysed together. No difference was found between the isokinetic maximum peak force value and the elastic 1 RM for all participants (0.15 kg, p = 0.791), for men (0.80 kg, p = 0.121) or women (− 0.49 kg, p = 0.135). Variations at an individual level, i.e. 95% limits of agreement, were 3.3 kg for all participants, 2.8 kg for women and 3.2 kg for men. These results imply that elastic resistance could be used to evaluate shoulder flexion strength in both older men and women. However, the variation on an individual level and the lower agreement among women is important to consider.

Key words::

• Intraclass correlation coefficient
• isokinetic dynamometry
• one repetition maximum
• validity

Acknowledgments

We would like to thank the participants for the time and effort they spent participating in this study. We also thank Hans Stenlund and Joakim Rocklöv for statistical assistance.

Conflicts of interest: None to declare.