Proceedings of The Physiological Society

Future Physiology (Leeds, UK) (2017) Proc Physiol Soc 39, PC31

Poster Communications

Preliminary Investigations into Gender Differences in Muscle Contractile Properties as Measured by Tensiomyography.

A. Jones1, M. Harrison1, P. Francis1, H. V. Wilson1

1. Musculoskeletal Health Research Group, Leeds Beckett University, Leeds, United Kingdom.

Tensiomyography is used to assess contractile properties of superficial muscles. In response to an electrical stimulation, the displacement-time curve is measured using a probe containing a sensor positioned perpendicular to the muscle belly. Maximal muscle displacement (Dm) is thought to be a measure of muscle stiffness1. Contraction time (Tc) is calculated from the displacement-time curve and has been validated against muscle fibre type2. Dm and Tc may be influenced by body composition as skinfold thickness have been reported to affect electromyographic and mechanomyographic measures. On average, women have more sub-cutaneous fat than men, meaning for Tensiomyographic assessment, the electrical current used to contract a muscle must travel a greater distance in women then in men. Additionally, the probe may be subject to greater influence from non-contractile tissues. The purpose of this preliminary investigation was to compare skinfold thickness to both Dm and Tc measures of the gastrocnemius lateralis and gluteus maximus muscles, between healthy men and women. Following ethical approval from Leeds Beckett University, Ten men (age: 25.0 ± 2.1 y; height: 177.6 ± 7.5 cm; mass: 84.0 ± 12.7 kg) and 10 women (age: 23.3 ± 2.6 y; height: 166.2 ± 6.7 cm; mass: 62.1 ± 6.3 kg) participated in this study. Skinfold thickness was measured in accordance with the International Society for Anthropometry and Kinesiology guidelines. The independent samples T-Test and Mann Whitney-U test were used to analyse the data for normal and non-normal data respectively. Skinfold thickness, Dm and Tc were not different between men and women for either the gastrocnemius lateralis or gluteus maximus(P>0.05). Dm, corrected for body mass, was greater in women compared to men for the gastrocnemius lateralis (P=0.031). However, it is possible that this study was underpowered to detect change, evidenced by a trend toward women having greater skinfold thickness and slower Tc that did not reach statistical significance. This trend was present in Dm results and in the gastrocnemius lateralis it appears that females have greater Dm relative to body mass than men. Our findings suggest that a lower body mass rather than a lower Dm is the determining factor for differences seen. Furthermore, it appears that females have greater variance in Dm and Tc data around the mean and median. Whilst it is plausible that these differences are inherent of the small study sample size, we speculate that Tensiomyography may have the capability to detect physiological gender differences in muscle contraction. Future work should be conducted in this topic area, using a larger sample size to identify significant differences.

Where applicable, experiments conform with Society ethical requirements