Medical News Observer

Key Points:

• Bioelectrical impedance analysis ‘s phase angle measurement strongly correlated with muscle health.
• The research highlights the phase angle as a key biomarker for muscle health, useful in routine physical evaluations.
• The potential use of bioelectrical impedance analysis could aid in monitoring muscle-related health issues in the geriatric population.

Overview

The WHO estimates that by 2050, the global population aged 60 years and older will double to 2.1 billion, up from 1 billion in 2020. This trend is particularly notable in Japan, where 29.1% of the population was 65 or older in 2022. And this figure is expected to rise to 34.8% by 2040. The growing aging population brings health challenges, including the risks of losing muscle mass and strength, such as increased falls, inactivity, and metabolic problems. There is a need for developing non-invasive, easy-to-use tests for measuring muscle health.

Bioelectrical impedance analysis (BIA) for measuring muscle health

A team of researchers from the University of Tsukuba has explored using bioelectrical impedance analysis (BIA) for measuring muscle health. BIA is a non-invasive method for assessing the body’s electrical properties, with phase angle being a key measurement that reflects muscle quantity and quality. 

Study

Their study, published in Frontiers in Physiology, aimed to explore the association between phase angle and neuromuscular properties in 60 adults aged 21 to 83. The phase angle of the right leg was measured using bioelectrical impedance analysis. Simultaneously, researchers evaluated various muscle contractile properties, including twitch and maximal voluntary isometric contractions of the plantar flexors.

Results

The findings showed significant correlations between phase angle and muscle contractile properties, such as peak twitch torque, rate of torque development, and maximal muscle strength. However, there was no significant correlation with normalized rate of torque development or electromyographic activity. 

Importance

These results position the phase angle as a valuable biomarker for muscular health assessment. This can be monitored using devices like weight scales with integrated body composition analyzers. Thus offering an easy and quick method for physical evaluation. This is especially crucial as conditions like sarcopenia become more prevalent in the aging population.

Reference

Hirata, Kosuke, Yosuke Yamada, Natsuki Iida, Akihiro Kanda, Mikio Shoji, Tsukasa Yoshida, and Ryota Akagi. 2023. “Relation of Leg Phase Angle from Bioelectrical Impedance Analysis with Voluntary and Evoked Contractile Properties of the Plantar Flexors.” Frontiers in Physiology 14. https://www.frontiersin.org/articles/10.3389/fphys.2023.1292778.