Journal Article

Effects of familiarization on reliability of muscle-activation and gross efficiency in adolescents and adults

Waldron, Mark, Gray, Adrian, Highton, Jamie

2016

Overview

We investigated the effects of familiarization on the reliability of gross efficiency (GE) and lower-limb electromyography (EMG-rms) of adults and adolescents. We also evaluated the relationship between inter-test differences in GE and EMG-rms. Nine adult and nine adolescent cyclists performed three 10 min cycling tests at 50% of peak power output, separated by 48 h. Forty-five minutes familiarization visits were performed 24 h after each test. No differences were found across the tests for adult cyclists’ GE or EMG-rms, with Coefficient of Variation (CV%) ranging from 2.6 to 2.9% (GE) and 4.3 to 7.4%. Among adolescents, there was an increase in GE between tests 1 and 2 (p < 0.001) but not 2–3 (p = 0.438), with CVs decreasing from 6.8 to 2.6%. The adolescents’ EMG-rms decreased (p < 0.05) between tests 1 and 2, with CVs from 8.4 to 12.5%. There were no relationships (p > 0.05) between the inter-test differences of GE and EMG-rms. GE can be reliably determined; however, adolescents require two exposures to cycling. Without familiarization, adolescent EMG-rms is more variable than adults and would require larger samples to establish differences. The weak relationships between inter-test EMG-rms and inter-test GE questions the link between muscle activation and GE changes.

• Publisher: Taylor & Francis Ltd
• Subject: Adolescents / Adults / Bicycling / Coefficient of variation / Electromyography / Muscle contraction / Teenagers