Interplay Between Adiposity and Clinical Measurements of Lower Extremity Neuromuscular Performance in Children

Research Objectives: To determine if adiposity (%total body fat( is related to clinical measurements of lower extremity neuromuscular performance (sit-to-stand test, STS; lateral step-up test; LSUT at 0.05 and 0.015 m) in children. Whether these relationships are affected by age, sex, and height.

Design: Cross-sectional study.

Setting: University Laboratory

Participants: Children (n=21; 40% male) ages 8-13 years.

Interventions: Not applicable.

Main Outcome Measures: We used LSUT0.05, LSUT0.15, and STS to determine neuromuscular performance. LSUT0.05, LSUT0.15, and STS were assessed in random order after a familiarization session. Maximum counts achieved during testing LSUT0.05, LSUT0.15 and STS were normalized for body weight. A bio-impedance analysis device was used to assess %total body fat.

Results: %total body fat was negatively related to STS (rspearman= -0.5, p < 0.05). %total body fat was negatively related to body weight normalized STS, LSUT0.05 and LSUT0.015 (rspearman= -0.7 to -0.82, p < 0.01). These negative relationships existed after adjusting for age (rpartial = -0.77 to -0.82, p < 0.001), height (rpartial = -0.66 to -0.8, p < 0.01), and sex (rpartial = -0.69 to -0.8, p < 0.001).

Conclusions: Our findings show an inverse association of adiposity and neuromuscular performance in children, independent of age, sex, and height. Specifically, these findings were evident or became stronger after adjusting the outputs of neuromuscular performance tests for body weight. Our findings have critical implications for the interpretation of the neuromuscular clinical tests and neuromuscular development in children with obesity.

Author(s) Disclosures: No conflict.