Citation

Hazell TJ, Sharma AK, Vanstone CA, Gagnon I, Pham TT, Finch SL, Weiler HA, Rodd CJ. Med. Sci. Sports Exerc. 2014; 46(11): 2184-2190.

Affiliation

1Mary Emily Clinical Nutrition Research Unit, School of Dietetics and Human Nutrition, McGill University, CANADA; 2Department of Pediatrics, McGill University, Montreal, Quebec, CANADA; 3School of Physical and Occupational Therapy, McGill University, Montreal, Quebec, CANADA; 4The Montreal Children's Hospital, Montreal, Quebec, CANADA.

Copyright

(Copyright © 2014, Lippincott Williams and Wilkins)

DOI

10.1249/MSS.0000000000000340

PMID

24658220

Abstract

INTRODUCTION: At the present there are limited tools available to measure muscle function in young children. Ground reaction force plates measure lower-body function and postural control in older children and adults. The purpose of this study was three-fold: 1) develop normative data for evaluating global muscle development; 2) determine the reproducibility of ground reaction force plates for assessing muscle function in preschool aged children; and 3) identify predictors of skeletal muscle function.

METHODS: Children's (n=81, 1.8 to 6.0 y; M=52%) muscle function and postural control was measured for jump (JMP), sit-to-stand (STS), and both undistracted and distracted body sway (BS) tests using a ground reaction force plate (Kistler 9200A). Whole body composition used dual-energy x-ray absorptiometry (DXA; Hologic 4500A Discovery Series). Plasma 25-hydroxyvitamin D [25(OH)D] and parathyroid hormone (PTH) concentrations were measured by chemiluminescence (Liaison, Diasorin) as well as ionized calcium (ABL80 FLEX, Radiometer Medical A/S). Demographics, and anthropometry were collected. ANOVA and linear regression were used to identify predictors. Reproducibility was assessed by intersubject coefficient of variation (CV).

RESULTS: Age was a consistent predictor in all models; body size or fat and lean mass were important predictors in 3 of the models - STS peak force, STS peak power, and JMP peak power. STS was the most reproducible manoeuvre (average CV =15.7%). Distracted BS testing was not appropriate in these youngsters.

CONCLUSION: The novel data presented in this study demonstrate a clear age (developmental) impact without any effect of sex on muscle function and postural control in young children. Lean muscle mass was important in some models (STS PF and JMP PP). The STS test was the best of the 4 manoeuvres.

Language: en