Changes in Torso Muscle Endurance Profiles in Children Aged 7 to 14 Years: Reference Values

Dejanovic A, Harvey EP, McGill SM. Changes in torso muscle endurance profiles in children aged 7 to 14 years: reference values.ObjectiveTo establish torso muscle endurance values in children aged 7 to 14 years, as well as ratios between torso extensors, flexors, and lateral torso flexors, with applications in clinical assessment, rehabilitation, physical education targets, and athletic training program designs. It was hypothesized that boys and girls mature differently in terms of torso muscle endurance.DesignMeasurements of torso muscle endurance were performed by using 4 tests in healthy children.SettingElementary school in Novi Sad, Province of Vojvodina, Republic of Serbia.ParticipantsChildren from 1 elementary school (N=753, n=394 boys and n=359 girls) were grouped into 8 age strata.InterventionsNot applicable.Main Outcome MeasuresFour tests established isometric physical endurance: Biering–Sørensen test for extensor endurance, flexor endurance test, and right- and left-side bridge tests. The mean, ratio, standard deviation, and 25th, 50th, and 75th percentile scores were determined for each sex/age stratum.ResultsA 2-way analysis of variance indicated that girls had higher mean endurance times for torso extension and torso flexion than did boys. For example, times measured by using Biering–Sørensen and right-side bridge tests were significantly greater for girls than for boys across all age groups (P<.023). Boys can sustain the side torso test longer than can girls. Furthermore, 3-dimensional torso muscle endurance is under significant impact of age. Tukey Honestly Significant Difference post hoc tests confirmed that within and between sex exist significant differences in mean endurance times in all age strata at the significance level P=.05.ConclusionBoth age and sex influence differences in torso endurance in children aged 7 to 14 years. These data of endurance times, their ratios, and percentiles in healthy subjects form a database that may be useful for providing training and rehabilitation targets.