Repeated trials and age-related effects on performance in stabilogram, muscle steadiness and muscle strength tests
Bezerra, P, Zhou, S, Crowley, Z & Davie, AJ 2007, 'Repeated trials and age-related effects on performance in stabilogram, muscle steadiness and muscle strength tests', Australian Conference of Science and Medicine in Sport Program and Abstracts in Journal of Science and Medicine in Sport, vol. 10, no. 6 (supplement), p. 46, , Adelaide, SA, 13-16 October.
This study aimed to evaluate testing learning effects (TLE) and the reliability of the assessments in postural control, muscle steadiness of quadriceps and hamstrings on right leg, maximal voluntary contraction (MVC), and the rate of force development (RFD) of quadriceps and hamstrings on both legs in repeated testing sessions. Traditional centre of pressure (COP) and stabilogram parameters were examined on hard and soft surfaces with eyes open and closed. Muscle steadiness in isometric contraction was assessed at target forces of 5%, 15% and 25% MVC. MVC and RFD were assessed in static knee extension and flexion. Two groups of healthy volunteers, aged 20-39 (YG) and 40-59 (MG), with 10 males and 10 females in each, underwent a familiarization (day 0), trial 1 (day 5±2), and trial 2 (day 12±3). Results showed moderate to high reproducibility within tests (ICC=0.49-0.98). MVC on both legs and muscle groups showed the highest ICC (0.95-0.98). Both COP total excursion and mean velocity on anterior-posterior (AP) and medial-lateral (ML) directions and RFD have also shown high reproducibility (ICC=0.77-0.94). The lowest scores were found in COP’s stabilogram parameters (ICC=0.49-0.83). It appears there were TLE on hamstrings MVC (p<0.05) and steadiness (p<0.02) as the mean values improved significantly, and on mean distance on AP as it decreased significantly. It is recommended use the results of the first trial, after proper familiarization, as the baseline for intervention studies. The age factor didn’t influence any of the repeated measurements.