The trunk and pelvis kinematics of 20 healthy male and female adolescent rowers were recorded during an ergometer trial using an electromagnetic tracking system (Fastrak). The kinematics of each drive phase were collected during the 1st and 20th minute, respectively. The mean and range of the kinematics, stroke rate and stroke length were compared between genders and over time. Male rowers postured their pelvis with more posterior tilt and their thoracic spine in more flexion than female rowers (P < .05). Both genders postured their pelvis in more posterior pelvic rotation and upper trunk in more flexion over time. Male rowers were found to have a significantly shorter drive phase than female rowers (P = .001). Differences in trunk and pelvic kinematics between adolescent male and female rowers suggest potentially various mechanisms for biomechanical stress. Assessment and training of rowers should take gender differences into consideration.
Leo Ng, Amity Campbell, Angus Burnett and Peter O’Sullivan
Jonathan Leo Ng, Chris Button, Dave Collins, Susan Giblin and Gavin Kennedy
Validated assessment tools for movement competence typically involve the isolation and reproduction of specific movement forms, which arguably neglects individuals’ ability to combine and adapt movements to overcome constraints within a dynamic environment. A new movement assessment tool, the General Movement Competence Assessment (GMCA), was developed for this study using Microsoft Kinect. Movement competence of 83 children (36 boys and 47 girls), aged 8–10 years (9.06 ± 0.75 years) was measured using the GMCA. An exploratory approach was undertaken to examine the internal consistency reliability (McDonald’s omega coefficient) and factorial structure of the GMCA for the study sample. Factorial structure was determined using exploratory factor analysis by principal component analysis with varimax rotation. For the sample data, reliability for the GMCA games were acceptable (ω = 0.53–0.89) and indicated that combinations of movement attributes were measured by GMCA games. Factorial analysis extracted four movement constructs accounting for 71.31% of variance. Dexterity was tentatively identified as a new independent construct alongside currently accepted movement constructs (i.e., locomotion, object-control, stability). While further development of the GMCA is still required, initial results are encouraging in view of an objective and theoretically informed approach to assess general movement competence in children.
Leo Ng, Amity Campbell, Angus Burnett, Anne Smith and Peter O’Sullivan
There is a high prevalence of low back pain (LBP) in adolescent male rowers. In this study, regional lumbar spinal kinematics and self-reported LBP intensity were compared between 10 adolescent rowers with moderate levels of LBP relating to rowing with 10 reporting no history of LBP during a 15-minute ergometer trial using an electromagnetic tracking system. Adolescent male rowers with LBP reported increasing pain intensity during ergometer rowing. No significant differences were detected in mean upper or lower lumbar angles between rowers with and without LBP. However, compared with rowers without pain, rowers with pain: (1) had relatively less excursion of the upper lumbar spine into extension over the drive phase, (2) had relatively less excursion of the lower lumbar spine into extension over time, (3) had greater variability in upper and lower lumbar angles over the 15-minute ergometer trial, (4) positioned their upper lumbar spine closer to end range flexion for a greater proportion of the drive phase, and (5) showed increased time in sustained flexion loading in the upper lumbar spine. Differences in regional lumbar kinematics exist between adolescent male rowers with and without LBP, which may have injury implication and intervention strategies.