Faculty of Land and Food Systems, Food, Nutrition and Health, The University of British Columbia, Vancouver, BC,Canada.
Department of Health, Kinesiology and Applied Physiology, Concordia University, Montreal, QC,Canada.
J Sport Rehabil. 2023 Feb 1;32(4):385-394. doi: 10.1123/jsr.2021-0398. Print 2023 May 1.
Measures of side-to-side asymmetry in body composition may help identify players who are predisposed to lower limb injuries (LLI) or lower back pain (LBP). This study aimed to examine (1) side-to-side asymmetry in college rugby players according to sex and position and (2) whether side-to-side asymmetry is associated with LBP or LLI.
Cross-sectional study.
Thirty-six rugby players (61% female) underwent a dual-energy X-ray absorptiometry assessment for total and regional (appendicular, truncal) outcomes of fat mass, lean mass, and bone mass. A subsample (n = 23) of players had a second dual-energy X-ray absorptiometry assessment 2 months postbaseline. Two-way analysis of variance was used to assess the effect of position (forward and backs) and sex on body composition asymmetry. Student paired t tests were used to assess side-to-side difference in body composition and compare baseline and follow-up measures. Logistic regression was used to assess possible associations between LLI, LBP, and the degree of side-to-side asymmetry in body composition.
Male players had greater asymmetry in arm bone mass compared with female players (P = .026), and trunk fat mass asymmetry was greater in forwards as compared with backs (P = .017). Forwards had significantly greater fat mass (P = .004) and percentage of fat (P = .048) on the right leg compared with the left. Backs had significantly greater bone mass in the right arm compared with the left (P = .015). From baseline to postseason, forwards had a significant increase in side-to-side asymmetry in arm lean mass (P = .006) and a significant decrease in side-to-side asymmetry in leg fat mass (P = .032). In backs, side-to-side asymmetry at baseline compared with postseason was significantly different (P = .011) for trunk fat mass. There were no significant associations between body composition asymmetry, LLI, or LBP by sex or position.
Our results revealed the presence of side-to-side asymmetries in body composition in university rugby players between sex and position. The amount of asymmetry, however, was not associated with LBP and LLI.
身体成分的左右侧不对称性测量可能有助于识别易患下肢损伤（LLI）或下背痛（LBP）的运动员。本研究旨在检查：（1）根据性别和位置，大学生橄榄球运动员的左右侧不对称性；（2）左右侧不对称性是否与 LBP 或 LLI 相关。
横断面研究。
36 名橄榄球运动员（61%为女性）接受双能 X 射线吸收法评估，以获取体脂、瘦体重和骨量的总身体成分和区域（四肢、躯干）结果。运动员的一个亚组（n=23）在基线后 2 个月进行了第二次双能 X 射线吸收法评估。使用双向方差分析评估位置（前锋和后卫）和性别对身体成分不对称性的影响。使用学生配对 t 检验评估身体成分的左右侧差异，并比较基线和随访测量值。使用逻辑回归评估 LLI、LBP 和身体成分左右侧不对称程度之间的可能关联。
与女性运动员相比，男性运动员手臂骨量的不对称性更大（P=.026），而前锋与后卫相比，躯干脂肪量的不对称性更大（P=.017）。前锋的右腿脂肪量（P=.004）和脂肪百分比（P=.048）明显大于左腿。后卫的右臂骨量明显大于左臂（P=.015）。从基线到季后赛，前锋手臂瘦体重的左右侧不对称性显著增加（P=.006），腿部脂肪量的左右侧不对称性显著降低（P=.032）。在后卫中，与季后赛相比，基线与季后赛的躯干脂肪量的左右侧不对称性差异具有统计学意义（P=.011）。性别和位置的身体成分不对称性、LLI 或 LBP 之间无显著关联。
本研究结果显示，大学生橄榄球运动员的身体成分存在左右侧不对称性，这种不对称性存在于性别和位置之间。然而，不对称性的程度与 LBP 和 LLI 无关。
