Department of Taekwondo, College of Physical Education, Kyung Hee University (Global campus), 1732 Deokyoungdaero, Giheung-gu, Yongin-si, Gyeonggi-do 17014, Korea.
Department of Kinesiology, College of Communication and Education, California State University-Chico, 400 West First Street, Chico, CA 95922, USA.
Int J Environ Res Public Health. 2019 Sep 14;16(18):3422. doi: 10.3390/ijerph16183422.
The purpose of this study was to examine the associations of vitamin D status with athletic performance and blood-borne markers in adolescent athletes. This cross-sectional study included forty-seven Taekwondo athletes, aged 15-18 years old. Athletic performance was assessed using maximal oxygen consumption (VO), Wingate anaerobic power test, vertical jump, agility T-test, lower limb muscle strength, and fatigue resistance. Blood samples were collected to assess serum 25-hydroxyvitamin D [25(OH)D], free-testosterone, cortisol, creatine kinase, and urea. One-way ANOVAs were applied using Bonferroni adjusted alpha levels, which was 0.02 (i.e., 0.05/3). Multiple linear regressions analyses as well as Pearson and partial correlation analyses were used to examine the relationship among 25(OH)D concentration, athletic performance, and blood-borne markers. The participants 25(OH)D concentration were ranged from 16 to 73.25 nmol/L, indicating that 74.5% of the adolescent athletes have vitamin D insufficiency or deficiency. The vitamin D status did not show any significant effects on the performance factors or blood-borne markers. Serum 25(OH)D concentration was positively correlated with mean power output (r = 0.359, < 0.05) and relative mean power output (r = 0.325, < 0.05) after adjusting for bone age, height, weight, training experience, lean body mass, and fat mass. However, 25(OH)D concentration was not associated with other performance-related factors and blood-borne markers. In addition, multiple linear regressions analyses revealed that serum 25(OH)D concentration were not significant predictors of athletic performance in adolescent athletes. In conclusion, vitamin D status is weakly correlated with anaerobic capacity; moreover, the underlying mechanisms of how vitamin D influence anaerobic performance is unclear in the present study. Nevertheless, the importance of vitamin D on health benefits should not be underestimated, especially during growth periods.
本研究旨在探讨维生素 D 状态与青少年运动员运动表现和血液标志物的相关性。本横断面研究纳入了 47 名年龄在 15-18 岁的跆拳道运动员。运动表现采用最大摄氧量（VO）、无氧功率测试、垂直跳跃、敏捷 T 测试、下肢肌肉力量和疲劳抵抗进行评估。采集血液样本评估血清 25-羟维生素 D [25(OH)D]、游离睾酮、皮质醇、肌酸激酶和尿素。采用单因素方差分析（ANOVA），并使用 Bonferroni 调整的 α 水平（即 0.05/3）。采用多元线性回归分析以及 Pearson 和偏相关分析来检验 25(OH)D 浓度、运动表现和血液标志物之间的关系。参与者的 25(OH)D 浓度范围为 16-73.25 nmol/L，表明 74.5%的青少年运动员存在维生素 D 不足或缺乏。维生素 D 状态对运动表现因素或血液标志物均无显著影响。血清 25(OH)D 浓度与平均功率输出（r = 0.359， < 0.05）和相对平均功率输出（r = 0.325， < 0.05）呈正相关，调整骨龄、身高、体重、训练经验、瘦体重和体脂后。然而，25(OH)D 浓度与其他与运动表现相关的因素和血液标志物无关。此外，多元线性回归分析表明，血清 25(OH)D 浓度不是青少年运动员运动表现的显著预测因素。总之，维生素 D 状态与无氧能力呈弱相关；此外，在本研究中，维生素 D 影响无氧表现的潜在机制尚不清楚。然而，不应低估维生素 D 对健康益处的重要性，尤其是在生长期间。
