Koehler Karsten, Achtzehn Silvia, Braun Hans, Mester Joachim, Schaenzer Wilhelm
Institute of Biochemistry, German Sport University, Am Sportpark Muengersdorf 6, D-50933 Cologne, Germany.
Appl Physiol Nutr Metab. 2013 Jul;38(7):725-33. doi: 10.1139/apnm-2012-0373. Epub 2013 Jan 30.
Previous intervention studies suggest that leptin, insulin, insulin-like growth factor 1 (IGF-1), and triiodthyronine (T3) are sensitive markers of inadequate energy intake in relation to exercise expenditures. Because of limitations in metabolic hormone measurements, self-reported energy availability (EA) based on food and activity records may present an alternative for characterizing energy status in young athletes. The purpose of the current study was to assess whether self-reported EA is related to leptin, insulin, IGF-1, and T3 in 352 young athletes. Sex, body composition, sport participation, and acute weight changes were considered as confounding variables. Multiple linear regression revealed that EA was negatively associated with leptin (p < 0.05) but not with insulin, IGF-1, or T3. Female athletes with low EA (<30 kcal·kg(-1) fat-free mass (FFM)) had higher leptin concentrations (5.0 ± 4.7 ng·mL(-1)) and more body fat (18.3% ± 5.1%) than did females with normal EA (leptin, 3.1 ± 2.4 ng·mL(-1); body fat, 15.8% ± 4.2%; both, p < 0.001). Athletes reporting acute weight loss (>1 kg·week(-1)) had a lower EA (18.9 ± 7.4 kcal·kg(-1) FFM) than did weight-stable athletes (30.0 ± 11.2 kcal·kg(-1) FFM) or athletes reporting weight gain (>1 kg; 49.7 ± 13.1 kcal·kg(-1) FFM). IGF-1 and T3 were also reduced in athletes who lost weight (p < 0.01). This cross-sectional study reveals a lack of association between self-reported EA and metabolic hormones indicative of energy status in young athletes. Further studies are needed to investigate whether self-reported EA and metabolic hormones are in better agreement when measured repeatedly.
以往的干预研究表明，瘦素、胰岛素、胰岛素样生长因子1（IGF-1）和三碘甲状腺原氨酸（T3）是与运动消耗相关的能量摄入不足的敏感标志物。由于代谢激素测量存在局限性，基于食物和活动记录的自我报告能量可利用性（EA）可能是一种表征年轻运动员能量状态的替代方法。本研究的目的是评估352名年轻运动员中自我报告的EA是否与瘦素、胰岛素、IGF-1和T3相关。性别、身体成分、运动参与情况和急性体重变化被视为混杂变量。多元线性回归显示，EA与瘦素呈负相关（p<0.05），但与胰岛素、IGF-1或T3无关。与正常EA的女性运动员（瘦素，3.1±2.4 ng·mL-1；体脂，15.8%±4.2%；两者，p<0.001）相比，EA较低（<30 kcal·kg-1去脂体重（FFM））的女性运动员瘦素浓度更高（5.0±4.7 ng·mL-1）且体脂更多（18.3%±5.1%）。报告急性体重减轻（>1 kg·周-1）的运动员的EA（18.9±7.4 kcal·kg-1 FFM）低于体重稳定的运动员（30.0±11.2 kcal·kg-1 FFM）或报告体重增加（>1 kg；49.7±13.1 kcal·kg-1 FFM）的运动员。体重减轻的运动员的IGF-1和T3也降低了（p<0.01）。这项横断面研究揭示了年轻运动员中自我报告的EA与指示能量状态的代谢激素之间缺乏关联。需要进一步研究来调查重复测量时自我报告的EA和代谢激素是否更一致。
