METHODS: Participants were 19 women, aged 22.9 ± 4.2 years, with body mass index 18-30 kg·m2. They were divided into two groups and completed two conditions in a crossover design: a 3-day control condition (CON) with an energy availability of 45 kcals·kgFFM-1·day-1 and a 3-day LEA condition of 15 kcals·kgFFM-1 day-1. Assessments were conducted during the early follicular phase of the menstrual cycle. Outcome measures included forearm blood flow (FBF), heart rate, blood pressure, arterial stiffness, resting energy expenditure (REE), metabolic blood markers and body composition.
RESULTS: Significant time-by-condition interactions were found for resting FBF (p = .004), REE (p = .042), triiodothyronine (p = .006), β-hydroxybutyrate (p = .002) and body mass (p < .001). Resting FBF was 1.43 ± 1.01 and 1.31 ± 0.61 (arbitrary units) at pre and post, respectively, in LEA and 1.52 ± 0.7 and 1.76 ± 0.57 at pre and post in CON. The LEA condition led to a decrease in triiodothyronine (pre: 1.54 ± 0.28, post: 1.29 ± 0.27 ng ml-1), REE (pre: 1588 ± 165, post: 1487 ± 160 kcals day-1) and body mass (pre: 61.4 ± 7.5, post: 59.6 ± 7.3 kg). Changes in resting FBF were significantly correlated with changes in REE in the LEA condition (r = 0.53; p = 0.02).
CONCLUSIONS: Short-term LEA modifies regional blood flow and this might contribute to the observed decreased in REE. Findings emphasize the need for careful management of energy availability in populations at risk of LEA.
方法:参与者为19名女性,年龄22.9±4.2岁,体重指数为18-30kg·m2。他们分为两组,并在交叉设计中完成了两个条件:3天控制条件(CON),能量可用性为45kcals·kgFFM-1·day-1,3天LEA条件为15kcals·kgFFM-1day-1。在月经周期的早期卵泡期进行评估。结果测量包括前臂血流量(FBF),心率,血压,动脉僵硬度,静息能量消耗(REE),代谢血液标志物和身体成分。
结果:发现静息FBF的显着时间-条件相互作用(p=.004),REE(p=.042),三碘甲状腺原氨酸(p=.006),β-羟基丁酸酯(p=0.002)和体重(p<.001)。静息FBF前后分别为1.43±1.01和1.31±0.61(任意单位),分别,LEA和CON前后的1.52±0.7和1.76±0.57。LEA条件导致三碘甲状腺原氨酸减少(前:1.54±0.28,后:1.29±0.27ngml-1),REE(前:1588±165,后:1487±160kcalsday-1)和体重(前:61.4±7.5,后:59.6±7.3kg)。在LEA条件下,静息FBF的变化与REE的变化显着相关(r=0.53;p=0.02)。
结论:短期LEA改变局部血流,这可能有助于观察到的REE降低。研究结果强调,需要认真管理存在LEA风险的人群的能源可用性。