PDF(Pubmed)
Abstract：
BACKGROUND: The sleep-low method has been proposed as a way to sleep in a low-glycogen state, increase the duration of low glycogen availability and sleep and temporarily restrict carbohydrates to improve exercise performance. However, long-term dietary restriction may induce mental stress in athletes. Therefore, if it can be shown that the effects of the sleep-low method can be achieved by restricting the carbohydrate intake at night (the nighttime carbohydrate restriction method), innovative methods could be developed to reduce weight in individuals with obesity and enhance athletes\' performance with reduced stress and in a shorter duration when compared with those of previous studies. With this background, we conducted a study with the purpose of examining the intervention effects of a short-term intensive nighttime carbohydrate restriction method.
METHODS: A total of 22 participants were recruited among university students participating in sports club activities. The participants were assigned at random to groups, including a nighttime carbohydrate restriction group of 11 participants (6 males, 5 females; age 22.3 ± 1.23) who started a carbohydrate-restricted diet and a group of 11 participants (5 males, 6 females; age 21.9 ± 7.9) who continued with their usual diet. The present study had a two-group parallel design. In the first week, no dietary restrictions were imposed on either group, and the participants consumed their own habitual diets. In the second week, the total amount of calories and carbohydrate intake measured in the first week were divided by seven days, and the average values were calculated. These were used as the daily calorie and carbohydrate intakes in the second week. Only the nighttime carbohydrate restriction group was prohibited from consuming carbohydrates after 4:00 p.m. During the two-week study period, all participants ran for one hour each day before breakfast at a heart rate of 65% of their maximum heart rate.
RESULTS: The results obtained from young adults participating in sports showed significant differences in peak oxygen consumption (V·O2peak), work rate max, respiratory quotient (RQ), body weight and lean body mass after the intervention when compared with before the intervention in the nighttime carbohydrate restriction group (p < 0.05).
CONCLUSIONS: Our findings suggest that the nighttime carbohydrate restriction method markedly improves fat metabolism even when performed for a short period. This method can be used to reduce body weight in individuals with obesity and enhance athletes\' performance. However, it is important to consider the intake of nutrition other than carbohydrates.
METHODS: A total of 22 participants were recruited among university students participating in sports club activities. The participants were assigned at random to groups, including a nighttime carbohydrate restriction group of 11 participants (6 males, 5 females; age 22.3 ± 1.23) who started a carbohydrate-restricted diet and a group of 11 participants (5 males, 6 females; age 21.9 ± 7.9) who continued with their usual diet. The present study had a two-group parallel design. In the first week, no dietary restrictions were imposed on either group, and the participants consumed their own habitual diets. In the second week, the total amount of calories and carbohydrate intake measured in the first week were divided by seven days, and the average values were calculated. These were used as the daily calorie and carbohydrate intakes in the second week. Only the nighttime carbohydrate restriction group was prohibited from consuming carbohydrates after 4:00 p.m. During the two-week study period, all participants ran for one hour each day before breakfast at a heart rate of 65% of their maximum heart rate.
RESULTS: The results obtained from young adults participating in sports showed significant differences in peak oxygen consumption (V·O2peak), work rate max, respiratory quotient (RQ), body weight and lean body mass after the intervention when compared with before the intervention in the nighttime carbohydrate restriction group (p < 0.05).
CONCLUSIONS: Our findings suggest that the nighttime carbohydrate restriction method markedly improves fat metabolism even when performed for a short period. This method can be used to reduce body weight in individuals with obesity and enhance athletes\' performance. However, it is important to consider the intake of nutrition other than carbohydrates.
摘要：
背景：已提出将低睡眠方法作为在低糖原状态下睡眠的一种方法，增加低糖原可用性和睡眠的持续时间，并暂时限制碳水化合物以改善运动表现。然而,长期饮食限制可能会引起运动员的精神压力。因此,如果可以证明可以通过限制夜间碳水化合物的摄入量（夜间碳水化合物限制方法）来实现低睡眠方法的效果，与以前的研究相比，可以开发创新的方法来减轻肥胖个体的体重，并在减少压力和更短的持续时间内提高运动员的表现。在这样的背景下,我们进行了一项研究，目的是检查短期强化夜间碳水化合物限制方法的干预效果。
方法：在参加体育俱乐部活动的大学生中招募22名参与者。参与者被随机分组，包括一个由11名参与者组成的夜间碳水化合物限制组(6名男性，5名女性；年龄22.3±1.23），开始碳水化合物限制饮食和一组11名参与者（5名男性，6名女性；年龄21.9±7.9），继续常规饮食。本研究采用两组并行设计。在第一周,两组都没有饮食限制，参与者消耗自己的习惯性饮食。第二周,第一周测量的卡路里和碳水化合物摄入量的总量除以七天，并计算平均值。这些被用作第二周的每日卡路里和碳水化合物摄入量。在为期两周的研究期间，只有夜间限制碳水化合物组被禁止在下午4:00后摄入碳水化合物，所有参与者每天早餐前跑一小时,心率为最大心率的65%.
结果：从参加运动的年轻人获得的结果显示，峰值耗氧量（V·O2峰值）存在显着差异，最大工作速率,呼吸商（RQ），夜间碳水化合物限制组干预后的体重和瘦体重与干预前比较（p<0.05）。
结论：我们的发现表明，夜间碳水化合物限制方法即使在短时间内也能显著改善脂肪代谢。该方法可用于减轻肥胖个体的体重并提高运动员的表现。然而,重要的是要考虑碳水化合物以外的营养摄入量。
方法：在参加体育俱乐部活动的大学生中招募22名参与者。参与者被随机分组，包括一个由11名参与者组成的夜间碳水化合物限制组(6名男性，5名女性；年龄22.3±1.23），开始碳水化合物限制饮食和一组11名参与者（5名男性，6名女性；年龄21.9±7.9），继续常规饮食。本研究采用两组并行设计。在第一周,两组都没有饮食限制，参与者消耗自己的习惯性饮食。第二周,第一周测量的卡路里和碳水化合物摄入量的总量除以七天，并计算平均值。这些被用作第二周的每日卡路里和碳水化合物摄入量。在为期两周的研究期间，只有夜间限制碳水化合物组被禁止在下午4:00后摄入碳水化合物，所有参与者每天早餐前跑一小时,心率为最大心率的65%.
结果：从参加运动的年轻人获得的结果显示，峰值耗氧量（V·O2峰值）存在显着差异，最大工作速率,呼吸商（RQ），夜间碳水化合物限制组干预后的体重和瘦体重与干预前比较（p<0.05）。
结论：我们的发现表明，夜间碳水化合物限制方法即使在短时间内也能显著改善脂肪代谢。该方法可用于减轻肥胖个体的体重并提高运动员的表现。然而,重要的是要考虑碳水化合物以外的营养摄入量。
