Department of Life Sciences, University of Nicosia, 46 Makedonitisas Avenue, CY 1700, Nicosia, Cyprus.
Research Centre for Exercise and Nutrition (RECEN), Nicosia, Cyprus.
Eur J Nutr. 2024 Nov 25;64(1):23. doi: 10.1007/s00394-024-03540-6.
To assess the effects of carbohydrate timing and type on body composition and physical fitness.
Forty-two healthy, trained male volunteers underwent a four-week intervention, randomly divided into three groups: (i) Sleep Low-No Carbohydrates (SL-NCHO): consuming all carbohydrate intake at regular intervals prior to evening training, (ii) Sleep High-Low Glycemic Index (SH-LGI), and (iii) Sleep High-High Glycemic Index (SH-HGI). In both SH-LGI and SH-HGI, carbohydrates were distributed throughout the day, both pre-(60% of total intake) and post-evening training (40% of total intake). The SH-LGI and SH-HGI groups diverged in evening carbohydrate quality, featuring LGI and HGI foods, respectively. All participants performed a standardized exercise program combining resistance exercise and high-intensity interval training. Body composition was assessed using skinfold measurements and bioelectrical impendence analysis. Physical fitness was assessed by measuring VOmax, Visual Reaction Time (VRT), Countermovement Jump (CMJ), and 1-repetition maximum (1RM) in hack squat, chest press, shoulder press, and lat-pulldown exercises.
There was a significant time-effect on both body composition and physical fitness indices. Bodyfat percentage decreased by an average of 1.5% (p < 0.001), fat-mass by 1.4 kg (p < 0.001) and fat-free mass increased by 0.9 kg (p = 0.006). A time-effect was also observed in VOmax, CMJ, 1RM testing, and VRT (all p < 0.05). There were no significant differences among interventions.
A balanced dietary plan with sufficient nutrient and energy intake promotes body composition optimization and physical fitness, independently of carbohydrate type or timing. This study points towards implementing flexible nutrition interventions, emphasizing the potential of tailored dietary strategies to optimize health and physical fitness.
The trial was registered at clinicaltrials.gov as NCT05464342.
评估碳水化合物的时间和类型对身体成分和身体健康的影响。
42 名健康、训练有素的男性志愿者进行了为期四周的干预，随机分为三组：（i）睡眠低-无碳水化合物（SL-NCHO）：在晚上训练前的常规时间间隔内摄入所有碳水化合物，（ii）睡眠高-低血糖指数（SH-LGI），和（iii）睡眠高-高血糖指数（SH-HGI）。在 SH-LGI 和 SH-HGI 中，碳水化合物全天分布，包括训练前（总摄入量的 60%）和晚上训练后（总摄入量的 40%）。SH-LGI 和 SH-HGI 组在晚上碳水化合物的质量上存在差异，分别为低血糖指数和高血糖指数的食物。所有参与者都进行了一项结合阻力运动和高强度间歇训练的标准化运动计划。身体成分通过皮褶测量和生物电阻抗分析进行评估。通过测量 VOmax、视觉反应时间（VRT）、下蹲跳（CMJ）和 1 次重复最大重量（1RM）在深蹲、卧推、肩推和背阔肌下拉练习中评估身体健康。
身体成分和身体健康指数都有显著的时间效应。体脂百分比平均下降 1.5%（p<0.001），脂肪质量下降 1.4 公斤（p<0.001），瘦体重增加 0.9 公斤（p=0.006）。VOmax、CMJ、1RM 测试和 VRT 也观察到时间效应（均 p<0.05）。各组间无显著差异。
平衡的饮食计划，提供足够的营养和能量摄入，促进身体成分优化和身体健康，独立于碳水化合物的类型或时间。这项研究表明实施灵活的营养干预措施，强调了定制饮食策略优化健康和身体健康的潜力。
该试验在 clinicaltrials.gov 上注册为 NCT05464342。
