Hsueh Chang-Li, Sun Cheng-Yen, Chang Chen-Kang
National Taiwan University of Sport, Department of Sport Performance, Taichung, Taiwan.
Chang Jung Christian University, Department of Athletic Sports, Tainan, Taiwan.
J Int Soc Sports Nutr. 2025 Dec;22(1):2441763. doi: 10.1080/15502783.2024.2441763. Epub 2024 Dec 16.
Rugby sevens is a high-intensity contact sport often played in two-day tournaments. Caffeine is widely used by rugby players for its performance-enhancing effects. This study aimed to investigate the impact of caffeine supplementation on various performance metrics, including distance covered at different speeds, acceleration, deceleration, collisions, and repeated high-intensity efforts across four matches over two consecutive days in collegiate male rugby sevens players. Reactive agility, a key performance attribute in rugby sevens, was also assessed before each match.
A position-matched, double-blind, randomized crossover design was employed, with six male collegiate rugby players (mean height: 1.78 ± 0.09 m, mean weight: 81.3 ± 9.2 kg, mean age: 21.5 ± 0.8 years) participating in two trials. Each trial consisted of a two-day tournament, with two matches per day. Performance was monitored using global positioning system units to track distance covered in various speed zones, as well as total distance, frequency of acceleration, deceleration, collisions, and repeated high-intensity efforts.
The results indicated that in the placebo trial, participants covered significantly more distance at a walking pace (0-6 km/h) in match 4 compared to match 3 (match 3: 480.3 ± 32.7 m; match 4: 629.4 ± 21.3 m, < 0.001, d = 0.117). In the caffeine trial, players covered significantly more distance at a jogging pace (6-12 km/h) in match 4 compared to the placebo trial (caffeine: 405.9 ± 9.8 m; placebo: 303.6 ± 20.2 m, = 0.015, d = 1.693). Reactive agility was significantly better in the caffeine trial before match 3 (caffeine trial: 1.80 ± 0.17 s; placebo trial: 2.07 ± 0.18 s, = 0.038, d = 0.858).
Caffeine supplementation at 3 mg/kg may increase jogging and reduce walking and standing in the final match of a two-day rugby sevens tournament, while also improving reactive agility on the second day. This suggests that by mitigating fatigue in the later stages of the tournament, caffeine allowed players to shift from low-intensity activities to higher-intensity efforts. These adjustments may improve both offensive and defensive performance during rugby sevens matches. Therefore, rugby sevens players could benefit from taking caffeine supplements in the later stages of 2-day tournaments to optimize their performance.
七人制橄榄球是一项高强度的接触性运动,通常在为期两天的锦标赛中进行。咖啡因因其增强运动表现的作用而被橄榄球运动员广泛使用。本研究旨在调查补充咖啡因对各项运动表现指标的影响,包括不同速度下的跑动距离、加速、减速、碰撞以及连续两天四场比赛中的重复高强度运动。七人制橄榄球的一项关键运动表现属性——反应敏捷性,也在每场比赛前进行了评估。
采用位置匹配、双盲、随机交叉设计,六名男性大学七人制橄榄球运动员(平均身高:1.78±0.09米,平均体重:81.3±9.2千克,平均年龄:21.5±0.8岁)参与两项试验。每项试验包括为期两天的锦标赛,每天两场比赛。使用全球定位系统设备监测运动表现,以追踪不同速度区域的跑动距离、总距离、加速频率、减速频率、碰撞次数以及重复高强度运动次数。
结果表明,在安慰剂试验中,与第3场比赛相比,参与者在第4场比赛中以步行速度(0 - 6千米/小时)跑动的距离显著增加(第3场比赛:480.3±32.7米;第4场比赛:629.4±21.3米,<0.001,d = 0.117)。在咖啡因试验中,与安慰剂试验相比,球员在第4场比赛中以慢跑速度(6 - 12千米/小时)跑动的距离显著增加(咖啡因组:405.9±9.8米;安慰剂组:303.6±20.2米, = 0.015,d = 1.693)。在第3场比赛前的咖啡因试验中,反应敏捷性显著更好(咖啡因试验:1.80±0.17秒;安慰剂试验:2.07±0.18秒, = 0.038,d = 0.858)。
在为期两天的七人制橄榄球锦标赛的最后一场比赛中,每千克体重补充3毫克咖啡因可能会增加慢跑距离,减少步行和站立时间,同时还能提高第二天的反应敏捷性。这表明,通过减轻比赛后期的疲劳,咖啡因使球员能够从低强度活动转向更高强度的运动。这些调整可能会提高七人制橄榄球比赛中的进攻和防守表现。因此,七人制橄榄球运动员在为期两天的锦标赛后期服用咖啡因补充剂可能会优化他们的表现。