New research published in the Journal of the International Society of Sports Nutrition suggests that caffeine supplementation may help male collegiate rugby sevens players sustain their activity levels and improve agility during two-day tournaments. Players who consumed caffeine before matches covered more distance at jogging speeds in the final match, while those without caffeine tended to slow down, spending more time standing and walking. The study also found that caffeine improved players’ reactive agility on the second day, suggesting a potential role in reducing fatigue-related declines in performance.
Rugby sevens is an intense sport that requires repeated bursts of high-speed running, rapid changes in direction, and physical contact, all within a tournament format that demands multiple matches over two consecutive days. Given these physical and psychological demands, researchers have explored different strategies to help athletes maintain performance and recover effectively.
Caffeine is one of the most widely used performance-enhancing substances in sports. Previous studies have shown that caffeine can improve endurance, power output, and sprint performance in team sports. However, most research has focused on single matches rather than tournaments spanning multiple days.
“Rugby sevens is an official competition in the Asian Games and the Olympics. It is also popular in worldwide tours. Rugby sevens requires high-intensity efforts and quick recovery between matches,” explained lead author Chen-Kang Chang, a professor of sport performance at the National Taiwan University of Sport.
“A tournament usually includes four to seven matches in two consecutive days, which places high physiological and psychological demands on players. As a sports scientist, we try to find ways, including supplements, to facilitate performance and recovery. As an active rugby player, this topic fits well with my work and passion for this sport.”
The study used a double-blind, randomized crossover design, meaning neither the participants nor the researchers knew who was receiving caffeine or a placebo during each trial. Eight collegiate male rugby players were recruited, with six completing the full study. Each player participated in two tournaments, one with caffeine supplementation and one with a placebo, with a 13-day break in between.
Players consumed 3 mg of caffeine per kilogram of body weight 60 minutes before each match during the caffeine trial. In the placebo trial, they received an identical-looking capsule containing starch. Both trials followed the same structured diet, hydration plan, and match schedule to minimize differences outside of caffeine intake.
Each tournament involved four matches over two days, with two matches per day. Players wore GPS tracking devices to measure their movement patterns, including total distance covered, time spent at different speeds, acceleration, deceleration, and collisions. Before each match, a reactive agility test was conducted to assess their ability to change direction quickly in response to an unpredictable stimulus.
The study’s key finding was that caffeine supplementation influenced how players distributed their physical effort across the tournament. On the second day, players who consumed caffeine before their final match spent less time standing and walking and more time jogging (6–12 km/h), whereas players in the placebo trial showed the opposite trend. This suggests that caffeine helped sustain players’ ability to engage in moderate-intensity activity when fatigue typically sets in.
The results also showed that caffeine enhanced reactive agility before the first match on the second day. Players in the caffeine trial responded faster in the agility test compared to those in the placebo trial, potentially giving them a competitive edge in real-game situations that require quick decision-making and rapid directional changes.
“For average rugby players, consuming supplements or drinks that contain 3 mg/kg body weight of caffeine before matches may help performance, especially in multiple competitions over one or two days,” Chang told PsyPost. “For the average person who is interested in other sports, caffeine has been shown to improve performance in endurance or short-term high-intensity exercise.”
Interestingly, caffeine did not significantly affect high-intensity efforts such as sprinting, collisions, or repeated bursts of acceleration and deceleration. This indicates that while caffeine helped players stay more active during lower-intensity periods, it did not directly increase their ability to perform the most physically demanding actions of the game.
“We hypothesized that caffeine could improve distance in high-speed ranges such as 18–20 km/h or greater than 20 km/h,” Chang noted. “Instead, the results showed that the differences were in walking and jogging. We were a little disappointed that caffeine had no effect on acceleration, deceleration, or collisions.”
As with all research, there are some limitations. The sample size was small due to the nature of rugby sevens, where each match involves a limited number of players. Additionally, movement patterns can be influenced by tactical decisions, errors, and game dynamics, making it difficult to isolate the effects of caffeine from other factors.
Future research should focus on larger sample sizes, particularly among elite players in international competitions. Long-term studies could also track caffeine’s effects across a full season, especially when athletes travel across multiple time zones. Another area of interest is whether substituted players, who play fewer minutes, can benefit from caffeine in the same way as those who play full matches.
“We hope to collect data from elite rugby players with larger sample sizes, preferably in international competitions,” Chang explained. “Long-term monitoring of elite players across a competitive season, especially when they have to travel across multiple time zones within weeks, should make the findings more applicable to real competitions. We would also like to investigate whether substituted players, who play fewer minutes in a match, can benefit from caffeine supplementation.”
“Field studies like this have limitations compared to lab-based controlled exercise performance evaluations. The results can vary match by match, making them difficult to interpret. However, this design more closely reflects real match competitions.”
The study, “Caffeine supplementation improved movement patterns and reactive agility in rugby sevens matches in male collegiate players,” was authored by Chang-Li Hsueh, Cheng-Yen Sun, and Chen-Kang Chang.
