Research in sevens

To date, research focus on Sevens has been on the elite level of the sport. Investigators have identified key determinants of performance,1 the match demands of Sevens,2 the effects of fatigue on performance and recovery,3 ,4 and strategies to optimise playing performance, preparation and recovery between matches.5 ,6

There is also a research focus on injury epidemiology and prevention. This has been largely directed towards the elite game, due to the accessibility of cohorts (national teams participating in the men's and women's World Rugby Sevens Series tournaments), and in part due to the relative logistical ease of capturing quality injury and match/practice exposure data from elite teams in professional environments.

Key discoveries

Injury research on the elite Sevens game has found that both incidence and severity are greater than that of elite 15-a-side Rugby Union. In Sevens, injury incidence is 109 injuries/1000 h, compared to 89 injuries/1000 h in the 15-a-side game.7 ,8 Injury severity is significantly greater in Sevens (45 days vs 24 days for Sevens and Fifteens, respectively)7 ,8 resulting in a significantly greater total burden of injury for Sevens.

Other research with applications for player welfare involves considerations of travel burdens and the cumulative fatigue that accrues over a season.4 ,6 Men's International Sevens is played in a calendar consisting of 10 tournaments, divided into 5 legs of 2 tournaments each. Tournaments are generally 2 days long, with up to three matches played per day, with approximately 3 h recovery between matches. Women play a similar schedule, though currently with 5 tournaments rather than 10.

The challenge for conditioning coaches and medical personnel is to prepare players for this repeat-bout exposure, and to maximise recovery at four levels—from one leg to the next, typically 4–6 weeks in duration; from one tournament to the next, a duration of 1 week; from 1 day to the next within each tournament; and from one match to the next, a maximum of 3 h.

There was significant fatigue-induced decrement in both performance ability and neuromuscular function. Suarez-Arrones3 found a significant reduction in distance covered, as well as in the number of accelerations and sprints attempted in the second half of matches compared to the first. This fatigue persists, with neuromuscular impairments observed for at least a week after tournament play.6 Jump height decreased by 6%, and then remained impaired for the entire week, such that indices of neuromuscular function are suppressed at the start of the second tournament a week later.6

Given the recent finding that fatigue may significantly increase injury risk,8 strategies to minimise this neuromuscular impairment are particularly critical. This is an area that remains under-researched.

As described, the injury burden of elite Sevens is significantly greater than that of 15-player Rugby Union. Whether this phenomenon is also present at lower levels of the sport is unknown and questionable—injury risk decreases with performance level in the 15-player version of Rugby Union, but no data exist on injury epidemiology for Sevens beneath the professional game.

In Sevens, Ross et al 2 compared match demands of international (elite) and Provincial (sub-elite) Rugby Sevens. International matches have greater ball in play time, and international players covered greater distances at higher speeds, performed significantly more sprints than provincial players2 and also executed a similar number of tackles, which have been documented as the event responsible for most injuries.8

Given that the speed and thus potentially the impact forces in the tackle are lower in the sub-elite game, it seems reasonable to suggest that community sevens will have a reduced risk of injury. However, it must also be acknowledged that conditioning at lower levels of participation is likely to lag behind that of the professional game, and it is the balance between conditioning and match demands that may influence overall injury risk. In this regard, injury prevention strategies may become increasingly important to the successful growth of the sport amid concerns over injury risks.

In conclusion, as Rugby Sevens makes its first Olympic appearance, it ushers in an important and expanding area of research across both traditional and ‘non-traditional’ rugby communities.