How the Copenhagen Adductor Exercise Prevents Groin Injuries: What the Research Shows

Groin injuries are one of the most persistent problems in football, keeping players off the field for weeks at a time and returning at frustratingly high rates. Despite how common these injuries are, prevention strategies have historically received far less attention than hamstring or knee injury programs. A cluster-randomised trial published in the British Journal of Sports Medicine set out to change that by testing whether a structured adductor strengthening program could meaningfully reduce groin problems in male football players. The results offer a compelling case for making targeted hip adductor work a regular part of any football training routine — and the lessons apply well beyond the pitch.

What This Study Examined

The central question of this research was straightforward: can a targeted adductor strengthening program reduce the incidence of groin problems in male football players?

Groin injuries in football are largely driven by weakness or imbalance in the hip adductor muscles — the muscles on the inner thigh responsible for pulling the legs toward the midline. These muscles are heavily loaded during kicking, cutting, and rapid changes of direction. Researchers wanted to understand whether proactively strengthening this muscle group, using an exercise called the Copenhagen Adductor exercise, could serve as an effective preventive intervention during a competitive season.

The study examined both the rate of groin problems and the severity of those problems, giving a more complete picture of injury burden rather than just counting individual incidents.

How the Study Was Conducted

The study used a cluster-randomised trial design, which means football clubs — rather than individual players — were randomly assigned to either an intervention group or a control group. This design is commonly used in sports injury research because players on the same team share training environments and cannot be treated as fully independent from one another.

Male football players from multiple clubs participated in the trial. Clubs in the intervention group completed the Adductor Strengthening Programme, which was built around the Copenhagen Adductor exercise. In this exercise, a player lies on their side while a partner holds their top leg elevated. The player then lifts their bottom leg up to meet the top leg using adductor strength. It is a relatively simple exercise to perform but places a significant eccentric and isometric load on the inner thigh muscles.

The program was delivered as a structured, progressive protocol integrated into the clubs' existing training sessions. Clubs in the control group continued their normal training without the adductor program.

The researchers tracked groin problems throughout the football season, recording both the number of players who experienced groin issues and the time lost from training and match play as a result.

Key Findings

The study found that the Adductor Strengthening Programme had a meaningful effect on reducing groin problems among players who completed it. Specifically:

• Players in the intervention group experienced substantially fewer groin problems compared to players in the control group.

• The program appeared to reduce both the number of groin injuries and the overall burden those injuries placed on teams across the season.

• The results suggest that the Copenhagen Adductor exercise, when performed consistently as part of a structured program, can serve as an effective preventive tool.

• Compliance with the program was an important factor — the protective effect was more evident in players who adhered to the protocol.

The researchers observed these outcomes across a competitive season, suggesting the program is practical enough to be implemented in real-world training environments without significantly disrupting existing schedules.

What This Means for Training

Taken together, these findings suggest that proactive adductor strengthening should be considered a standard component of injury prevention for football players, much the same way the Nordic Hamstring exercise has become widely adopted for hamstring health. You can read more about that in our article on how Nordic Hamstring exercises reduce hamstring injuries.

For coaches and athletes, the practical takeaway is that the Copenhagen Adductor exercise does not require expensive equipment or significant time investment. It can be programmed into warm-ups or supplementary work a few times per week. The exercise challenges the adductors under load — particularly in their lengthened position — which appears to build the kind of resilience these muscles need to withstand the demands of football.

It is also worth noting that groin injuries are not exclusive to elite players. Recreational and amateur athletes who play football, hockey, basketball, or other multidirectional sports place similar demands on the hip adductors. While this study focused on male football players specifically, the underlying principle — that strengthening a vulnerable muscle group reduces the likelihood of injury — is a well-established concept in sports medicine.

For anyone training under a structured program, whether in-person or through online personal training, these findings reinforce the importance of including often-neglected muscle groups like the adductors in a well-rounded resistance training plan. Working with a qualified coach who understands evidence-based injury prevention can help ensure these types of exercises are programmed correctly and progressed appropriately over time.

Limitations of the Study

As with any research, it is important to consider what the study does not tell us:

• The study focused exclusively on male football players, so the findings cannot be automatically extended to female athletes or athletes in other sports without additional research.

• Compliance varied across clubs, and the degree of benefit appeared linked to how consistently players completed the program. In real-world settings, adherence can be difficult to maintain across a full season.

• Cluster randomisation, while appropriate for this type of study, means that differences between clubs — such as coaching quality, training load, or pitch conditions — could influence results in ways that are difficult to fully control for.

• The study examined groin problems broadly, and individual injury mechanisms can vary, meaning the program may address some causes of groin pain more effectively than others.

These limitations do not undermine the findings, but they are a reminder that no single study provides the final word on any topic.

Conclusion

The research on the Adductor Strengthening Programme adds meaningful evidence to the growing field of injury prevention in football. The study found that a structured program built around the Copenhagen Adductor exercise was associated with a notable reduction in groin problems across a competitive season — a finding with real practical value for coaches, medical staff, and athletes alike.

Groin injuries are both common and costly in terms of playing time lost, and this research suggests a relatively simple exercise protocol may help reduce that burden. Just as evidence has shaped how coaches use the Nordic Hamstring exercise or plyometric training for speed and jump performance, research like this helps inform how thoughtful coaches structure resistance and injury prevention programs for their athletes.

If you are looking to build a more complete, evidence-informed training program — whether you play football or simply want to move better and reduce injury risk — the coaches at Atlas Personal Training in Reno can help you put these principles into practice.

Related Articles

• How Nordic Hamstring Exercises Reduce Hamstring Injuries

• Why Nordic Hamstring Exercises Reduce Hamstring Injuries

• Plyometric Training for Speed and Jump Performance in Soccer

Source

Harøy J, Clarsen B, Wiger EG, et al. The Adductor Strengthening Programme prevents groin problems among male football players: a cluster-randomised trial. British Journal of Sports Medicine. 2019.

Research Source: The Adductor Strengthening Programme prevents groin problems among male football players: a cluster-randomised trial