Adductor Injury Mitigation:
Lower extremity injuries are common among all levels and ages of tennis players. In fact, some reports suggest as much as 67% of all tennis injuries are lower extremity related (1). More specifically, adductor (groin) strains are listed as one of the most frequent injuries in elite junior tennis players (2,3). Adductor strains occur during movements involving quick acceleration or rapid change of direction when paired with extreme hip abduction, such as split type movements in which the leg moves away from the body, or also large hip external rotation. Combined injury of the hamstrings and hip adductor muscles – respectively, the semimembranosus, and adductor mangus and longus – has been observed during a split type movement in sports such as tennis (4). These movements happen most frequently on surfaces with less friction such as clay. Increased prevalence of adductor strains is often anecdotally associate with increased sliding side-to-side during play.
However, regardless of surface type, split type movements have become more prevalent in the modern game of tennis. This maneuver allows the player to retrieve balls hit a wide angle and also to preserve better positioning on the court to prepare the next shot. Additionally, open stance ground strokes are also more prevalent in the modern game of tennis. In both cases, the groin musculature undergoes extreme eccentric muscle actions (muscle lengthening under tension) to decelerate and control lateral momentum. Once the slide or open stance ground stroke is completed, the player typically incorporates a cross over recovery step via concentric adductor muscle action. These movements require adequate hip mobility, adductor flexibility and muscle function, where impairments in any one domain may increase risk of adductor strains.
Intrinsic Risk Factor:
A prospective study conducted by Tyler et al examined whether hip muscle strength and flexibility play a role in the incidence of adductor strains in NHL players (5). The authors measured preseason hip flexion, abduction and adduction strength in 47 players as well as adductor flexibility before two consecutive seasons. At the end of the second season, 11 adductor strains were reported in 8 players (indicating bilateral strains in some cases). Players who sustained an adductor strain were identified with 18% less preseason hip adduction strength compared with uninjured players. Also, adductor/abductor muscle ratios were significantly different as uninjured players demonstrated with adduction strength 95% of abduction strength vs. 78% of abduction strength in the injured players. Hip abductor flexibility and hip flexor strength had no association with injury. In summary, the authors’ concluded that players were 17 times more likely to sustain an adductor muscle strain if the adductor muscle strength was less than 80% of his abductor strength (5).
A study by Moreno-Perez et al investigated whether elite tennis players with a history of groin injury show differences in hip strength between injured and uninjured limbs, and also relative to the dominant limb in tennis players without history of acute groin-injuries. Similar to Tyler et al (5), adductor strength and adductor/abductor strength ratios were lower in the injured limb (16.4% and 20.1%, respectively) compared with uninjured limb, and additionally lower than the dominant limb of the injury-free group (6).
Injury mitigation/prevention:
A follow up study by Tyler et al in the same cohort of NHL players enrolled those at risk for adductor injury (adductor weakness and adductor/abductor strength ratio) in an adductor injury prevention program (7). The program consisted of 6 weeks of exercises aimed at strengthening the adductor muscles. Briefly, the program consisted of warm-up, strengthening and sports specific type exercises (Figure 1). The results revealed only three adductor strains in the 2 seasons subsequent to the intervention, vs 11 in the previous 2 seasons.
Single Best Adductor Injury Mitigation Exercise:
Numerous studies support Copenhagen Adduction Exercises as one of the single best exercise you can incorporate into your adductor injury prevention program. For example, a 2019 cluster-randomized control trial by Haroy et al evaluated the effectiveness of this exercise in 35 semi-professional soccer players (339 players total) on the prevalence of groin injury (8). The intervention group performed the Copenhagen Adduction Exercise three times per week during preseason and once per week during competitive season and the control group performed routine strengthening exercises. After the season commenced, the intervention group had 41% less groin injury incidence relative to the control group (8).
In summary, there is strong evidence in support of adductor strengthening for reducing injury to the adductor musculature. Players should properly prepare the adductor musculature routinely during preseason and competitive season via hip mobility exercise, dynamic warm-up, activation/strengthening based exercise, and functional/sports specific exercise prior to activity.
Take Away Points:
- There is strong evidence for adductor strengthening to reduce the risk of adductors strains.
- Adductor/abductor strength ratio should be at least 80% of abductor strength. Anything less than 80% may place the athlete at risk for adductor strains.
- Performing any variation of the Copenhagen Adduction Exercise will reduce the risk of injury to the adductors.
- Performing the Copenhagen Adduction Exercise at least 2-3 times per week during preseason and one time per week during competitive season may reduce risk of adductor strains.
- Adductor flexibility is not associated with injury. However, performing dynamic warm-up in conjunction with adductor strengthening may reduce the incidence of adductor strains.
- Previous history of groin strains may result in chronic weakness and may place the player at increased risk for adductor strains.
The program documented below is an effective routine I prescribe for my tennis players at the amateur and professional level. Add these exercises to your dynamic warm-up and exercise routine to increase strength, tissue extensibility and joint mobility.
Appendix 1: Adductor Muscle Strain Injury Prevention Program (Modified from (7) for Tennis
Tissue and Joint Preparation
These series of exercises are prescribed to increase tissue extensibility, improve arterial blood flow, decrease muscle soreness as well as elongation of the muscle under low load exercises.
- Foam rolling adductor 15-30 seconds
- Long Adductor rock back 1×10
- Quadruped Hip Circles 1×5 each way
- Supine leg whips 1×10
Movement Preparation (Dynamic Warm-Up) Adductor Bias
These lateral based movements are utilized to increase tissue temperature and extensibility by active elongation and loading.
- Lateral lunge side to sides
- Slide leg in front
- Side Kicks
- Carioca Cross-overs
- 3 step lunge with worlds greatest stretch
- Leg Swings
- Parameters:
- Perform these exercises from doubles line to doubles line.
Sports Specific Exercise
These exercises are incorporated to continue the process of increasing tissue temperature and active elongation with an emphasis on sport specific movements. These movements will help fine tune movement patterns utilized on court.
- Multi Directional Slider Lunges: Lateral and Posterior Lateral Sliders
- Open Stance Forehand and Backhand tosses Medicine Ball Toss
- If you do not have a partner, hold a medicine ball and repeat the same movements.
- Sets and Reps
- Warm-Up: 1 set 5-10 repetitions
- Strength Training: 2-3 sets 5-10 repetitions, will vary based athletes experience and goal of training that day.
Adductor Strengthening
Lastly, these exercises are prescribed to improve adductor muscle strength and endurance.
- Copenhagen Adduction Exercise (easiest to hardest)
- Variation 1: Side lying hip abduction
- Variation 2: Short adductor lever arm hip abduction
- Variation 3: Long adductor lever arm hip abduction
- Sets and Reps:
- 2 sets 10-15 repetitions
- Frequency:
- Preseason: 2-3 times per week
- Competitive Season: 1-2 times per week
Citations:
- Pluim, B. M., Staal, J. B., Windler, G. E., & Jayanthi, N. (2006). Tennis injuries: occurrence, aetiology, and prevention. British journal of sports medicine, 40(5), 415-423.
- Pluim, B. M., et al. “A one‐season prospective study of injuries and illness in elite junior tennis.” Scandinavian journal of medicine & science in sports 26.5 (2016): 564-571.
- Hutchinson, M. R., Laprade, R. F., Burnett, Q. M., Moss, R. O. B. E. R. T., & Terpstra, J. E. F. F. (1995). Injury surveillance at the USTA Boys’ Tennis Championships: a 6-yr study. Medicine and science in sports and exercise, 27(6), 826-831.
- Askling CM, Tengvar M, Saartok T, Thorstens- son A. Proximal hamstring strains of stretching type in different sports: injury situations, clinical & magnetic resonance imaging characteristics, & return to sport. Am J Sports Med. 2008
- Tyler, T. F., Nicholas, S. J., Campbell, R. J., & McHugh, M. P. (2001). The association of hip strength & flexibility with the incidence of adductor muscle strains in professional ice hockey players. The American journal of sports medicine, 29(2), 124-128.
- Moreno-Pérez, V., Lopez-Valenciano, A., Barbado, D., Moreside, J., Elvira, J. L. L., & Vera-Garcia, F. J. (2017). Comparisons of hip strength and countermovement jump height in elite tennis players with and without acute history of groin injuries. Musculoskeletal Science and Practice, 29, 144-149.
- Tyler, T. F., Nicholas, S. J., Campbell, R. J., Donellan, S., & McHugh, M. P. (2002). The effectiveness of a preseason exercise program to prevent adductor muscle strains in professional ice hockey players. The American journal of sports medicine, 30(5), 680-683.
- Harøy, J., Clarsen, B., Wiger, E. G., Øyen, M. G., Serner, A., Thorborg, K., … & Bahr, R. (2019). The Adductor Strengthening Programme prevents groin problems among male football players: a cluster-randomised controlled trial. Br J Sports Med, 53(3), 150-157.
