Authors: Tracey Wagner, Nazly Behnia, Won- Kay Lau Ancheta, Richard Shen, Shawn Farrokhi, Christopher M Powers

Journal of Orthopedic and Sport Physical Therapy, February 2010 volume 40, number 2

Commentary by Bruce Craven

Every High Performance Athlete is a “CASE STUDY”

When working with high performance athletes, we need to remember that most of these individuals do not fit within the normal population bell curve. This distribution becomes a problem when developing a treatment plan for them, as the majority of evidence based research for therapy intervention is based on normal individuals using parametric statistics. The plan that every therapist working with high performance athletes must remember, is to utilize evidence based research to create a theory behind the causative nature of the injury and then approach the athlete’s care like a case study. To complete the analysis and test the theoretical model that is directing the athletes’ treatment, it is imperative that the entire Integrated Support Team (IST) and Coach are involved in the process.

The researchers of this article have presented two possible causes for the exercise-associated cramping 1) electrolyte imbalance and 2) local muscle fatigue. Although each of these theories is unlikely to occur in isolation, it is important to involve all IST members with the development and testing of the treatment theories. The IST must dissect each theory to determine the appropriate causative factor. If there is not long-term success in management of the condition, the IST must accept the possibility of not identifying the correct etiology of the problem.

In this article, the athlete had been attempting to correct the problem through modification of training to address the muscle fatigue and correcting his electrolyte/nutrition status. There had been no long-term success in his treatment. Further investigation into the theory of isolated muscle fatigue must identify what muscles in the kinematic chain are fatiguing and what muscles over activated. To start this assessment, the athlete underwent the following:

• Clinical history of presenting condition

• Presenting complaints

• Medical Screening to rule out any “red flags” for major illnesses or conditions

• Differential diagnosis screening to localize the problem within the lower quadrant

• Clinical tests for flexibility, strength and motor function

• Dynamic Assessment looking at gait, and other movement tasks.

Following this assessment, it was determined that the athlete’s condition was consistent with the muscle fatigue theory. Further testing was required; as the assessment to date only identified that there was diminished hip extensor muscle performance. Although the manual muscle testing can not differentiate between the hamstring function and the gluteus maximus function in certain tasks, the testing provided insight into the dysfunction as there was excessive hip internal rotation and adduction during hip extension testing.

To further develop the causative theory the authors indicated that the gluteus maximus and hamstrings are agonist muscles during running. If the gluteus maximus was either weak or had impaired motor function, then the hamstrings would exert a greater effort during running causing it to fatigue earlier than it’s contralateral limb resulting in the cramping.

In this case, the athlete underwent a biomechanical evaluation of his running gait using EMG to differentiate the gluteus maximus and hamstring contribution during running. EMG found that the triathlete’s hamstring muscle was over activated during terminal swing and the first half of the stance phase during running. This supported the developed theory that the over-activation of the hamstrings may be causing the fatigue and resulting cramping.

The theoretical model implemented to guide the rehabilitation process; focused on the need to improve the gluteus maximus strength and neuromuscular control to provide better recruitment during terminal swing and the first half of stance. If the gluteus maximus improved its function during these phases of gait, the load requirement and resulting decrease in work done by the hamstrings would decrease the likelihood of muscle fatigue and the resulting cramping.

The physical therapy program consisted of strengthening and neuromuscular reeducation of the gluteus maximus, with exercises being progressed over 3 phases.

Phase One:

• non–weight-bearing exercises to emphasize isolated muscle recruitment

• exercises focused on muscle recruitment

• 3 sets of 8 to 15 repetitions were prescribed, with 1 to 2 minutes of rest between each set

Phase Two:

• weight-bearing exercises

• exercises focused on muscle hypertrophy

• 3 to 5 sets of 4 to 8 repetitions were prescribed, with 2 to 3 minutes of rest between each set.

Phase Three:

• dynamic and ballistic training

• exercises focused on muscle endurance

• 2 to 3 sets of 12 to 20 repetitions were prescribed, with 30 seconds to 3 minutes of rest between each set.

For each phase the exercises were performed on the right and left lower extremity.

During the 8 months of intervention, the athlete’s strength, dynamic control and hamstring and glut activation improved; allowing him to complete 3 half Ironman competitions without hamstring cramping issues. The case report supports the theory that improving strength and neuromuscular control of the gluteus maximus resulted in a decrease in hamstring activation during terminal swing and the first half of the stance phase during running. The authors caution the reader to take care in establishing cause and effect, based on a single case study.

This paper I feel guides us to an important reminder that when evaluating and treating our high performance athletes with chronic musculo-skeletal injuries. It is imperative that we develop a theoretical model to guide our treatment plan based on evidence based practice and to test this theory using the rigors of science from all members of the IST. As with every case study report, care must be taken in establishing cause and effect, based on a single patient; however, it is also important to remember that in high performance sport there is very little evidence to support cause and effect when it comes to a successful performance.