This study was supported in part by the School of Health Related Professions Research and Development Fund, University of Pittsburgh, Pittsburgh, PA

A common complaint of competitive swimmers is shoulder pain. The purposes of this study were to: 1) provide normative data on shoulder flexibility in swimmers, 2) determine if a correlation exists between flexibility and shoulder pain, and 3) determine the correlation between strength and endurance ratios to shoulder pain. The subjects were 28 Division I collegiate swimmers and four club swimmers. Shoulder flexibility measurements were obtained bilaterally using a universal goniometer. Strength and endurance ratios were obtained bilaterally using the Cybex II^® isokinetic dynamometer and the Upper Body Exercise Table^®. The swimmers completed a questionnaire that included a shoulder pain performance scale. The Pearson product moment correlation coefficient and multiple regression (R) analysis were the applied statistics. The results demonstrated that no significant correlation (p > 0.001) existed between shoulder flexibility, strength ratios, and shoulder pain. There was a significant (p ≤ 0.001) negative Pearson's correlation between endurance ratios of external rotation, abduction, and shoulder pain in competitive swimmers. A multiple R of 0.78 was obtained for the combination of external rotation and abduction endurance ratios to shoulder pain, which was significant (p ≤ 0.001). Clinical implications suggest that when evaluating swimmers, clinicians need to be aware of the importance of assessing the endurance ratios of the shoulder abductors and the external rotators at faster speeds. With decreased endurance ratios, competitive swimmers may be more likely to develop shoulder pain.

J Orthop Sports Phys Ther 1992;16(6):262-268.

Key Words: swimmer, muscle strength, flexibility

Strength training of neck muscles, a potentially important approach to injury prevention and rehabilitation, has been limited by the lack of a convenient means of instituting progressive resistance exercise (PRE) programs. By positioning a compressible ball coupled with an air pressure gauge between the head and a wall, eight men, ranging in age from 21 to 46 years, initially measured the maximum voluntary pressure (MVP) generated within the ball (a measure of neck muscle force), while maximally flexing, extending, and laterally flexing their head into the ball. In accordance with PRE principles, they then performed three sets of 10 repetitions of each motion while maintaining ball pressure at 60-80% of the measured MVP. This training program, consisting of three to five sessions per week for 4-7 weeks: 1) increased the MVPs for flexion [to 156 ± 9% (SE) pretraining, p < 0.05], extension [to 162 ± 11% (SE) pretraining, p < 0.05], and lateral flexion [to 173 ± 12% (SE) pretraining, p < 0.05]; and 2) decreased the disparity between the MVPs for left and right lateral flexion, indicating that the weaker side showed greater improvement than the stronger side (p < 0.05). These findings demonstrate that progressive resistance neck exercises, facilitated by a compressible ball coupled with an air pressure gauge, can markedly increase neck muscle strength and decrease lateral force imbalance.

J Orthop Sports Phys Ther 1992;16(6):275-280.

Key Words: cervical muscles, muscle strength, resistive exercise

Past research has reported a high level of correlation between peak torque (PT) and work and between PT and power in the muscles surrounding normal and selected pathological knees. No research to date has examined whether such similarities exist in clients with pathology to the medial compartment of the knee. The purpose of this study was to investigate the relationship between the isokinetic parameters of PT, work, and power for the flexor and extensor muscle groups of patients with grade I medial compartment knee sprains. Isokinetic data were collected from 77 patients (41 males, 36 females; mean age 24.6 yrs) on a Merac dynamometer at the speeds of 60, 180, 300, and 420°/set. The ranges of Pearson correlations between PT and work and between PT and power were 0.75-0.96 for the involved knee flexors, 0.67-0.99 for the involved knee extensors, 0.76-0.98 for the uninvolved knee flexors, and 0.85-0.97 for the uninvolved knee extensor muscles. These findings suggest that PT is representative of work and power and may be the only necessary parameter for isokinetic muscle performance testing of the flexor and extensor muscles of the knee in clients with grade I medial compartment sprain.

J Orthop Sports Phys Ther 1992;16(6):288-292.

Key Words: peak torque, work/power, knee sprain

Index by subject of all manuscripts published by the Journal from July through December 1992.