Effect of 12-week isokinetic training on muscle strength in adult with healed thermal burn.

Introduction: Severe burns result in marked and prolonged skeletal muscle catabolism and weakness, which persist despite 'standard" rehabilitation programmes of occupational and physical therapy. Therefore, the objectives of this study were of twofold: to quantify the long-term effects of burns on leg muscle strength and to assess whether adults with thermal burn would benefit from the isokinetic training programme.

Materials And Methods: Burned adult patients, with 35-55% total body surface area (TBSA) burned, were assessed at 6 months after burn in respect to leg muscle strength at 150° s(-1), using isokinetic dynamometry. Non-burned adults were assessed similarly, and served as controls. The burned adults participated in the resistance training programme 3 times weekly. The isokinetic exercise programme was begun with 60% of the average peak torque. Intensity of isokinetic exercise was increased from one set to five sets during the first through fifth sessions and remained at six sets for the remaining 6th to 24th sessions. Finally, a dose of 10 sets was applied for the 25th to the 36th sessions. Each set consisted of five repetitions of concentric contraction in angular velocities of 150° s(-1) for knee extensors, and flexors. All exercise sessions were preceded by a 5-min warm-up period on the treadmill.

Results: Subjects with burns more than 35% of TBSA produced significantly less torque, work, and power in the quadriceps and hamstring than control subjects (20.5%, 15.2%, p<0.05). Three months after isokinetic programme, muscle strength further increased by 17.9%±10.1% compared to the baseline measurement for burned patients but continued to be below the concurrent age-matched, non-burned adult.

Conclusion: We found that adults with severe burns, relative to non-burned adults, had significantly lower peak torque as well as total work performance using the extensors and flexors muscles of the thigh. Participation in isokinetic training resulted in a greater improvement in extensor and flexor muscle strength in adults with held thermal burn compared to base line values.