Background and purpose: Stretching (that is, interventions that apply tension to soft tissues) induces increases in the extensibility of soft tissues, and is therefore widely administered to increase joint mobility and reverse contractures. However, it is not clear whether the effects of stretching are lasting. A systematic review was conducted to determine if stretching (either self-administered, administered manually by therapists or by some external device such as a splint) produces lasting increases in the mobility of joints not directly affected by surgery, trauma or disease processes.
Method: In order to determine the lasting effects of stretching, only studies that measured joint range of motion (ROM) at least one day after the cessation of stretching were included. MEDLINE (from 1966 to June 2000), EMBASE (from 1988 to June 2000), the Cochrane Controlled Trials Register and PEDro databases were searched, and citation tracking was used to identify randomized studies that met the inclusion criteria. Each study was rated by two independent assessors on the PEDro scale, which rated trials according to criteria such as concealed allocation, blinding and intention-to-treat analysis.
Results: Thirteen studies satisfied the inclusion criteria. All examined the effect of stretching (median number of stretch sessions = eight) on joint ROM in healthy subjects without functionally significant contractures. Four studies were of 'moderate' quality and the remaining nine were of 'poor' quality. The 'moderate' quality studies suggest that regular stretching increases joint ROM (mean increase in ROM = 8 degrees; 95% CI 6 degrees to 9 degrees) for more than one day after cessation of stretching and possibly that the effects of stretching are greater in muscle groups with limited extensibility.
Conclusions: The results of four 'moderate' quality studies show a convincing effect of stretching in people without functionally significant contracture. These findings require verification with high-quality studies. Lasting effects of intensive stretching programmes (for example, stretching applied for more than six weeks or for more than 20 minutes a day) or of stretching on people with functionally significant contracture have not yet been investigated with randomized studies.