The Do's and Don'ts of Stretching

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The Do's and Don'ts of Stretching

Despite limited evidence, stretching has been advocated for years as a key element of fitness programs to decrease injury risk, relieve pain associated with stiffness, and improve overall athletic performance.

The proposed benefits of stretching include a direct decrease in muscle stiffness via passive viscoelastic changes and an indirect decrease as the result of reflex inhibition and consequent viscoelasticity changes from decreased actin-myosin cross-bridging.
Common misconceptions and misinterpretations about stretching among patients and health care practitioners prompted this literature review on stretching and range of motion. Included in the discussion are topics such as: short and long-term effects of stretching; ideal duration and frequency of stretching; passive vs. active warmup; and rationale for individualized programs.
Based on the published evidence, the authors offer the following "take-home points" as a summary of their findings:

Heat, ice and warm-up all increase the effectiveness of stretching. However, only warm-up is likely to prevent injury.
One 30-second stretch per muscle group is sufficient to increase range of motion in most healthy people. Longer periods or more repetitions may be needed for some people.
Proprioceptive Neurological Facilitation (PNF) stretching appears to be the most effective technique for increasing range of motion. Specifically, the agonist-contract-relax method is more effective in increasing range of motion than the contract-relax method. However, the mechanism behind this stretch is an eccentric muscular contraction which may increase the risk of injury compared with static stretches.
Individuals may be able to determine appropriate stretching duration and style by holding a stretch until no additional benefit is obtained.

Conclusion: Clinicians should familiarize themselves with the demands of different stretching techniques on muscles when making recommendations to patients. An individualized approach may be most effective, based on intersubject variation and differences between healthy and injured tissues.
Shrier I, Gossal K. Myths and truths of stretching: individualized recommendations for healthy muscles. The Physician and Sportsmedicine, Aug. 2000:28(8), pp1-10.