Pre-exercise Stretching and Performance

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Pre-exercise Stretching and Performance
Research offers insight into flexibility, function
and the pros and cons of stretching prior to activity.
Janot, Jeffrey M., Lance C. Dalleck, and Corey Reyment.


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This journal review was published on September 17, 2008 in our Private Members Area. For more articles like this one, and a heap more flexibility tools and resources, check out the new Private Members Area here.

a) Outline of the Study
This study provides an extensive review of literature relating to pre-exercise stretching and its effect on athletic performance. In addition to acute static stretching, the study considers the effects of proprioceptive neuromuscular facilitation (PNF), ballistic and dynamic stretching. While each of these techniques has shown effectiveness in various studies examining ROM, they appear to differ in their impact on exercise performance.

The article begins with a helpful primer on the physiology of acute stretching, outlining the mechanical and neural factors believed to be involved in post-stretching muscular deficit. The review reiterates the evidence of recent research which suggest that pre-exercise stretching may be of limited utility for injury prevention and further, may unfavorably impact athletic performance.

Finally, a holistic assessment is provided to help athletes determine the timing, duration and form of stretching best suited to achieving particular goals. Dynamic rather than static stretching is favored in general for positive results.

b) What the Study Was Trying to Prove
By focusing on a broad range of studies relating to post-stretching performance, the study seeks to clarify current understanding of stretching benefits and downsides. While certain performance benefits previously ascribed to stretching have not been born out in the material this study reviews, nevertheless, goal-directed stretching for specific purposes and under particular timing conditions may be beneficial. Areas for further research are also considered.

Stretching-induced force deficits have been observed in a number of studies. The present article suggests both mechanical and neural factors which may be responsible. On the mechanical side, temporary loss of muscular stiffness following stretching is believed to cause decreases in force and power production. Neural factors include decreased neuromuscular activation, (though the precise mechanism leading to decreased force and power production remains poorly understood).

Performance deficits from pre-exercise stretching appear in cited studies relating to muscle strength and power, maximal voluntary contraction (MVC) of the plantar flexors, peak torque and mean power output, jumping performance, running speed and economy, and muscular strength endurance.

c) Summary of Results
With respect to acute static stretching, the study summarizes their results as follows: “Collectively, present research findings suggest that there are no ergogenic benefits, and there are potentially detrimental effects, to incorporating static-stretching exercises into the warm-up routine.” That being said, the study does find benefit in dynamic stretching, which involves movements designed to mimic specific actions occurring during athletic performance.

Dynamic stretching for example, yielded significantly faster 10m run times (acceleration) as well as better zigzag run times implying increased agility as compared with both static and no stretching routines. Dynamic stretching also significantly improved speed as seen in flying 20 m run times. Such dynamic stretching protocols are believed to enhance blood flow and increase core temperature.

d) Conclusions
The authors conclude their review by stressing goal-directed stretching based on current data. These suggest that athletes requiring enhanced ROM (such as dancers, divers, gymnasts or those in post-rehabilitation) will benefit from stretching, though others requiring increased explosive power, strength or jumping ability may see their output diminished by pre-exercise stretching. While results on dynamic stretching are preliminary, the technique seems promising in terms of delivering benefits and reducing or eliminating muscular reduction typical of acute static stretching regimens.

Stretching is one of the most under-utilized techniques for improving athletic performance and getting rid of those annoying sports injuries. Don't make the mistake of thinking that something as simple as stretching won't be effective.