Stretching is good for us, right? Well, yes and no! It turns out that you have to do the right kind of stretching for the right duration at the right time according to what activity you are about to do. This article makes sense of the confusing mass of literature about stretching and will allow you to give individually tailored, sport-specific advice to your clients about how to get the benefits of stretching while avoiding the potential decrease in power output. This is not only crucial for the professional athlete where marginal gains can make all the difference, but is also useful for amateurs looking for improvements too.
A commonly held belief, by both professionals and the public, is that a static stretching (StS) plays an important role in injury prevention and improving athletic performance. It is common practice therefore for athletes of all levels, both recreational and professional, to include StS in their routine. This may be during a ‘warm up’ before a game or run, at the end of a run or activity, or as part of a strength and training or rehabilitation programme.
Historically, until the 1990s, it was believed that StS promoted flexibility and improved athletic performance. This was mainly based on the thought that greater range of motion (ROM) reduced resistance to movement and improved movement economy.
Since the early 2000s, research had started discussing the potential harmful effects of StS on strength and power-related activities. Acute ROM improvements can be countered by decreases in muscle performance, primarily after prolonged StS. As a result, it has been widely recommended to avoid performing prolonged StS before strength and power related tasks, with dynamic stretching exercises being favoured instead. Dynamic stretching techniques typically induce either an increase or no change in muscular force and power.
Subsequent to this,new evidence challenged the view that StS was taboo and should not be conducted before activity or performance. Findings by Behm et al. and Kay et al. showed that short duration acute StS ( <60s) had trivial negative effects on strength and power as opposed to prolonged static stretching(StS) >60s. In addition to this, recent findings demonstrated that when short duration StS was included in a full warm up routine, it did not impair subsequent strength and power performances. For clarity, the stretch times discussed in research are total time per muscle group, so a total of less than 60s of stretching does not seem to be detrimental, but greater than 60s does. Thus, 3 x 30-second stretches of the quadriceps equates to 90s,potentially inducing deficits in muscle strength and power according to the research.
“Since the early 2000s, research has started discussing the potential harmful effects of static stretching on strength and power-related activities”
“Static stretching in a warm-up can be useful for sports where pronounced joint ROM is required”
“For runners, static stretching can help reduce acute muscle injuries and if it is used for short durations and is combined with active warm-up activities, there are no detrimental effects on performance”
“It is now generally agreed that short-duration stretching exercises could be performed within a comprehensive warm-up procedure and that slow conducted dynamic stretching is also recommended”