By Carolyn Crist

(Reuters Health) – It’s a common and persistent myth that static stretching improves running performance and decreases the risk of injuries, researchers say.

Instead, an active warm-up can help with running performance, and progressive training can reduce injury risk, they write in the British Journal of Sports Medicine. There’s evidence stretching can help keep joints flexible and that it won’t harm performance, but it won’t help either, they write.

“Runners have certain beliefs around running injury risks, injury prevention and performance that are in contrast to current research evidence,” James Alexander of La Trobe University in Melbourne, Australia, told Reuters Health by email.

“These beliefs drive runners to continue to pursue ineffective or non-optimal strategies within their running training, whether through static stretching for injury prevention or low-load strength training for performance,” said Alexander, lead author of an infographic designed to distinguish evidence from myth.

Alexander and his co-authors are physiotherapists and researchers who run most days of the week and work with different types of runners with different abilities and strengths. While talking with these runners, he said, they often discuss myths and misunderstandings around running injuries and explain recommendations around stretching and warm-up activities.

To inform other runners, they created a series of five “Running Myth” infographics that will be published in the journal in upcoming months. They previously discussed strength training and heavy resistance exercises.

In this infographic, they bust the belief that static muscle stretching, or lengthening a muscle to the point of tension for 30 seconds per stretch, reduces injuries. Some runners use static stretching to reduce delayed-onset muscle soreness after strenuous runs, but research doesn’t support this idea either.

Stretching can improve joint range of motion and help runners relax after a run, the authors note.

Since running places stress on the joints and soft tissues, runners face a high risk of developing running-related overuse injuries such as joint pain, shin splints, IT band syndrome and Achilles tendinitis. These problems often occur when runners increase running frequency, intensity and duration too quickly.

To help the body adapt and strengthen, runners should build their running performance through progressive training sessions, which should incorporate an active warm-up that involves 5-10 minutes of walking or light jogging. If preparing for a fast race or training session, this could include 6-8 dynamic stretching drills to move the joints through the full range of motion, particularly in the lower limbs, such as walking lunges and leg swings. In addition, the authors recommend ending the warm-up with three short running bursts at the goal running pace, such as three 100-meter dashes.

Importantly, the authors note, research shows that warm-ups improve running performance, but the evidence is still unclear about whether they reduce injuries. Progressive training and the improved running performance itself will reduce the injuries, they add.

“Many runners stretch because, as a result of high-volume repetitive movements, joints and muscles start to feel stiff and tight,” said Richard Blagrove of Loughborough University in the UK, who wasn’t involved with the infographic.

Static stretches reduce the stiff and tight sensations in the short-term because they extend the nerves in the overworked tissues, but that doesn’t reduce injury risk in the long-term, he added.

“If runners wish to do a small amount of static stretching and find anecdotally that it helps them, it probably won’t negatively impact performance or increase injury risk,” he told Reuters Health by email. “Rather than prioritizing static stretching, runners would be better off engaging with specific strength training exercises and progressing their running at a sensible rate to avoid injury.”

SOURCE: British Journal of Sports Medicine, online November 6, 2019.