Most runners have long believed that stretching can improve running, yet few of us actually do it. The good news is that studies prove that stretching does NOT improve endurance running! Furthermore, static stretching before a run can actually impair your performance. Obviously stretching can have therapeutic value, such as when mobility/range of motion is limited, but stretching just to lengthen muscles won’t make you a better runner.
The study cited below is a unique examination of results from 63 studies deemed relevant to endurance runners.
Claire Baxter, Lars R. Mc Naughton, Andy Sparks, Lynda Norton & David Bently (2015) Impact of stretching on the performance and injury risk of long-distance runners, Research in Sports Medicine >International Journal, Volume 25, 2017 - Issue 1, Page(s) 78-90. Link here, https://doi.org/10.1080/15438627.2016.1258640
Basically there are two types of stretches: 1). Dynamic, and 2). Static
1). A dynamic stretch is where you carefully move a joint through its range of motion without stopping. It can be as simple as reaching your arms up with a yawn, to more run-specific moves like lunges, leg swings or butt kicks. The idea is to move through the full range without tension, which warms the muscles and synovia (joint lubricant and cushioning fluid). This is basically just a deliberate and controlled warm-up, not a real stretching regimen.
2). A static stretch is where you hold a muscle in a stretched position for a longer period, typically 30-60 seconds. A muscle will adapt by lengthening, or growing longer, over several weeks or more of repeated stress. While a longer muscle means greater range of motion, most runners simply don’t need it, as compared to gymnasts or martial artists, for example. An acute static stretch before a run will not help your performance or reduce your risk of injury, and chronic stretching outside of your running periods, although it won’t hurt, it doesn’t help either. Basically, static stretching for runners is not a good use of training time.
So I should never stretch?
DYNAMIC stretching before a run is okay. We all know we need to ease into a run so beginning with a dynamic stretch routine is perfect for increasing your range of motion and warming your muscles and synovial fluid. Then ease into your run the first few minutes. Also, holding a stretch for a few seconds (lightly) would be considered a dynamic stretch. Finally, a light static stretch after a run, while it feels great and is also okay, it has no measurable benefit.
Here’s a link to my 60 second Instagram post on how to do a safe ‘dynamic stretch’ warm-up. Enjoy - - https://www.instagram.com/p/BpKZegQlU0b/
DYNAMIC stretching before a run is okay as a warm-up
STATIC stretching is not beneficial to endurance runners performance
Exceptions; A static stretching regimen is often prescribed when needed to improve range of motion/joint mobility
“If it feels good, do it. But stretching just for the sake of stretching won’t make you a better runner.” - Coach Jim