Similar to what you should eat before and after a run, or what type of recovery strategies can improve performance, stretching can fall into a grey area — the kind filled with contradictory advice and plenty of opinions.

Is stretching optional or mandatory for runners, for example? Can it really offer up injury prevention? Is stretching ever a bad idea?

Here’s a look at common misconceptions, along with research- and expert-backed facts so you can use stretching to your performance advantage.

Myth 1: The Type of Stretching You Do Before a Run Doesn’t Matter
All forms of flexibility training are good, right? If that were true, then it wouldn’t matter whether you did static stretching (in which you hold a stretch for about 30 seconds or longer) before a run or did dynamic stretching — which involves movement during a stretch, such as walking lunges, squats, or even some easy yoga flows.

Although both of these types of stretching play a role in improving your range of motion, it’s generally a good idea to save static stretches for after a workout when your muscles are warm. So make that kind of stretching part of a cool-down, Meg Takacs, a certified running coach tells Runner’s World.

“Focusing on dynamic movement pre-running is helpful for activating the muscles you’re just about to use, and it can also improve your range of motion, which often leads to better running mechanics,” Takacs explains. Dynamic stretching is also a boon before any cross-training you do, whether that’s Pilates or strength training, she adds.

It doesn’t take much commitment to see benefits, either. A study in the Journal of Strength and Conditioning Research that looked at the effects of dynamic stretching before a high-intensity run found that one set of 10 reps of moves that targeted five muscle groups — hip extensors and flexors, leg extensors and flexors, and plantar flexors — significantly improved endurance running performance. Those performance improvements were measured by time to exhaustion and total running distance.

Static stretches, on the other hand, can have the opposite effect. In a study in the Journal of Physiology, researchers compared the outcome of static stretching versus dynamic stretching for runners, and specifically for activities like sprinting. They found that doing only static holds for over a minute was associated with substantial declines in strength and power performance. The researchers added that some short-duration static stretching of up to 60 seconds isn’t as harmful — but it should “be applied with caution due to its negligible but still prevalent negative effects.”

Myth 2: Static Stretching Does Nothing
While opting for dynamic stretching before a run is the best approach, that doesn’t mean you should ditch the static stretches completely. Slowing to a walk after your run may seem like enough of a cool-down, but throwing a few stretches into the mix can get you back to your normal resting state faster and may help increase flexibility overall, according to Aaron Leventhal, owner of Fit Studio and author of The New Fit.

“In terms of static stretching after a run, holding each stretch — such as standing hamstring stretch or seated butterfly — for about 20 to 30 seconds can help because it sends a signal to the nervous system to reset back to your baseline,” he tells Runner’s World.

That’s important because exercise creates a notable increase in stress on the body. While that’s beneficial in the short term, it’s also crucial to get the nervous system back to its usual rate of respiration, cardiac output, and metabolic processes as soon as possible to limit that stress, according to the National Center for Biotechnology Information. An extended cool-down, with those static stretches, can help.

“With the athletes I coach, whether they’re in high school or they’re masters athletes, static stretches are an opportunity to get their heart rate down, which is especially important if you’ve done an intense or longer-duration run,” USA Triathlon-certified coach, Kristen Hislop tells Runner’s World.

Static stretching may also aid with improving your range of motion. In fact, research suggests it can help with hip flexion in particular, according to a research review in the Journal of Sport and Rehabilitation. That research found that static stretching after exercise may also help with hamstring extensibility — which is the ability of your hamstrings to stretch past their resting length, which is a key component of preventing injuries like muscle strain.

Myth 3: You Can’t Stretch Too Much
Too much of anything can become problematic, and stretching is no exception, says Eon Jarvis,a physiotherapist at the University of Utah's Orthopaedic Center.

“When you stretch too often or for too long, it may lead to muscle irritation,” he tells Runner’s World. “This can worsen if stretching seems to provide short-term relief from pain, such as muscle soreness, because that might make it seem like stretching is a remedy. However, if the pain returns or doesn’t improve over time, you should likely focus on strengthening those muscles instead of stretching them.”

Frequent, intense, and long-duration stretching may also reduce running economy, according to a study in Research in Sports Medicine. That’s because it can reduce musculotendinous stiffness — which is a measure of the amount muscles and tendons resist being stretched. An overabundance of this stiffness may contribute to injuries and poor movement patterns. On the other hand, too little of it may affect running mechanics, Leventhal says. That’s because stiffer tendons and muscles act like springs, propelling a runner forward with greater power and reloading quickly to generate force for the next stride.

This sets up a Goldilocks problem: How do you figure out how much stretching is the “just right” amount that can improve flexibility without losing musculotendinous stiffness?

“As with many strategies when it comes to running, the answer will come down to how you respond on an individual level, and it can take some trial and error to figure it out,” says Takacs.

In terms of general guidelines, tune into where you feel areas of tightness to figure out if you need to stretch or strengthen that area.

Another tip: Logging how you stretch - including specific movements, for how long, and how often you do them - can be a good first step toward understanding how stretching is affecting you and your running performance overall.

https://www.runnersworld.co.za/training/what-active-stretching-actually-means-and-how-to-incorporate-it-into-your-mobility-training/

Myth 4: You Only Need to Stretch on Run Days
Using dynamic stretching before a run and static stretching afterward has been shown to be beneficial, but does that mean you don’t need to stretch on your rest days? Taking that approach might hinder your efforts to increase overall mobility, believes Hislop.

Research backs this up: A systematic review and meta-analysis published in 2024 in Sports Medicine says that acute static stretching (defined as about four minutes per session) has a moderate positive effect on flexibility, while chronic static stretching (10 minutes per week) has a large positive effect on flexibility.

Let’s take the hip flexors for example. If you perform the Thomas Test and find out you really do need to work on flexibility of the hip flexors, it’s not the best approach to just stretch once and you’re done. Like running, you need consistency. In order to actually see improvements in range of motion, set a goal to stretch your hip flexors for about two minutes five days a week or four minutes three times a week.

“I think everyone should start their day with some mobility work,” Hislop says. “Pick three moves in the morning and be consistent. Currently, mine are sitting at the bottom of a squat, 90/90 hip rotation, and thoracic spine rotation. We need our bodies to move well in general in order to run well.”

For certified running coach Amanda Grimm from We Run, adding 15 to 20 minutes of yoga on rest days makes a big difference for overall flexibility and range of motion for herself and her clients, she tells Runner’s World. She also targets areas on her body that are prone to tightness on days she doesn't run, which she says tends to help her running form.

“Not confining your stretches to run days and putting them in your regular routine instead will enhance overall mobility and help maintain muscle health,” she adds.

Another bonus for daily mobility work through strategic stretches: You’re likely to identify imbalances more easily. For example, you may realise you have differences in range of motion from left to right.

“This can help you identify what is holding you back from doing your best,” says Hislop. “That will help guide how much you need to do before, after, and between runs.”

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