If something you did could improve performance, decrease risk of injury, and help you feel better on a run, all in less than five minutes’ time, you would do it consistently. While not a magic bullet, dynamic stretching can achieve all those things.
Unlike static stretching (more on the science here), both theoretical and practical evidence points to the positive impact of dynamic stretching on performance. Dynamic stretching improves joint range of motion without sacrificing muscle tension.
There are two types of dynamic stretching: active and ballistic. Active dynamic stretching moves through the range of motion several times. Ballistic stretching involves rapid “bouncing” at the end of range of motion and is generally no longer recommended. For the sake of this article, dynamic stretching will refer to active dynamic stretching.
What the Research Says About Dynamic Stretching
The scientific literature does not reach a completely clear consensus on dynamic stretching. A 2015 and 2019 study performed by the same group of researchers (Yamaguchi, Takizawa, Shibata, et al) reached two different conclusions about the role of dynamic stretching in a warm-up. In part, this may be due to inconsistent dynamic stretching protocols used throughout studies. Is it leg swings, lunges, or A-skips? Does the timing of the dynamic warm-up make a difference? What confounding variables are present?
That considered, let’s delve into what some of the research says. A 2015 study in the Journal of Strength and Conditioning found that, while no effects were seen on running economy or oxygen uptake (VO2), velocity at 90% of VO2max improved in response to dynamic stretching. Those who performed dynamic stretching (1 set of 10 reps for 5 lower body muscle groups) saw improvements in both time to exhaustion and total running distance. 90% of VO2max is approximately a 3K to 5K race – meaning that dynamic stretching would improve performance at these distances. Most likely, since the improvements were related to endurance rather than oxygen uptake, the results could be extrapolated to longer distances.
A 2017 study in the Journal of Strength and Conditioning Research concluded that dynamic stretching results in a small increase in lower limb force production during treadmill running. For many runners, increase force production equates to faster running.
However, a 2012 study in the same journal saw no difference between 15 minutes of dynamic stretching and 15 minutes of quiet sitting on a 30-minute time trial for well-trained male runners. Interestingly, the runners who performed dynamic stretching had a higher energy cost on the run. However, that could be due to confounding variables.
When Should You Do Dynamic Stretching?
Timing does matter for dynamic stretches. A 2019 study in Research Quarterly for Exercise and Sport observed that a dynamic stretching routine (same one from the above 2015 study) led to a shorter time to exhaustion at 90% VO2max when performed after a warm-up run. Now, that’s just one study – not Gospel truth – and there could have been numerous confounding variables. It does suggest the idea that runners should complete dynamic stretching before any running at all. Independent of this study, many coaches suggest dynamic stretching prior to any running. (This differs from strides and drills, which are best done after a warm-up jog.)
What are the Benefits of Dynamic Stretching?
In terms of performance, dynamic stretching has zero to positive effect on performance. Most likely, this depends on the runner; we all know those genetic outliers who never warm-up, never foam roll, and run all their easy runs too fast, yet outperform those who train optimally. Unlike static stretching, dynamic stretching will not impair your performance.
The benefits of dynamic stretching go beyond performance metrics. Dynamic stretching prepares the body for movement – which is essential for runners, especially early in the morning or after work. Dynamic stretching improves the range of motion of your joints and begins to elevate both heart rate and core temperature. This ensures that you are not going into your run cold.
Jay Dicharry, a physical therapist and biomechanics researcher, emphasizes the nervous system benefits of dynamic stretching. In his book Running Rewired, he remarks, “Some light movements, such as leg swings, hops, and other stuff…effectively prepares your nervous system to move smoother….[Dynamic stretching] resets the muscle to allow you to move smoothly.”
The most significant benefit of dynamic stretching is an improvement in mobility before a run. The end goal of dynamic stretching is mobility. For runners, mobility equates to a more economical stride and a lower risk of injury. Lack of mobility in the hips may hinder glute activation and proper running form. Full mobility in the hips facilitates a smooth, efficient stride.
What Should My Dynamic Warm-Up Include?
A dynamic stretching routine should be specific to the sport. A swimmer, weight lifter, and runner will perform slightly different dynamic stretches according to the demands of their sport. For a runner, that includes movement in the sagittal plane, with some frontal plane (for stability). These movements will focus on warming up the hips and glutes.
Dynamic stretching does not have to be a complex, prolonged routine. Pick a few dynamic stretches and do them consistently before each run. Based on how your body feels, customize the routine. You can try these dynamic stretches (click link for video demonstrations). Alternatively, a simple routine of 10 leg swings, 10 lateral band walks, and 10 monster band walks is effective and quick.