The practice of preparing the body for a run has long included the simple act of stretching, with runners routinely performing held poses to “loosen up” their muscles. Modern sports science has significantly refined this approach, suggesting that how and when one stretches directly influences performance and injury risk. This new understanding has shifted the focus away from traditional methods and toward more active forms of preparation. The question is now which type of stretching is appropriate and when it should be performed in relation to a run.
Static Stretching and Performance
The method of holding a stretch in an elongated position for a sustained period, usually 15 to 60 seconds, is known as static stretching. While this feels intuitive, performing it before running is not recommended for activities involving cyclical movements. Scientific studies indicate that this passive lengthening temporarily decreases muscle power and force production.
This reduction in force is called transient strength reduction, an acute loss of the muscle’s ability to generate maximum tension. For a runner, this effect is counterproductive because it reduces the muscle’s natural stiffness, which is necessary for efficient running. The body relies on this stiffness to act like a spring, recycling energy with each stride. Static stretching can dull this effect and may also impair muscle activation needed for stability during the run.
The Function of a Dynamic Warm-Up
The recommended alternative to holding stretches before a run is the dynamic warm-up, which involves controlled, continuous movements that take the joints through a range of motion. This active preparation is designed to systematically prepare the body for the physiological demands of running. An effective dynamic warm-up raises the core body temperature and increases the heart rate, improving blood flow to the active muscles.
Increased blood flow ensures that oxygen and nutrients are delivered efficiently, priming the muscle fibers for the work ahead. The movements activate the specific muscle groups and neural pathways used during the run. By engaging muscles through controlled contractions, the nervous system learns how to regulate movement in the joints, enhancing coordination and mobility. This type of warm-up has been shown to improve running economy, a measure of how efficiently a runner uses oxygen.
Runners should incorporate exercises that mimic the running motion, starting slowly and gradually increasing the range and speed of movement. A concise dynamic routine, performed for about 5 to 10 minutes, ensures the body is physically and neurologically ready to perform. Practical examples include:
- Walking lunges, which prepare the hip flexors and quadriceps.
- Leg swings, which improve hip mobility.
- High knees, which actively engage the hamstrings and glutes.
- Butt kicks, which prepare the calves and hamstrings.
The Place for Flexibility Work
While static stretching is discouraged as a pre-run warm-up, it holds a proper place in a runner’s routine for long-term flexibility goals. The primary function of this stretching is to maintain or increase the resting length of muscle tissue over time. This goal is best pursued when the muscles are already warm and more pliable, making them more responsive to lengthening.
The appropriate time to perform static stretching is during the cool-down phase immediately following a run, or as a separate session entirely. After exercise, the elevated muscle temperature allows for a safer and more effective increase in range of motion. Holding stretches post-run can also aid in muscle relaxation and help reduce muscle tension built up during the activity.