Dynamic stretching is the best type of stretching before a workout. Unlike static stretching, where you hold a position for 30 seconds or more, dynamic stretching uses controlled, repetitive movements that take your joints through their full range of motion. This approach warms up your muscles, primes your nervous system, and either maintains or improves your power output for the activity ahead.
Why Dynamic Stretching Works
Dynamic stretching involves active movements like leg swings, walking lunges, and arm circles. Each repetition contracts and relaxes the muscle, which generates heat through a pumping action and increases blood flow. As muscle temperature rises, the tissue becomes less stiff and more extensible, and nerve signals travel faster. The result is smoother, more efficient contractions right when you need them.
These effects show up in measurable ways. Research on range of motion found that a single session of dynamic stretching increased flexibility by 7% to 10% immediately afterward, and that improvement held for up to 90 minutes. Passive muscle stiffness dropped by as much as 16.7% and stayed reduced over the same window. That means you have a generous buffer of time between your warmup and the start of your workout without losing the benefits.
Pain tolerance also shifts briefly in your favor. The force needed to trigger discomfort in a stretched muscle increased by about 10% right after dynamic stretching, though this effect faded back to baseline within 30 minutes. So the window for the most comfortable, high-output movement is roughly the first 15 to 30 minutes post-warmup.
The Problem With Static Stretching Before Exercise
Static stretching, the kind where you hold a hamstring stretch or quad pull for an extended period, isn’t harmful in every case. The critical variable is how long you hold each stretch. In a study comparing 30-second and 60-second static holds on the hamstrings, a 30-second hold produced no significant loss in force production compared to no stretching at all. But a 60-second hold dropped maximum voluntary force from about 288 newtons down to 262, roughly a 9% decline.
That matters if your workout involves sprinting, jumping, heavy lifts, or anything that demands explosive power. When researchers compared peak power output after dynamic versus static warmups, dynamic stretching consistently trended higher, with one study showing a small-to-moderate performance advantage. The differences weren’t always dramatic, but they consistently favored dynamic stretching for activities requiring speed and force.
The takeaway isn’t that static stretching is dangerous. It’s that long-hold static stretches temporarily reduce your muscles’ ability to produce force, and doing them right before explosive activity puts you at a slight disadvantage. Save them for after your workout, when improving flexibility without needing peak power is the goal.
Does Pre-Workout Stretching Prevent Injuries?
The evidence on stretching and injury prevention is less clear-cut than most people assume. Very few studies have isolated dynamic stretching on its own to see if it reduces injury rates. One study of 465 high school soccer players found no significant difference in injury counts between a group doing only dynamic stretching and a group combining dynamic with static stretching.
What does show consistent benefit is a complete warmup that pairs dynamic stretching with dynamic activity, things like light jogging, agility drills, or sport-specific movements. Across 17 studies reviewed in a 2023 analysis, warmups built around this combination reduced injury incidence. A separate study on competitive ballroom dancers found that an eight-week program of dance-specific dynamic stretching significantly improved ankle joint stability in athletes with a history of ankle injuries.
So dynamic stretching alone isn’t a guaranteed shield against injury, but it’s a core ingredient of warmup routines that do reduce risk. The key is combining it with some form of light aerobic activity that raises your heart rate and body temperature before you push hard.
How to Build a Dynamic Warmup
A good dynamic warmup takes about 5 to 10 minutes and targets the major muscle groups you’ll use during your workout. Move through each exercise in a controlled way, gradually increasing the range of motion with each rep. You’re not bouncing or forcing anything. You’re easing your body into bigger, faster movements.
Lower Body Movements
- Walking lunges: 2 to 3 sets of 10 to 15 reps per side. Step forward into a deep lunge, keeping your front knee over your ankle, then push off into the next step.
- Hip circles: Stand on one leg (hold a wall if needed) and swing the opposite leg in circles out to the side. Do 20 circles in each direction, then switch. Start small and widen the circles as you loosen up.
- Walking knee hugs: Pull one knee to your chest as you walk forward, alternating sides. Try 1 to 2 sets of 20 total reps.
- Walking butt kicks: As you walk or jog forward, kick each heel up toward your glutes. Do 10 to 20 kicks per side.
- Walking high kicks: Swing one leg straight up in front of you while reaching toward your toes with the opposite hand. Do 30-second sets.
Upper Body and Full Body Movements
- Arm circles: Extend your arms out to the sides and make circles, 30 seconds in one direction and 30 seconds in the other. Repeat 2 to 3 times.
- Arm swings: Swing both arms across your chest and back out to the sides. Do 10 to 15 reps per side.
- Inchworms: From standing, bend forward and walk your hands out to a plank position, then walk them back. Do 2 to 3 sets of 10 to 15 reps. These warm up your hamstrings, shoulders, and core simultaneously.
- Lunges with a twist: Step into a forward lunge, then rotate your torso over the front leg. This opens up the hip flexors and mid-back at the same time.
Matching Your Warmup to Your Workout
The most effective warmups mirror the movements you’re about to do. If you’re preparing for a run, emphasize leg swings, high kicks, and butt kicks. For an upper body lifting session, prioritize arm circles, arm swings, and inchworms. A full-body session calls for a mix of everything.
Start with 3 to 5 minutes of light aerobic activity, like brisk walking or easy jogging, to raise your core temperature. Then move into your dynamic stretches. This combination of general cardiovascular warmup plus movement-specific dynamic stretching is the format that research most consistently links to better performance and fewer injuries. By the time you pick up a barbell or start your first sprint, your muscles should feel warm, loose, and ready to produce force.