In the past, athletes didn't always to do dynamic warm up exercises. Back in 'ye olden days' of sports science, the 1980s, some pretty smart exercise science professors had the idea to stretch prior to exercise. The idea was simple: increasing joint mobility and range of motion would decrease the likelihood of injury. One great example of this comes from running, where groin injuries are rampant due to the stride of runner. Stretching before a run can give the extra range of motion to prevent pulling or tearing the muscle during exercise. And the idea of improving mobility prior to exercise is a sound one, but eventually exercise scientists started to notice a new phenomenon.
As noted in a paper by McHugh and Cosgrave, muscle strength and power decrease following even a single bout of static stretching. For a 100m runner, a soccer player, or a tennis player, these were unacceptable sacrifices and the result was an interesting dynamic. If athletes stretched, they had less muscle strength, but if they didn't stretch, they had an increased risk of muscle strains. To the rescue came: dynamic stretching.
Dynamic Stretching Basics
Dynamic stretching appears to be the right balance between improving flexibility while simultaneously maintaining muscle strength and power. Let's look at the basics principles of dynamic stretching:
Firstly, dynamic stretching is a smooth, consistent, and controlled movement through a joint range of motion. The goal here is to guide the body through its full range of motion to induce a response in the muscles where in the future they are more easily able to reach that same position. These stretches should be done after a conservative 5 minute general warm up. The classic analogy compares our muscles without a warm up to taking a rubber band out of the freezer. The rubber band is more likely to snap or rip right away than if we warm it up in our hands for a few minutes before trying to pull on it.
The warm up could consist of any kind of active movements that bring the blood to our extremities without any dramatic movement patterns. Some examples include a brisk walk, a light jog, or a short bike ride around the block.
Dynamic Warm Up Routine/Protocol of Exercises
The following exercises are an example protocol from a recent study on dynamic warm ups. We will discuss the study in more detail below, but it appears that moving through each of these patterns for each leg 3-4 times is sufficient to see improvements in flexibility. These stretches are illustrated by OpenSim models. Remember: smooth, consistent, controlled are the key characteristics to proper dynamic stretching.
Walking Knee Hugs / Walking Knee Raise / Knee to Chest
Walking Quad Stretch / Walking Butt Kick
Walking Leg Cradle / Standing Leg Cradle
Hip Open Circles / Hip Openers
Hip Closed Circles / Hip Closers
Straight Leg March / Toy Soldiers / Frankensteins
Forward Lunge / Upright Lunge
Forward Lunge with Arm to Ground / Runner's Lunge
Side Lunge / Groin Stretch
Skips with High Knee
Considerations for a Dynamic Warm Up
As I mentioned previously, this protocol was used in a studywhich focused on determining the optimal amount of time to spend on dynamic warm up exercises. The purpose of that study was to compare a few key characteristics between athletes who did not stretch, athletes who completed a 6 minute dynamic stretching protocol and athletes who completed a 12 minute dynamic stretching protocol. Essentially, the 6 minute group completed 3-4 repetitions of each of these movement patterns and the 12 minute group completed 7-8 repetitions of each of these movements. The control group completed the 5 minute general warm up then rested 12 minutes to keep the total time the same.
The study then compared vertical jump height, flexibility, and muscular endurance for each group. The big takeaways from the study are as follows:
The results of this study give significant insight into the optimal protocol for dynamic stretching. It appears a 6 minute protocol may be optimal for finding a good balance between flexibility and muscle endurance. It appears that as time spent dynamic stretching increases, vertical jump, flexibility, and muscular endurance characteristics improve for a period and then start to worsen at longer intervals.
The best part about this study is that it concludes that 3-4 repetitions of these 12 movement patterns is likely the optimal warm up for muscle endurance, power, and flexibility. The total time is only 11 minutes! There is no excuse for any athlete to not complete a dynamic warm up routine given the short time it takes to see dramatic improvements in performance characteristics.
Why do Cyclists Need Flexibility and Dynamic Warm Up Exercises?
Cycling is inherently a constrained sport. When we clip in, sit on the seat, and put our hands on the handlebars, we force our body into a specified position. Our leg position is dictated by the positions of the pedals and our upper body position is dictated by the preset distance between the handlebars and the saddle. It may seem intuitive that since cyclists do not move their joints through their entire range of motion, that flexibility may not be significant.
In reality, many cyclists approach their joint range of motion throughout the pedal stroke. One good example of this is the hamstrings at the bottom of the pedal stroke (6 o'clock). If the hamstrings are sufficiently short, they may become maximally extended while riding. A cyclist may compensate for this by rotating their pelvis backwards in the saddle or by rocking their hips back and forth. Day after day these compensation patterns start to fatigue the lower back and can cause pain and spinal issues.
Even on a single given ride, muscle fatigue can cause a decrease in muscle length and compensatory patterns can develop. One way to avoid these compensatory patterns is to improve flexibility. A routine of dynamic warm up exercises attempts to provide a short term increase in flexibility for a given event to improve performance and decrease instances of compensatory patterns.