Running Flexibility: Do Runners Need To Be Flexible?
Running and flexibility are hardly synonymous terms, but should they be? Here, the reasons that flexibility is essential for a runner will be discussed. As we always do at Airia Running, we are going delve into the science behind running flexibility to leave you feeling confident and comfortable with the information provided.
What is Flexibility?
For runners, the word “flexibility” is most often used to describe whether someone can touch his or her toes. However, functional flexibility is much more than simple hamstring elasticity. Instead, flexibility describes how much movement is available at a given joint. For instance, runners that are unable to bend over and touch their toes shouldn’t blame their hamstrings, as the problem might be caused by poor range of motion in the hips and pelvis.
There are many factors that affect flexibility. For instance, the construction of the joint is important. A ball and socket joint like the shoulder is naturally going to have a greater range of motion than a hinged joint, such as the elbow. The elasticity of surrounding muscle tissue, tendons, and ligaments also plays a role in flexibility. Muscles should be most flexible while tendons should have less elasticity.
Ligaments should not be lax and cause excessive joint movement, but rather be tight and hold everything into place. Body and environmental temperatures also matter. Warmer body temperatures and weather conditions are best for optimal muscle and joint movement. Finally, injury, age, and gender can all affect a person’s range of motion. For instance, flexibility decreases with age and females tend to be more flexible than males.
Why is Flexibility Important?
To understand why flexibility is important, it is necessary to understand the normal movement of joints. Muscles must work in tandem in order to initiate movement. For each joint, one muscle works as a flexor while another works as the extensor to promote movement.
First, the flexor muscle contracts in order to bend the joint. To return the limb back to the starting position, the extensor muscle then contracts to straighten the joint. For instance, when you bend your elbow the biceps muscle acts as a flexor while the triceps muscle serves as the extensor.
Therefore, flexibility is important because it maintains a sense of balance within the body. Since muscles work in pairs, an inflexible extensor muscle could prevent the joint from returning to the proper position, resulting in imbalances throughout the body. When imbalances occur, normal gait is altered and compensations, such as limping, arise. When posture and biomechanics are affected, injury is the most common result.
A flexibility example for runners is tight calves. Frequently, tight calves stem from poor gluteal activation. In turn, the inflexible calf muscles restrict the degree of dorsiflexion at the ankle (i.e. the ability to raise the ball of the foot and toes toward the ceiling for proper running mechanics). Poor dorsiflexion causes the runner to pronate (tilt the foot inwards upon landing), which can lead to shin splints and Achilles tendonitis.
Why are Runners So Inflexible?
As a group, runners are widely known as inflexible athletes (both in terms of muscles and in terms of daily lives.) Running in itself, however, precludes itself to inflexibility. Unlike other sports, such as basketball or soccer, runners utilize repetitive movement in the same plane in order to complete their workouts and races. This one-track movement leads to natural muscle imbalances, because it overdevelops muscles that are required for forward motion, while neglecting the muscles that are necessary for moving backward or side-to-side.
Additionally, injury – both acute and severe – can reduce the flexibility of a muscle. When a runner experiences a muscle strain, the surroundings muscles will tighten in order to protect the damaged area. Runners also develop scar tissue in muscles that sustain damage, which can lead to overall muscle shortening.
Additionally, even the slightest biomechanic abnormality can result in muscular imbalance which only further perpetuates poor flexibility. Muscle and tendon impingements, restrictions, and entrapments are all fairly common for runners (particularly if a muscle imbalance is also present).
The mentality of runners might also be to blame for poor flexibility. In other sports, the role of flexibility is widely established. However, contradicting research on stretching1 (ultimately an activity that is viewed as time consuming) provides runners with a seemingly valid excuse for ignoring range of motion exercises.
Flexibility and Injury Prevention
Given the manner in which joints move, it should be no surprise that enhanced flexibility (not to be confused with laxity) is important for injury prevention2. However, a number of studies have contradicted this statement, asserting that poor contractility of muscles and tendons surrounding a joint does not reduce injury risk, and may instead be beneficial.
While this may indeed be true for a person with perfect biomechanics and a complete absence of muscular or structural imbalances, it is difficult to make this assertion for the general public.
For instance, many of the most prevalent running injuries directly stem from lack of flexibility and range of motion. These include:
• Shin splints
• Runner’s knee
• IT Band Syndrome
• Hamstring Tear/Strain
In each instance, a muscular imbalance can be to blame. As an example, the kneecap is held in place thanks to equal and opposing forces placed on it by the quadriceps muscles, calf muscles, IT band, and hamstring muscles3.
When one of these muscles or tendons becomes too tight, another muscle must compensate. In runner’s knee, compensation leads to the kneecap becoming off-track, causing pain. Maintaining proper elasticity in the lower leg muscles is one way to prevent the occurrence of runner’s knee.
Range of Motion and Performance
In addition to flexibility and injury prevention, enhanced range of motion is necessary for running performance. The simple act of running requires a number of joint movements. For instance, dorsiflexion occurs at the ankle, while the leg bends at the knee for forward propulsion. Movement in the hip joint drives the knees upwards. Flexibility in the hallux (big toe) joint is necessary for propulsion from the balls of the feet.
While emerging research has suggested that flexibility and running economy are inversely related4, sufficient range of motion is, at a very basic level, necessary for performance. The athlete that can drive his or her knees higher, maintain dorsiflexion for a longer period of time, and maintain elasticity in the hips throughout a race is more likely to outperform the athlete whose range of motion and subsequent biomechanics are negatively affected by poor flexibility.
While it is true that muscles act as a spring for stored energy, there is a fine line between optimal range of motion and tension within the muscles, and restricted range of motion and impaired performance.
In fact, a subsequent study showed that muscle fiber elasticity is truly what is important when it comes to running economy and flexibility, not limited range of motion as the running economy study suggests. This study found that elite runners are more likely to have the COL5A1 gene5, which causes inelastic muscle fibers. Note, however, this simply means that the fibers within the muscles themselves are able to store more elastic energy. Ideally, a runner will have full range of motion while possessing optimal energy storage within the flexible muscles.
How to Improve Flexibility
If your flexibility is lacking, there are a number of ways you can improve your range of motion over the long term.
Dynamic stretching is perhaps one of the most commonly prescribed flexibility activity for runners because it also strengthens muscles in a functional manner. This type of exercise activates the muscles that will be used for running while also enhancing range of motion. Dynamic exercises should be performed prior to exercise. The most beneficial dynamic stretches for runners include leg swings and form drills, such as A-skip, B-skip, and C-skip.
Static stretching, which involves the holding of stretches for prolonged periods of time, should not be performed before exercise. Researchers have determined that static stretching prior to running can hinder endurance while increasing the energy cost of running, both of which lead to impaired performance6. Dynamic stretching, on the other hand, does not have the same consequences7. The best time to perform static stretching is immediately following a run.
The foam roller is a tool that runners love to hate. This cylindrical roller made from dense foam is utilized primarily for self-myofascial release but has also been shown to improve hamstring flexibility in as little as four weeks8.
Range of Motion Exercises
As previously mentioned, range of motion is important for performance. However, how can range of motion be improved? A series of exercises exist that are designed specifically for the unique needs of runners. When performed both before and after a run, this fifteen minute series of exercises, which targets all of the major and minor muscle groups utilized during running, can improve flexibility and performance in 3 weeks.
A great preventative measure for combating muscular restrictions, adhesions, and limited range of motion is sports massage9. Over the long term, sports massage has been shown to improve flexibility and range of motion while also aiding in injury prevention.
1. Judge, L. W., Petersen, J. C., Bellar, D. M., Craig, B. W., Wanless, E. A., Benner, M., & Simon, L. S. (2013). An Examination of Preactivity and Postactivity Stretching Practices of Crosscountry and Track and Field Distance Coaches. Journal of Strength and Conditioning Research, 27(9), 2456-2464. doi:10.1519/jsc.0b013e318257703c Link
2. Johnston, C. A. M., Taunton, J. E., Lloyd-Smith, D. R., & McKenzie, D. C. (2003). Preventing running injuries. Practical approach for family doctors. Canadian Family Physician, 49, 1101–1109. Link
3. Messier, S. P., Legault, C., Schoenlank, C. R., Newman, J. J., Martin, D. F., & DeVita, P. (2008, November). Risk factors and mechanisms of knee injury in runners. Retrieved May 29, 2017, from https://www.ncbi.nlm.nih.gov/pubmed/18845979 Link
4. Jones, A. M. (2002). Running Economy is Negatively Related to Sit-and-Reach Test Performance in International-Standard Distance Runners. International Journal of Sports Medicine, 23(1), 40-43. doi:10.1055/s-2002-19271 Link
5. Posthumus, M., Schwellnus, M. P., & Collins, M. (2011). The COL5A1 Gene. Medicine & Science in Sports & Exercise, 43(4), 584-589. doi:10.1249/mss.0b013e3181f34f4d Link
6. Wilson, J. M., Hornbuckle, L. M., Kim, J. S., Ugrinowitsch, C., Lee, S. R., Zourdos, M. C., . . . Panton, L. B. (2010, September). Effects of static stretching on energy cost and running endurance performance. Retrieved May 29, 2017, from https://www.ncbi.nlm.nih.gov/pubmed/19918196 Link
7. Zourdos MC, Wilson JM, Sommer BA, et al. Effects of dynamic stretching on energy cost and running endurance performance in trained male runners. J Strength Cond Res. 2012;26(2):335-41. Link
8. Junker, D. H., & Stöggl, T. L. (2015). The Foam Roll as a Tool to Improve Hamstring Flexibility. Journal of Strength and Conditioning Research, 29(12), 3480-3485. doi:10.1519/jsc.0000000000001007 Link
9. Brummitt, J. (2008). The Role of Massage in Sports Performance and Rehabilitation: Current Evidence and Future Direction. North American Journal of Sports Physical Therapy : NAJSPT, 3(1), 7–21. Link