Mobility Checkpoints for Runners
“Running isn’t bad for your knees. Maybe your knees are bad for running.”
Today’s blog post comes from Dr. Drew Martinow. Dr. Martinow is a chiropractor located in Eastern Canada who works with athletes of all ages. He’s an alumnist of Brock University and Canadian Memorial Chiropractic College. Drew grew up playing and continues to play baseball. He’s known as a feared right handed closer who can grow the best playoff beard around.
As Canada begins to slowly re-open due to the Global Pandemic, it is common that many commercial gyms are still closed or are operating at a diminished capacity. This has forced many individuals to take an alternative approach to their fitness. For many, running/jogging has been incorporated into their weekly routines. Running is one of the oldest sports or forms of movement that dates back thousands of years. We have evolved over time to be very efficient bi-pedal movers. However, when beginning this journey, there are some movement pre-requisites that can help ease the transition into regular running. The purpose of this article is to briefly outline the running gait cycle, focus on the movement pre-requisites of the joints involved and how these relate to running injuries.
Running Gait Cycle
The running cycle is slightly different than the typical walking gait cycle. The running gait cycle consists of the stance phase, float phase and the swing phase. The float phase is what differentiates the running gait from walking. The gait cycle is a series of movements that begins with the foot’s initial impact with the surface until it reconnects with the surface at the end of the cycle. With running, the stance phase accounts for less than 50% of the cycle. The swing phase is greater than 50% of the cycle and causes an overlap of the phases which explains the float phase. Running requires a larger range of motion in the lower extremity joints involved which include the foot, ankle, knee and hip. Running also requires a greater amount of eccentric muscle contraction than walking because of the higher impact forces.
The Stance Phase
This phase begins with the footstrike, then midstance and finally take-off. With the footstrike, the purpose is to absorb the impact of the landing. Key joints involved include the subtalar joint, which is a multiplanar joint that allows for pronation as well as the talocrural joint which allows for dorsiflexion of the ankle. As the stance phase continues to midstance, the foot will move from pronation to supination in preparation of take-off. An important addition is distinguishing between the different footstrike patterns. You can have a heelstrike pattern (landing on the heel), midfoot strike pattern or a forefoot strike. Often times the type of shoe used will impact the type of footstrike. People who wear more traditional running shoes tend to heel strike more whereas runners who wear a barefoot-type shoe tend to midfoot or forefoot strike.
There is a good reason why barefoot runners use midfoot or forefoot strike. It is more efficient when transferring the forces up the kinetic chain. When landing on your heels, it’s almost as if you are “touching the brakes” with each step. A heel strike pattern in barefoot runners may have an increased risk of stress fracture injury due to the way the forces are absorbed.
The Swing Phase
The swing phase occurs when the lower extremity swings through the air from take-off to footstrike. As take-off occurs, rectus femoris (quadriceps muscle) and tibialis anterior (front shin muscle) muscles are the most active. During the late swing phase, the hamstrings and hip extensors are active. It is important to note that during both the stance and swing phase of running, the adductor muscle group (groin muscles) are active.
Mobility Checkpoints
Here I have outlined the top 5 mobility checkpoints or movement pre-requisites that any runner, either recreational or competitive should work to maintain. In the next section we will break each one down as to why they are important.
1. Big Toe Dorsi-flexion
2. Ankle Dorsi-Flexion
3. Ankle Pronation-Supination
4. Hip Flexion/Extension
5. Adductor Tissue Mobility
Movement Pre-requisites
1. Big Toe Dorsi-flexion
When propelling forward into the swing phase, the last part of the foot to touch the ground should be the big toe. Having enough active and passive range of motion in the great toe allows the weight distribution to go directly over the middle of the foot when leaving the ground. Having a lack of great toe dorsi-flexion would cause the force to be distributed to either the inside of the foot or through the outside part of the foot. This can lead to a number of changes further up the kinetic chain. So, make sure that big toe is able to move adequately to ensure an effective toe-off propulsion. Without proper big toe mobility, it could lead to tendonitis or planar fasciitis.
2. Ankle Dorsi-flexion
When running, up to 3 times the weight of the body is absorbed by the lower extremity every time it lands. Therefore, the foot/ankle need to act as a shock absorber, a lever arm to propel the body forward and a balance board when running on uneven surfaces. This is facilitated largely via the ankle, specifically the subtalar and talocrural joints. Ideally at footstrike, the ankle should be at about 90°. This will allow for 20° of dorsiflexion from neutral throughout the stance phase. Dorsiflexion paired with pronation is critical for shock absorption. Lack of dorsi-flexion could lead to achilles tendinopathy or hamstring strains.
3. Ankle Pronation-Supination
The subtalar joint primarily allows for pronation and supination (allowing the foot to turn inward and outward). Pronation allows the foot/ankle complex to act as a shock absorber, while supination is the lever arm for propulsion at toe off. Adequate pronation is essential to allow for flexibility in the foot/ankle to accommodate for different running surfaces. The stance phase ends with the foot supinating to create propulsion at toe-off (ideally through the great toe). Supination creates stiffness in the foot/ankle complex which allows for a more effective propulsion at toe-off. Overpronation can lead to a number of injuries such as patellar tendonitis, shin splints or an achilles tendinopathy. Over supination can lead to peroneal/fibular tendinopathy.
4. Hip Flexion-Extension
Hip flexion/extension range of motion changes dramatically with the type of running performed. As velocity increases, the hip increases its flexion range of motion. At footstrike, the hip can be flexed up to 65° in swing phase and extend to 11°. This clearly depends on the individual and speed of running. The hip abductors and adductors (glutes and groin) muscles co-contract to provide stability of the stance leg during single leg support. The hip will have peak extension at toe-off which is facilitated primarily by the gluteus maximus. The hip will go through about 40° of range of motion (flexion to extension) in recreational runners, and can be as much as 60-65°in elite runners. Without proper hip extension, there is a chance that the extension needed will come from either the joints above or below. It is very common to see limited hip extension and greater low back extension to compensate. This could lead to low back pain while running or the chance of losing the proximal stability that is required to maintain distal mobility.
5. Groin Mobility
As we have discussed earlier, the adductor or groin muscles are constantly working throughout the entire running gait. They are unique because they work not only to stabilize the pelvis throughout the running motion, but the hamstring portion of the adductor group also acts as a hip extensor. Having adequate adductor mobility (not flexibility) is important to ensure that the pelvis, sacrum and the low back is stabilized throughout the running gait. The proximal stability allows for the distal joints (hip, knee ankle, foot) to do their job more efficiently. Too much hip adduction (tight hip adductors) could lead to Iliotibial band syndrome or stress fractures.
Take Home Points
1. Foot and ankle care SHOULD be a priority. Continually working on maintaining or improving active range of motion and control of the ankle/foot complex is a MUST for optimal performance.
2. It’s all in the hips. There is a need for proximal stability in order to achieve distal mobility. Keep up with the adductor group in all ranges of motion and make sure you are getting adequate hip flexion/extension in your stride.
3. If you are new to running or a consistent runner, being assessed and evaluated to see if/where your weak links are can be very beneficial in order to keep racking up those miles.
References
1. Nicola TL, Jewison DJ. The anatomy and biomechanics of running. Clinics in sports medicine. 2012 Apr 1;31(2):187-201.
2. Sueki DG, Cleland JA, Wainner RS. A regional interdependence model of musculoskeletal dysfunction: research, mechanisms, and clinical implications. Journal of manual & manipulative therapy. 2013 May 1;21(2):90-102.
3. Kibler WB, Press J, Sciascia A. The role of core stability in athletic function. Sports medicine. 2006 Mar 1;36(3):189-98.