Suffering From “Shin Splints”?
By: Megan Piersol, DPT
Are you often or always sore down your shins after walking, dancing, or running? Do you think that it is just because you were on a hard surface? If you answered yes, did you know that you might be able to have more control over this occurrence than you think?
Shin splints are not due to the shin bone itself, but are actually a reaction (often delayed) of soreness from a muscle in the front part of your leg called the Tibialis Anterior. When you exercise a muscle (eccentrically), you develop micro tears in the muscle. This is normally a good thing as this is how muscles rebuild and become stronger. However, if you are doing a weight bearing activity repetitively, with bad form, with poor strength, and/or with bad stabilization, the muscle gets stressed differently and can result in inflammation or irritation of the muscle. Shin splints are common in runners, dancers, and those that try to increase their leg activity too quickly.
Basically, muscles work in two ways: concentric contractions and eccentric contractions. Concentric contractions are when a muscle goes from a longer to shorter position while taking on a load. One example is lifting a mug to your mouth. The bicep is working concentrically to bend the elbow to allow your arm to reach closer to your mouth. Eccentric contractions are when the muscle is going back to a lengthened position while loaded/weighted. This is the opposite motion that the particular muscle does (i.e. the bicep bends the elbow, so straightening the elbow would be the opposite motion). When you are lowering the mug, your bicep is getting longer and having to control the motion slowly so that the arm doesn’t just straighten quickly.
The Tibialis Anterior is a muscle that allows your ankle/foot to dorsiflex. Dorsiflexion is when the foot comes up towards your head. Dorsiflexion occurs when your foot comes off the ground during walking so that the foot clears the surface you are walking on and you don’t trip. The opposite of dorsiflexion is plantarflexion (the motion of the foot downward as if pressing a gas pedal). Plantarflexion is the motion we use to help push off to allow forward momentum when walking, jumping, and running. The foot stays in dorsiflexion from when the foot leaves the ground until the heel touches the ground when walking. If you do not have enough control and strength in the Tibialis Anterior, your foot will fall quickly and slap the ground. Doing this over and over again will create irritation to the muscle. Runners that land on their heel or closer to their heel tend to have more issues with shin splints if they don’t have good ankle strength and eccentric strength of their Tibialis Anterior. Runners that run more towards their mid to forefoot don’t land with as much of a dorsiflexed foot, but still need good Tibialis Anterior eccentric control to help balance out the plantarflexion moments. Harder surfaces may create more irritation than softer surfaces do because of the difference in ground forces.
If the shin pain only occurs when you are doing (or always at a certain point of time in) your activity and stops right when you stop doing your activity, then you may have a problem with pressure building up in the muscle and it is not shin splints. This would be best addressed by an Orthopedist.
Eccentric strengthening is important to help with movements and being able to control movements more fluidly. Having good foot, ankle, hip, and core muscle strength is very important to help support weight bearing activities. This is best built up over time and not advanced too quickly to avoid injuries. Other ways to help with shin splints are to stretch the front part of your leg or use a foam roller or tennis/lacrosse ball to massage the front “shin muscles.” Slowing down or cutting back on your exercise routine will also be beneficial. Going to more low impact activities such as biking, swimming, or elliptical may be best during the recovery period. You should always ease in to anything that is new or when trying to advance to the next level. Increasing mileage of running from just 1 to 2 more minutes versus increasing to another mile may help prevent development of this problem. There are numerous running programs and algorithms out there to help with advancing your mileage in a slow, controlled manner. Having someone look at your running form may also help prevent or alleviate this injury. Landing certain ways on the foot can help disperse forces more evenly versus other landing methods. Some people use compression socks to help until they can develop enough strength, control, and/or form to support their activity demands. Just don’t expect what works for your friend to always work for you. Everybody’s body is different and we all compensate in different ways, thus we may not all need the same exercise routine or intervention. However, a good core, strong hip, good balance and good proprioception (with agility and dynamic support) will go a long way to help prevent this common condition. Do know that if you are trying something new or a new terrain, this condition isn’t uncommon. It is how long it proceeds that determines what you might need to add, cut back, or change, to start moving forward.