This is a relatively common occurrence for individuals who are changing from a heel strike form to a mid of forefoot strike form.
My first question for any runner who is changing form is: why? There are several reasons that runners will often give such as injury problems, advice from runner friends, performance, reading about it online, and many more. Ultimately, I’m a proponent of only changing form when it “needs to be changed”. Over our lives as children into adults, we all develop a natural and personal running form. Some of this form is taught, but most of it is the natural way our body decides to move. Over this same course of time, our body tends to become proficient in this running form – it expends as little energy as possible to move you as far/fast as possible. These proficiency changes largely occur in neurological adaptations along with very specific and local musculoskeletal adaptations. For example, as a runner completes more running, certain parts of a bone will be reinforced based on the amount of force that part of a bone has to absorb. Over time, the bone will become “stronger” in the location that is stressed by the running.
Form change has been a big deal over the last few years and has actually stayed around a bit longer than the big wave of minimalist/barefoot running that was very strong a few years ago. Sometimes form change can be positive and needed, but other times it can be detrimental and could lead to injury. I once worked with an individual who had to stop running for several years due to chronic calf/achilles issues. This runner decided to make a comeback and wanted to have help, so he hired a coach. The coach was a huge proponent of forefoot striking and encouraged this individual to adopt that pattern. Forefoot striking has been shown to increase the load on the calf/achilles, and the runner suffered from even worse achilles pain during his comeback. This is an example of how form change can go wrong.
So, ultimately the #1 question for anyone going through or considering form change is: why?
For this particular question that was submitted, the foot pain is a somewhat common occurrence with a switch from a heel to a mid or forefoot strike pattern. Studies have shown that mid and forefoot strike patterns increase the load on the calf/achilles along with the load on the metatarsal bones in the foot (likely what the questioner is referring to). As a rule of thumb, bone stress injuries (i.e. shin splints, stress fractures, and everything in between) for heel strikers occur more regularly in the shins and for forefoot strikers occur more regularly in the feet. Thus, it is likely that the pain is related to a stress injury of some sort … hopefully on the end of a stress reaction vs a stress fracture.
If deciding to make a change in form (for good or “bad” reasons), what can be done to avoid the risk of injuries like this? #1 is a very gradual easing in period to the new form usually occurring over months. #2 is strengthening of the areas that are going to be working harder with a form change.
Most studies that have looked at transitioning to a significantly different form and/or transitioning to a significantly different footwear (i.e. minimalist) have resulted in recommendation of a gradual transition over 4-8 weeks; however, no consensus really exists at this point. To illustrate this type of transition, it could be that you set up to do 10% of your volume at a forefoot strike for the 1st week and then add 10% per week until you are running all of your volume with that foot strike type. The reasoning behind this transition period is to allow the bones, joints, muscles, etc. time to adapt to the new demands placed on them.
For strengthening, I would recommend several different foot and ankle exercises such as: toe yoga (isolated control of toes in various ways), towel scrunches, double or single leg heel raises, bent knee heel raises, and maybe some plyometric exercises either before or during the transition period noted above. Sets and reps are pretty individualized but I would likely be heading toward 50+ reps for the exercises above to be done at least 3 times/week if not daily.
Hope this is somewhat helpful. Switching form is always tricky and should always be approached with clear intent and caution!
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