It's not unusual for runners who are transitioning from a heel-striking running style to more of a forefoot or midfoot striking style to feel tightness and sometimes pain in the calves. While this is widely accepted as "normal" and "par for the course" in early stages of running with this new technique, it's obviously not desirable!
Why do I now get calf pain? In the case of those who are moving to more of a forefoot or midfoot contact with the ground, calf tightness and pain in the first few weeks of using this new style is due to the changes in the demands on the calf and muscle groups of the lower leg.
Previously when heel-striking, much of the impact and loads were taken through the joints. Now however, with a forefoot or midfoot strike the muscles and tendons are able to better absorb the load, in turn offloading the joints.
This is theoretically better - as long as the muscles and tendons (calf muscles and Achilles tendons in this case) are ready for the task! However, if there is a lack of strength in these muscles and stability around the ankle, the muscles of the lower leg will tighten up and/or suffer an overuse injury.
As well as strength, technique plays a role. If you are too far on to your forefoot (foot pointing down on contact), the calf will experience unnecessary loading.
I use the visualization of landing on the rear aspect of the ball of my foot rather than on my toes to help me get a comfortable midfoot strike.
Another good cue is to see how close you can get your heel to touching down simultaneously with the forefoot - without actually loading the heel.
The other element of technique to think about is where the foot lands rather than simply how. The muscles of the lower leg act as a shock absorber, when over-striding the shock which needs to be absorbed increased significantly. The increased braking forces associated with an athlete over-striding (landing the foot too far ahead of the knee and center of mass) become excessive loads for the calf and Achilles complex to deal with upon contact. If the calves are weak, or prone to injury. This could prove too much.
How can I avoid calf pain? There are a number of things you can do to manage calf pain during this transition period and to avoid excess calf loading:
Calf and Soleus Stretches
Lower Leg Strengthening
Technique Work One smple cue for you to consider:
Focus on bringing the foot down to the ground under a slightly bent knee rather than feeling that you are reaching out forwards with the foot.
foot and ankle massager
Follow A Progressive Program. Make sure you don't do too much too soon, your calves won't thank you for it!