This sensation of tightness in the calf muscles is very common, particularly in those of you that run. There are many possibilities as to why this may be but most commonly it’s due to weakness in the muscles that bring the foot closer to the shin, the dorsiflexors.
Dorsiflexion is a critical movement for both running and walking. In fact you must be able to get the ankle to neutral (o degrees) if you even want to stand up straight.
By improving the contractile capability of the muscles that dorsiflex the foot, you will see an immediate release of the plantarflexors or calf muscles. When there is weakness in muscles on one side of an axis (in this case the ankle or talocrural joint) there will be a corresponding tightness on the other side of the axis to keep the joint stable.
Try this simple exercise to improve ankle range of movement and reduce calf tightness. Sit on a chair with your legs out in front of you and just a small bend in the knee. Dorsiflex both feet and decide which one is more restricted. Invert the foot of the most restricted side (take the sole of the foot towards the midline) and then holding that inversion, gently pull the top of the foot towards the shin. Hold that contraction for 6 seconds and then relax. Repeat 6 times.
Now evert the same foot (take the sole of the foot away from the midline) and again gently pull up towards the shin. Hold for 6 seconds then relax. Repeat 6 times.
You should see an immediate increase in range of movement and a reduction of any tightness in the calf muscles. Repeat on the other ankle if you now have more range on the previously restricted side.