How to strengthen it:
When strengthening your calves, you are probably familiar with regular calf raises. These are great exercises however, when doing calf raises most people only do them with their legs straight. These are great for strengthening the outer muscle (gastrocnemius) and therefore good for sprinters. However, to target the soleus muscle (the distance muscle) we need to do calf raises with our knees bent. You can either do this seated in a chair or adopt a wall sit position and lift your heels up.
Start with these exercises then progress to single leg calf raises (knees bent and straight) and progress to adding weights to replicate the loading we absorb when running.
Calf strains are very common in runners, so strengthening these muscles it will reduce your risk of muscle strain or tear.
Try adding straight leg and bent knee calf raises into your strength and conditioning regime to prevent injury. Or chuck a few in when brushing your teeth!