A calf strain affects one of the three powerful muscles in the lower leg. You might find that the strain begins as a dull ache and stiffness in the muscle, which gradually worsens during the course of a run or series of runs. Alternatively, you may be brought up short by a sudden, intense pain in the calf when you put in more effort. However the injury starts, your first action should be to apply the RICE procedure (see Running Injuries article for details), before seeking professional advice from a qualified physiotherapist. A calf support sleeve will provide compression. Depending on the severity of the muscle tear, you may have to rest completely from running for 7-14 days. Massage treatment and lots of stretching will speed up the recovery process. Even after rest and treatment be very cautious about resuming running – you may be able to walk, swim and cycle without any discomfort, but the action of running will cause any remaining scar tissue to tear again and you are back to square one. As over-pronation can also be a cause of calf strains, it may be worth investing in a pair of support running shoes, a flat foot support or orthotic insoles to align the lower leg correctly.