After Sundays ride I noticed a lump on my calf muscle it is round and obvious when the musckle is tensed. It is about 5mm high and the size of a 10p. There is no pain when pressed but it does not go away, it feels smooth and does not seem to be a problem. Could it be just a knot in the muscle or another type of injury, I played reasonable club rugby for many years and do not recall seeing a similar bump. Is this something anyone else has encountered?