what caused this leg injury and how can i overcome it?

[porphyro]

i run about 2 miles twice a week, walk around 3-4 miles per day, and excercise most mornings (crunches, a bit of weight lifting). i have recently cut down on the running but go swimming on average once a week, usually between 60 and 80 lengths. until recently i have felt great benefits from this routine, but of late my left leg sometimes aches so badly it feels like i have pulled a muscle - worst area is hip to upper thigh. sometimes i have an ache reminiscent of "growing pains." resting sounds good, but if i do not get good excercise each day i feel tensed up and unhealthy.
any excercise tips gratefully appreciated!

[Buenchico]

The swimming could well be the cause of the problem, especially if you're using breast stroke, since this can result in a repetitive stress injury (bursitis) to the hip. Try cutting down on the swimming and/or switching to a different stroke.

Chris