It's happened three times over the last five months. Nothing major, but definitely a pull. Same leg, same place, in the belly (aka- midpoint) - of the hamstring, not at the attachment to the arse. After a couple days of rest and then a couple days of easy stretching it feels fine. I have surfed lots and it only got tweaked surfing once about three weeks ago during a really choppy day of mosh. I hurt it the first time running through a lightning storm to my car from a bar, the second time a month later doing a front snap kick. I do yoga twice a week, tai chi every day. On the negative side, I work at a desk job seated 6-8 hours a day. I stretch every hour. Any tips. I'm scared next time I'll get a bad one and be out of the line up for a while, just when wave season is ramping up. I know I've come to the right place. My bad shoulder is almost like new due to saged advice received from this here surf predictin site. Thanks in advance!