If you are a sport person, then then the normal reasons why people get affected by lower back pain do not affect you. Sport is one level above common exercise routines like running or swimming and hence you are already doing everything that can be done to keep your body strong and healthy. That being said, you can still invite lower back pain to trouble you by pushing yourself too hard. Just because you take part in sport, it does not make you superman. None of us are, unfortunately, even though it would be fun to be able to leap across buildings and punch through mountains.  

The best solution for a sports person to get out of lower back pain is rest, plenty of it. The other things you might want to try are

i. Drink lots of water to allow your body to repair damage cells and hence muscles in the lower back area.

ii. Sleep a lot until you feel better. We are not asking you to sleep for days together. If your normal sleep duration is six hours, may be eight hours of sleep to help the pain.

iii. You could also try getting massages, with eucalyptus oil for added effect.