If you really enjoy gardening you don't like to stop and go in the house for a rest even if your back is bothering you. However, that is a big mistake. Your back is giving you a warning it needs a rest and if you just ignore it you will probably just damage it even more. If you are having back problems here is a good source of information. It is on a back surgery site but has a really nice collection of good articles on preventing and easing back pain.
www.herniateddiscbacksurgery.com
www.herniateddiscbacksurgery.com