One day while teaching a private session one of my students brought in an old book of stretches and stretching routines and asked which ones were best for swordplay. The book she brought is an excellent resource and I snapped a couple pics of one routine to pass along on the blog (the book itself is unfortunately out of print).
The stretching routine I chose was for tennis. Tennis is an excellent analog for swordplay particularly when focusing on one handed swords (golf stretches are a good alternative for two handers like the longsword). Many of the motions in tennis are similar, an emphasis on footwork and extension, carrying the weight on the balls of the feet, core rotations, and a lot of shoulder work.
Take a look at this stretching routine for some guidance on forming your own. I recommend taking at least 10 minutes after any fencing practice to do some stretching to not only prevent stiffness but to increase your range of motion. Stretch is easier when you’re warm, so don’t wait till you get home. If you do wait till you get home, put on a nice hot shower and stretch there (however make sure you don’t leave your shower for a cold apartment and stiffen up, put on some warm clothes or a heating blanket to prevent after heat contraction).
Another useful tool for your stretching routine is your smartphone. There are stretching and yoga apps for iPhone and Android. The program that I use is Seconds. It’s a highly customizable timer program that can be easily setup for a guided stretching routine (with text-to-speech for commanded stretching).
To keep up the swordplay, keep up the stretching!