How To Cross Train

If you haven't heard by now that cross training is an important party of derby then you're not paying attention.  Almost from day one on skates people have been telling me (and probably you) that simply skating won't cut it.  Of course 'cross training' can be taken to mean any number of things and that's where we run into trouble.  How much time do you spend?  What should you do?  How much rest do you need?  I'd like to share what I've been told and what I think.  Cavaet:  I am not a professional trainer and anything you choose to do that may cause you harm or injury is something you choose of your own free will and therefore your own damn fault.
Don't Run Distance
Distance running is a hamstring/calf dependent endurance exercise.  Roller derby is a quad/glute dependent sprint exercise.  Doing one will not help you with the other.  If you must run, do interval training, preferably uphill or up stairs.  Here are a couple of interval workouts I use.  If you don't feel like vomiting when you're done with these you're not sprinting hard enough.  Focus more on moving your legs as fast as possible and less on pushing with a lot of power.  Quick movements with your legs is more important than actually running fast.
Plyometrics
Google it.  I always think of plyometrics as 'constructive jumping around.'  Carmen Getsome has a wonderful DVD with lots of plyometric exercises if you need a place to start.  The nice thing about plyometric workouts is that they wear you out pretty quickly so you get a lot of bang for the time you spend with them.
CrossFit
I'm always wary of new things.  According to Wikipedia (I know, questionable source) there were 13 CrossFit gyms in 2005 and there are 3,400 of them today.  I think of it like buying the very first iPhone on the market.  Yes, you are leading edge, but all that means is you're trying out a product before people get the chance to work out the bugs.  I have heard that CrossFit has a very high injury rate compared to traditional programs.  When they say 'injury' they mean 'broken ankle.'  I already play a sport that dramatically increases my chances of breaking an ankle, I sure as hell don't need to add another one.  I'm not saying that it's not a good program, I'm saying it doesn't meet my risk/reward requirements.
Fast Twitch Muscles
Since derby is a lot of stop and go you want to train up your fast twitch muscles.  You can do this with a speed ladder, sprinting, biking at low resistance and high revolutions etc.  Basically you want to have short bursts where you're moving your body as fast as possible and then rest.  Be sure to give your body a full 48 hours after a fast twitch workout before doing it again.  For me, these never feel like much work because they're so short and intense, but I have noticed a difference in agility after doing them for awhile.
Speaking of cross training - Jet City is lucky enough to have Everett Physical Therapy as a sponsor and I went there for a workout last night before going to skate.  It's nice to have a change from the things I have been doing and the people there were really great about explaining what to do and pushing while still having fun.  BIG like.
<posted on 2.28.12>