Getting a little extra exercise

I took my son and a friend to the local skate park for an hour this afternoon. Instead of just standing and watching (and I can't skateboard), I practiced walking along some of the rails, balancing on them like walking across a tight rope... It was fun, and doing that type of balancing is really good exercise, you're constantly having to adjust muscles in your legs (and if you're me - wave your arms frantically) to stay on.