When I'm at the gym, I usually use the elliptical machine to do my cardio stuff. The other day I got bored of walking/running/ellipticalling (I have no idea what the machine simulates), and decided to climb on one of the stationary bikes instead.
I don't really like riding stationary bikes, because they don't really seem to do anything. It certainly doesn't use up calories as fast as some of the other machines, and it just seems too easy to do. I don't know, maybe I was using it wrong. Anyways, I went about 20 miles or so before I just got bored and it just felt like I was wasting my time pedaling.
Then I tried to get up. It didn't work. My legs just said "Nope! Not going anywhere, chump!"
I'd like to publicly apologize to anyone who uses a stationary bike for exercising. I have underestimated you and will go hide underneath my bed in shame.