Theres nothing like a new toy to get you going again. I bought a skipping rope before I went to Sri Lanka, thinking it would help with running technique, I had a couple of skips with it humming the rocky theme tune to myself, and found it was pretty hard work. It really shows up your technique too.
I thought I would show what happens to your heart rate when doing high intensity exercise. It takes quite a while for your heart rate to increase even when you are working really hard, this is why I use power on my bike.
Sometimes when you are going uphill, by the time your heart rate has kicked in you have already burned a match, its also really useful for gauging your rate of perceived exertion as you can instantly see what your power is, (how hard you are riding) before you start getting out of breath. It is good to use several methods of determining how hard you are working, so that you stay in touch with your body.