Right now, my very favorite song to hike, run, lift weights, workout to is Rudimental- Feel the Love. It pumps me up and gets me going! It's amazing how music can have such an effect on you.
Give it a listen. Hopefully you'll get pumped up too! I'd love to hear what songs make you smile and/or get you going!
http://www.youtube.com/watch?v=oABEGc8Dus0