I run - started with the C25K program which is awesome, and now I am running 4-6kms every few days and aiming to do a 10 km run in October. Even walking 40-1 hour every second day will boost your metabolism. I also use dvds, Jillian Michaels ones are awesome - Ripped in 30 and 30 day shred are great - they are quick 20 min sessions or Extreme Shed and Shred is great - that is a 30 or 60 min one. Really good and all you need are some hand weights.