This afternoon I got on the treadmill for an hour hill/tempo workout. The first 1/2 hour I walked at 3.5 mph on a 15% incline. Then for the next 15 minutes I lowered it down to 1% and ran at 8 mph (7:30 pace). And for the final 15 minutes I walked at 3.5 mph on a 15% incline. Towards the end I could tell that I was giving my legs a good workout!