go you! The reason you are sore after running is that it is a considered a weight bearing muscle and uses more muscles than biking which is not considered a weight bearing exercise.

I am trying to start running as well as cross training for biking. Although I can do jogging intervals on the elliptical or treadmill, I'm finding the transition to outdoor very slow so like you I am doing one minute walk run intervals. Sadie the corgie who comes with me as I combine this with her daily walk, is not amused.

marni