It's FAST too, in terms of calories burned per minute. I love cycling - but any bike ride under an hour isn't really worth the time, unless you're doing hard

It's FAST too, in terms of calories burned per minute. I love cycling - but any bike ride under an hour isn't really worth the time, unless you're doing hard intervals or climbing a really steep hill. If you have 30 minutes, there's nothing more efficient than running.