Considering all of the positive points you made regarding riding the bike, I wonder why you are torturing yourself by running... unless you like that kind of thing.
I am in the Army Reserves. I must run 2 miles 1 time a year for time. (I have 17:30 minutes to complete this)
Anyhow as we know that running is different than biking, so if you have to run you must practice that at least once in a while.
Though I would like to do most of my cardio work on the bike!!
I just wanted to know if you can get as much out of Biking as running.
I think that you can: (My wife who does triatholons say that you can not get as much out of biking as running. I disagree with her(Yikes

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