I try and put fitness first these days. I like riding, so I use that most often, but I also run. I really try to make sure I am doing something each day that requires real workout effort (not just a walk and I call that a workout).
Just this weekend, on Saturday, a 55 year old friend of mine dropped dead from a heart attack. He was out of shape, you would even call him fat. He always had mountain dew on his desk, and a few more in the fridge. He always had a bag of some sort of snack around (chips, etc).
He had a wife and two kids. I remember chiding him several times to start some sort of fitness program, to realize what he was doing to himself. he always said he didnt have time. I wonder what he would say now?
I dont think it matters what you do, find a way to get a good solid hour of heart pumping exercise each day, no matter what, and eat accordingly.
Pick something else, and maybe in a month you will miss riding...who knows, just dont stop exercising.