Hi, I wen't on a small rollerblading walk with my 8 month old boxer today, we probably went about 2 miles, and by the end of the trip she was exausted! It was a hot day, and I know it was from the heat. My question is, on a nice cool day, how long of a bike/rollerblade trip can she endure? Me and my wife usually go 20 miles on a bike and 5-10 miles on rollerblades, we were hoping to work her up to 20 miles, is that possible at all?