Originally Posted by
jordo_99
The whole point of tri-specific bikes is that they can be set up to use different muscles (run with calves and bike with thighs?) on the bike to try and keep your running performance at it's best.
Actually, this is one of triathlon's biggest perpetuated myths.
One of many links about this:
http://www.beginnertriathlete.com/di...256257&start=1
You are aero, so it utilizes less muscle power to maintain a given speed, which saves more of your legs for the run. But it doesn't use any different leg muscles.