Has there been any discussions, articles, or studies investigating the negative impact that intense cycling can have on one's running performance? (Or the other way around..) Obviously, if you took the 2:07 marathoners and had them incorporate 200 mi/week on the bike, they aren't going to be 2:07'ers anymore. Same goes for taking Fabian Cancellara and having him run 70 mi/week, he will bike slower. I'm obviously concerned with the medium, in between these two extremes!
My thoughts are if you’re going to be a triathlete then you need to train in all three (3) disciplines.
Tri’s (imo) are setup for success in your training and race execution. While I believe you will not win a race from the swim. I do believe you can from the bike. Swim fitness will give you a better bike and bike fitness will give you a better run. I do believe that more time is need in bike training, especially for the longer distances.
Examples of my Ironman bike training. This is per late into my long distance build. I will do a over mileage say 125-130 mile single ride follow by day off the bike, then 30-40 miles ez, 60-70 tempo and then 30-40 miles ez.