Half Ironman 70.3 Bike Times as Percent of Finish Time: The 50% Rule

As you prepare your training plans and consider your racing schedule, if you've got a half Ironman race on the calendar, you're trying to decide how much time to spend swimming, biking and running during the year.

One of the factors that should influence your thinking is this: your half Ironman bike time may very well end up being 50% of your total finish time. Of course, as shown in the chart, there is some variation by race (Brazil, Germany, Mooseman and UK) but for the most part, the 50% rule holds. Same is true for full Ironman races: 50%.