Someone at Endurance Nation asked about using Best Bike Split to guide minute-by-minute power during the bike leg of an Ironman. Best Bike Split is a web based calculator which takes a number of key variables, and generates both a predicted overall time for the course, and details how to ride the course depending on wind, temperature and elevation changes. The variables include: the elevation map of the actual course to be ridden, rider weight, type of bike used, position on the bike, anticipate speed and direction of wind, temperature, and, most important, key metrics of the rider’s power when riding. It seems like a very thorough algorithm, no? My thoughts:
My opinion on the value of BBS ON RACE DAY…it’s best forgotten. There is no way to pre-program the variables you’ll actually encounter when racing: temperature, wind, draft packs to avoid, aid station jam-ups, pavement quality, etc. etc. Trying to shoehorn on-course performance into an algorithm generated point-by-point power level broadcast on your Garmin head unit would be mightily frustrating, in my opinion.
But then, I believe two interrelated things very strongly. First, racing by perceived effort is the gold standard for achieving the best possible time. However, that assumes one has garnered enough experience at the race distance in question to make intuitive choices properly on a moment by moment basis. And maybe having a tool like BBS is a good way to shorten that learning curve. Second, I also believe that we are not race cars. Meaning, we are way more complex than simply an engine, fuel and speed/power. There are a gazillion things happening in our body at all times, mediated by and communicated about through systems such as endocrine and neurological. Our brain (NOT our conscious mind) has been designed over eons to manage this complex system. A big part of athletic training is to help wire the brain to do that job without much outside interference. I think the human brain/body system is way more complex and smarter than any simplistic algorithm, no matter how many variables it purports to incorporate.
I’ve compared BBS to my race times the past two long distance races, and they were within 3-4 minutes. So it’s a good tool to help me plan my race execution strategy, and keep me honest during the race. But I wouldn’t want to give my decision-making over to it on race day.