The Top 3 Triathlon Metrics Most Triathletes Ignore But Shouldn’t – Part II

Yesterday I introduced the first of three triathlon metrics many triathletes are ignoring but shouldn’t: Functional Threshold. This is a key data metric athletes need to know to improve power capabilities in order to optimize their training and performance.

The second key metric the triathlete in training should be paying attention to is their Bike-to-Run Factor (B2R). TriDot uses this key data point to effectively and efficiently train athletes in the bike and run disciplines for the best and most optimized results.

As many of you know, half and full distance IRONMAN triathlons are bike and run discipline heavy. If your focus is on long course triathlon, the Bike-to-Run Factor is an especially essential triathlon metric.

Bike-to-Run Factor is the relative strength of an athlete’s bike ability to run ability. There are three components to the ratio: 

A. Performance Difference (Bike v Run):

TriDot evaluates the athlete’s performance and current functional threshold (see yesterday’s blog that features Functional Threshold) ability between the two disciplines. We closely monitor and evaluate your performance difference between bike and run using your TriDot Scores and the associated threshold data for each discipline.

B. Sport Age in each:

The sport age gives insight into an athlete’s durability, prior adaptation, and ease of getting back to a prior fitness level. In other words, the Sport Age takes into account previous injuries, how long it takes you to obtain a specific level of fitness, and how long it takes you to reach that level after a certain amount of time off.

C. Functional Threshold Heart Rate (FTHR) in each:

The difference between the two FTHRs gives insight into how intense the athlete’s bike and run threshold abilities are relative to each other. The FTHR ratio determines what kind of heart rate differences will occur when switching from bike to run during a race.

All of these components are evaluated against expected differences based on the athlete’s age, body composition, and so forth to make optimal decisions related to how much training focus to put on the bike and run in order to get the most out of each hour of training.  

The Bike-to-Run Factor determines what type of focus will contribute best to your overall bike/run improvement. Without it, it’s just guesswork for triathletes to determine whether they should train with more volume, more intensity or more frequency.

One of many steps TriDot takes to take this guesswork out of training is by not ignoring the importance of the Bike-to-Run metric.   

Tomorrow, we’ll discuss the third triathlon metric most triathletes are ignoring but shouldn’t: Race Execution Percentage (RaceX %).


TriDot’s predictive analytics approach ensures you account for the Bike-to-Run Factor, one of the three key triathlon metrics often ignored by triathletes, to enable you to have the best race day performance possible. 


Do you consider the B2R an important triathlon metric? What questions do you have about this data point?

JARED MILAM is a professional triathlete, TriDot coach, and member of the Tri4Him Pro Team. He has 16 years of competitive running experience and 11 years of competitive triathlon experience with a half Iron PR of 3:59 and a full Iron PR of 8:30. Coaching under the TriDot system since 2011, Jared loves working with aspiring triathletes of all ages and performance levels.

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