2012 Ironman St. George: Danielle Kehoe’s Bike Split Analysis
The St. George bike course is notorious for its hills, including two solid climbs per loop and over 7000 feet of elevation to tackle. The 112 mile (180k) course began at Sand Hollow Reservoir, looped through the surrounding canyons, and ended in downtown St. George, UT. For Danielle, this was a 6:00:15 chunk of her race day. By no means was this a record setting bike split for an Ironmen competition; however, Danielle was the third fastest female on the bike for the day, with only pro triathletes Jessie Donavan (1st fastest bike split at 5:55:24) and Meredith Kessler (2nd fastest bike split at 5:57:14) finishing the bike faster.
While the bike splits were not amazing simply based on duration, every athlete in this race will tell you that finishing the bike in this race in six hours was nothing short of stellar! With the usage of power meters in training and racing, it becomes much more clear when race conditions play such a huge role in the outcome, showing just how much work the athletes are actually doing. The following is an analysis of Danielle’s bike split, which shows the high effort she was producing to be able to finish with the third fastest time on the bike.
General analysis shows that Danielle averaged 171 watts, a little more than 78% of her functional threshold power (FTP), and 3.14 w/kg, for 6 hours. She had an average speed of 18.46 mph. Because the bike portion of an Ironman is essentially an individual time trial (non-drafting) event, it’s not unusual to see normalized power (NP) fairly close to average power. In the case of Danielle during IMStG, this holds true, as her NP is 180 watts. Her total Training Stress Score (TSS) was 405.7 – a measurement of total fatigue and effort during the race. To put this figure in perspective, a TSS score of 100 means the rider spent 1 hour of riding at his or her functional threshold.
Further analysis shows that Danielle’s power in the first loop of the course was at 180 watts (NP of 186 watts), while her power in the second loop was 160 watts (NP of 168 watts). Note again that average power and normalized power are not very different. A drop in average power of slightly more 11% in the second loop was not ideal, however, in an ironman bike split, it’s quite common to see, especially when weather plays a factor, as it did on this day. Based on the split times of the female athletes ahead of Danielle, it’s very likely that nearly everyone was performing in a similar manner. Additionally, the extreme windy conditions during the first half of the bike died down substantially, which likely altered the athletes’ perception of pacing. Proof of this is shown by the fact that Danielle’s speed was only slightly slower (.14 mph) in the second loop.
Bike Split Summary By The Numbers:
Danielle Kehoe
5’2”, 120 pounds (54.43 kg)
Threshold power: 218 W, 4.0 w/kg
Training Stress Score: 405.7 TSS
Energy: 3660 kj
Average Cadence: 78 rpm
Max Cadence: 170 rpm
Average Watts: 171 W
Normalized Power: 180 W
Max Watts: 617 W
Peak 20 min: 193 W
Peak 60 min: 188 W
Peak 3 hrs: 185 W