Cycling Characteristics of Female Triathletes Qualifying for the 2022 Ironman World Championship

Having tested many female triathletes in late 2021 and early 2022, I looked for trends among those who targeted qualifying for the Ironman World Championship in the same year.

First, the info provided below is by no means definitive data claiming that to compete at the front of the female age group ranks, an athlete must have 'x' or 'y' characteristics.

The goal is more an exercise of personal curiosity and to identify some traits of female amateurs performing well at the top of their respective age groups. This info may interest athletes and fellow coaches alike.

I'll discuss concepts like lactate accumulation, intensity domains, inflection points like 1st and 2nd thresholds, etc. If you are unfamiliar with those concepts, below are two great resources:

Training Zones - by Endurance Essentials

Lactate Testing for Athletes - by Upside Strength

With that out of the way, let's dive into the data. For this review, I included the data of female triathletes I knew from the testing they were pursuing a Kona slot. In addition, I looked at the data between October 2021 & August 2022 to include popular late calendar North American races such as Ironman Florida, Cozumel & Arizona, and the late calendar races offering slots for the 2022 world championship.

Of around 40 female triathletes tested, 30 were pursuing a championship spot & 80% achieved their goal. Below is a breakdown of the age group placing for those earning a sport for the championship

The first thing I looked at was the relationship of blood lactate accumulation at their first inflection point (known as 1st Lactate Threshold or LT1) for those that qualified in the age groups between 30 and 55 years old. From all, 75% with a lactate accumulation of 1.6 mmol/L at LT1 earned a Kona slot, and 25% with a lactate accumulation between 1.7-1.8 mmol/L at LT1 earned a slot. In contrast, non of the females I tested with a lactate accumulation of 1.9 mmol/L or higher at LT1 earned a slot.

Part of the reason is the relationship between the power or heart rate athletes achieved at LT1 with their durability to sustain an intensity near LT1 for 112 miles without negatively impacting their run performance. (more on this below)

Depending on the athlete's fitness, it has been my experience that top age groupers can race at/near LT1 (within ~10 watts power-wise or ~5bpm heart rate-wise), particularly for those that can achieve an LT1 at ~1.5mmol/L (+/-). On the other hand, the higher your lactate at LT1, it suggests the lower your durability to sustain the intensity.

Therefore, those athletes either need to ride at a lower intensity to run well off the bike or ride near LT1 but risk struggling on the run.

Next, to add more context, below is a table showing lactate accumulation at LT1, and LT2, the power in watts per kilogram for each inflection point, and the delta between those.

As you can see, the average power at LT1 was ~ 2.7 w/kg, although those competing at the front of their age group were ~3 w/kg or higher. For instance, the 2022 Age Group 40-44 Ironman World Champion has a power of ~3.5 w/kg at LT1.

Regarding power at LT2, the average was 3.4 w/kg, with the lowest being ~2.9 w/kg. Those competing at the front of their age group were ~4 w/kg or higher. Finally, the delta average between the LT1 and LT2 power was ~23%

From those earning a slot placing in 4th place or lower, the average delta was ~25% or higher, while for those placing 1st to 3rd, the average delta was closer to 21%.

One way to interpret this could be that an athlete's durability to sustain a higher power at LT1 is not necessarily affected by his/her ability to produce power at LT2. In other words, an athlete may maintain a higher w/kg at LT1 despite a high -OR- low w/kg at LT2. And why, for Ironman triathletes, improving your power/speed at LT1 is more specific for the distance demands than emphasizing increasing one's LT2 power/speed.

Of course, LT2 can also be an important marker to improve for some individuals racing Ironman. For instance, those who either won their age group qualifying for Kona or performed better at the championship have higher power at LT1 and LT2.

Also, those at the front of their age group exhibited a higher w/kg at LT1 with a lower lactate accumulation, allowing them to race closer to that marker. For instance, I have race files for three athletes that all won their age group qualifying for Kona. The fastest rode 4% lower of her power at LT1. The 2nd fastest rode 6.5% lower of her power at LT1. And the 3rd fastest rode 5% lower of her power at LT1.

In contrast, I only have race files for 2 of the athletes that place 5th or lower in their age group when qualifying for Kona. For those two athletes, while their lactate accumulation was ~1.6 mmol/L, their w/kg was between 2.5-2.8 w/kg. And their average power on race day was ~9% lower than their power at LT1.

An important thing to notice is that for age groups between 30-49 y/o, a higher w/kg at LT1 with a lower lactate accumulation (<1.8 mmol/L) is an important characteristic when competing at the front of their respective age groups. However, this seems less vital for age groups 50 and over as athletes with a lower w/kg and a lactate accumulation <1.8 mmol/L at LT1 can still perform very well as those age groups may have fewer total participants.

In summary, for the 2022 season, some of the ingredients female triathletes needed to compete at the front of the 30-49 age groups cycling-wise were:

1. A lactate accumulation of ~<1.7 mmol/L at LT1.

2. A w/kg of 2.9> at LT1

3. A LT1/LT2 delta of ~21%

Next post, I'll review the female running testing data and discuss possible trends between their bike vs. their run metabolic profiles.