3rd
Rebecca Clarke's scorecard
IRONMAN New Zealand
Saturday 4th March, 2023
Within recommended ranges
Just outside recommended ranges
Significantly outside recommended ranges
81g
Carb per hour
430mg
Sodium per hour
833ml
Fluid per hour
517mg/L
Relative sodium concentration
597mg
Total caffeine
How Rebecca hit those numbers
750ml x PH 1500 (3/4 x tablet)
2 x Gluten Free English Muffins
1 x Serving of Peanut Butter
1 x Banana
1 x PF 30 Energy Gel
*** Review technique if drinking much at this point!
750ml x (1/2) PH 1500 (Tablets)
500ml x PF 60 Energy Drink Mix
5 x PF 30 Energy Gel
2 x PF 30 Caffeine Gel
1.9L x Plain water
1.5 x Energy chew packet with caffeine (48g carb, 100mg caffeine)
1.75 x Energy bar (24g carb)
2.25L x Energy drink (22g carb)
500ml x (1/2) PH 1500 (Tablets)
3 x PF 30 Energy Gel
2 x PF 30 Caffeine Gel
1.3L x Plain water
160ml x Energy drink (22g carb)
320ml x Coca Cola Original
How Rebecca's hydration and fueling went...
- Having claimed 2nd place at IRONMAN New Zealand in 2021, Rebecca returned to the course in 2023 with aims of replicating her podium performance
- After dropping a part-finished bottle of PF60 Drink Mix on the bike, Rebecca did well to adapt her strategy on the fly by utilising aid stations to hit strong carbohydrate numbers and ensure she had energy left in the tank for the run leg
- Despite this, she felt a slight energy lull heading onto the run course, but dug deep to secure a 3rd place finish, averaging 4:40 mins/km (7:30 mins/mile) for a 3:16 marathon
Hydration
- After speaking with the PF&H Sports Science team, Rebecca knew that a strong electrolyte drink before her race would help her to start optimally hydrated. To do this, she chose to drink ¾ of a PH 1500 tablet in 750ml (24oz) of water, rather than the 500ml (16oz) that we would usually recommend. This will have had the effect of reducing the relative concentration slightly and potentially limited the positive impact it would have on her blood plasma volume
- While on the bike, she dropped a half-finished 1L (32oz) bottle of PF 60 Drink Mix, meaning she lost a source of fluid, carbs and electrolytes all at once
- Rebecca tried to combat this from a fluid and electrolyte point of view by picking up plain water and isotonic sports drink from the aid stations, as well as finishing her remaining bottle of PH 1500
- Then, she took a soft flask containing ½ a PH 1500 tablet out of transition with her, which she further diluted using water, sports drink and cola from aid stations along the run course
- Rebecca reported feeling thirsty while running, which may in part have been due to her fluid intake dropping from ~1.1L/h (35oz) on the bike to ~690ml/h (22oz). At the same time, temperatures peaked on course at around 23ºC (73ºF) meaning she was losing more fluid too, due to a higher sweat rate
- Overall, Rebecca consumed ~833ml (28oz) of fluid per hour, with a relative sodium concentration of ~517mg/L (mg/32oz)
- While this electrolyte intake may have been insufficient some ‘saltier’ athletes, Rebecca knows that she’s a ‘low salt’ sweater, who loses just 563mg of sodium per litre (32oz) of sweat, meaning she likely replaced a good proportion of what she lost in her sweat
Fueling
Quick Carb Calculator Recommendation
30g
carb 30 mins before
60-90g
carb per hour during
- After analysing her intake during her win at the Tauranga Half around 6 weeks prior to this race, Rebecca was aware that she would need to increase her carb intake for maximal energy availability on the day
- To help boost her stored energy, Rebecca ‘carb loaded’ in the days before the event, culminating in a race-day breakfast of English muffins with peanut butter and a banana
- Rebecca also topped up her blood glucose levels with a final PF 30 Gel within the last 30 minutes before swim start, to help conserve some of her stored energy for utilisation later in the race
- Confidently leading the race out of T1, Rebecca involuntarily donated ~500ml (16oz) of PF 60 Drink Mix to the bike course due to a bump in the road and had to adapt her fuel plan while riding, deciding to use the on course isotonic sports drink to replace these lost carbohydrates
- Along with her ‘fuel bottle’ which contained several PF 30 Gels and two PF 30 Caffeine Gels, this meant she still hit an impressive intake of ~104 grams of carb per hour while cycling - 59% higher than her intake during the bike at ‘Tauranga Half’ (61g/h)
- Onto the run course, Rebecca initially felt a lull in energy, which may have been caused by slightly mistimed caffeine / carb consumption, combined with the sudden change in muscle activation going from bike to run which can often cause a dip in blood glucose
- She bounced back from this to finish 3rd with a blistering 3:16 marathon time, taking five PF 30 Gels as well as some cola along the way
- Rebecca is going to trial adjusting the timing of one of her PF 30 Caffeine Gels toward the end of the bike leg in her upcoming ’brick’ sessions to see if this helps her avoid experiencing an energy dip at the start of the run in future races
- Overall, Rebecca had a solid average hourly carb intake of ~81g. Especially considering her average intake of 60g per hour at the Tauranga Half just a few weeks prior
- Impressively, despite this increased intake, Rebecca experienced no gastrointestinal discomfort while on the bike, and only minor distress while drinking and racing at her limit on the run course - something that’s very common amongst elite triathletes and runners
- Rebecca also nailed her use of caffeine during this race, with an intake of ~594mg putting her just above the general recommendations of 3-6mg per kilo of bodyweight for performance enhancement. This ensured she maximised the chance of experiencing all of the benefits associated with caffeine
Conclusions
- Rebecca did well to overcome adversity and still crush her carb, fluid and electrolyte intake targets throughout the race
- Going forwards Rebecca is going to experiment with the timing of her carb and caffeine intake to optimise her perceived energy levels, especially when transitioning from bike to run
- Overall, this was an excellent early season race for Rebecca which should give her confidence for upcoming events. Additionally, finishing 3rd here means she secured her ticket to Kona for the World Championships later in 2023
Key info
Rebecca Clarke
Female
Sweat sodium concentration
563mg/L
Sweat sodium classification
Low
* determined by a PH Advanced Sweat Test
Result
Position
3rd
Overall Time
9:10:11
Swim Time
0:50:35
Bike Time
4:57:34
Run Time
3:16:38
Event information
Sport
Triathlon
Discipline
Full distance
Event
IRONMAN New Zealand
Location
Taupo, New Zealand
Date
4th March, 2023
Website
Swim Distance
3.9km / 2.4mi
Bike Distance
180.2km / 112.0mi
Run Distance
42.2km / 26.2mi
Total Distance
226.3km / 140.6mi
Race conditions
Weather Conditions
Hot and Humid
Precipitation
No Rain
Min Temp
16°C / 61°F
Max Temp
23°C / 73°F
Avg Temp
20°C / 68°F
Humidity
70%
Athlete feedback
Race Satisfaction
8/10
Hydration rating
6/10
I felt quite thirsty on the run
Energy levels
7/10
I felt pretty good throughout the bike, but felt I was lacking some energy at the start of the run
Toilet stops
No
This suprised me considering that I managed to go in Kona where it was far hotter!
GI comfort
7/10
I had a few periods of discomfort, all while on the run and relying more on aid stations
Cramping
Twinges but not full-on cramps
Rebecca's Thoughts
I'm happy to have been on the podium and bagged my slot for Kona, but being so close to the win makes small mistakes seem so much more impactful.
Rebecca's full stats
| Carbohydrate (g) | Sodium (mg) | Fluid (ml) | Caffeine (mg) | Relative sodium concentration (mg/L) | |
|---|---|---|---|---|---|
| Overall | |||||
| Total intake | 740 | 3,945 | 7,635 | 597 | 517 |
| Per hour | 81 | 430 | 833 | 65 | |
| Bike and Run | |||||
| Total intake | 710 | 3,945 | 7,635 | 597 | 517 |
| Per hour | 86 | 480 | 929 | 73 | |
| Bike | |||||
| Total intake | 516 | 3,432 | 5,375 | 366 | 639 |
| Per hour | 104 | 693 | 1,086 | 74 | |
| Run | |||||
| Total intake | 195 | 513 | 2,260 | 231 | 227 |
| Per hour | 60 | 157 | 692 | 71 | |
Data Confidence
1
2
3
4
5
There is some confidence in the quantities and brands of products consumed but the data may lack specifics (e.g. volumes, specific flavours). A high number of estimations have been made and the room for error is moderate-high. There may also be the possibility that some intake has been grossly over- or under-estimated.