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Tara Grosvenor's scorecard

Trail 100 Andorra by UTMB

Saturday 24th June, 2023

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 54g

    Carb per hour
  • 380mg

    Sodium per hour
  • 711ml

    Fluid per hour
  • 534mg/L

    Relative sodium concentration
  • 373mg

    Total caffeine
  • How Tara hit those numbers

    500ml x PH 1500 (Drink Mix)
    1 x Bowl of rice with syrup and cinnamon
    1 x Energy gel (25g carb)
    10L x PH 500 (Tablets)
    2 x PH Electrolyte Capsule
    3 x PF 30 Energy Gel
    3 x PF 30 Caffeine Gel
    3 x PF 30 Energy Chews
    1.5L x Plain water
    750ml x Coca Cola Original
    6 x Jelly Babies
    250ml x Chicken broth
    9 x Energy gel (25g carb)
    1 x White rice (cooked)
    1 x Bounty Chocolate Bar
    4 x Battenberg slices
    2 x Bubblegum Fizzy Laces
    3.5 x Rowntrees Berry Hearts
    2 x Rowntrees Randoms Juicers
    1 x Naak Stroop Waffle
    5 x Watermelon Pot
    330ml x Schweppes Fizzy Agrum
    330ml x Fanta Orange
    1L x Naak Watermelon Drink Mix

    How Tara's hydration and fueling went...

      • This 105km (65 mile) race saw former professional triathlete, Tara, push herself to new limits. She’d never previously run for longer than 10.5 hrs, further than 69km (42 miles), or climbed an ascent profile greater than 3,600m (11,800ft), or in a European mountain race! The Andorra 100 ticked all those boxes, and she completed her race in a strong 20 hours 41 minutes
      • Tara used aid stations along with her individualised fueling and hydration strategy to power her body through the race, learning as she went


      • Throughout the race, Tara took in an average of ~711ml (25oz) of fluid per hour, which is a high fluid intake to maintain over the long time frame of the ultra
      • She took on ~10L (320oz) of PH 500 throughout, in an attempt to replace the fluid and sodium losses she was experiencing through sweating over the course of a 20-hour race where temperatures averaged 27 ℃ (80.6℉)
      • Tara hit a high fluid intake throughout, but reported that she needed to pee a lot during. This may have been a result of her not replacing the sodium she lost effectively and we would suggest that Tara swaps out the PH 500 for some PH 1000 to increase her relative sodium concentration slightly
      • Tara took on a relative sodium concentration of ~534mg/L (mg/32oz), which is slightly lower than her sweat sodium concentration of 712mg/L (mg/32oz), which means she will have built up a decent deficit due to the long duration of the ultra


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Using an approach that’s fairly common for ultra runners, Tara went for a combination of ‘real’ foods alongside sports nutrition products, including PF 30 Gels and PF 30 Chews
      • Tara began her pre-race fueling the night before by eating a carb rich dinner of chicken, rice and pesto along with preloading her hydration with PH 1500
      • She began her pre-race fueling 30 minutes prior to the start with a 25g carb energy gel, whichincreased her glucose levels just before she began running and helped save her glycogen stores for the 105km ahead
      • She then continued her strategy using more 25g carb gels throughout the race along with incorporating some PF 30 Gels, PF 30 Caffeine Gels and PF 30 Chews throughout
      • Tara also used aid stations, picking up a variety of different sweets and other carb sources, such as a bowl of rice, some chicken broth and cups of Coca Cola
      • She felt that she could’ve spent longer at the aid stations in the middle of the day, getting herself out of race mentality and focusing on the fact that she needed to fuel for the hours ahead
      • Towards the end of the race, Tara fixed this, reporting that “having chicken broth sat in a deck chair at the penultimate aid station was the best thing I could ever have eaten” perhaps indicating her sodium levels were low, and her body was beginning to crave saltier foods towards the end of the event
      • Tara’s overall carb intake was ~54g per hour, which for a race of this duration is not too far off the recommended intake of ~60g/h. The fact Tara reported feeling positive about her fueling strategy would suggest that she did a good job of nailing her strategy for her debut ultramarathon


      • Tara felt she ate well throughout the race, enabling her to push through any tiredness
      • She may want to adapt her hydration strategy for future races to prevent needing to pee so frequently, balancing her fluid intake with her sodium replacements to more closely match her sweat sodium concentration

    Key info

    Tara Grosvenor

    Sweat sodium concentration
    Sweat sodium classification
    * determined by a PH Advanced Sweat Test


    Overall Time

    Event information

    Trail 100 Andorra by UTMB
    Ordino, Andorra
    24th June, 2023
    Total Distance
    105.0km / 65.2mi
    Total Elevation
    6,900m / 22,638ft

    Race conditions

    Weather Conditions
    Very Hot
    No Rain
    Min Temp
    18°C / 64°F
    Max Temp
    31°C / 88°F
    Avg Temp
    27°C / 81°F

    Athlete feedback

    Race Satisfaction
    Toilet stops
    GI comfort
    No cramping

    Tara's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake1,1107,85314,703373534
    Per hour5438071118

    Data Confidence







    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.

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