< Back to case studies

Anna-Marie Watson's scorecard

Mozart 100

Saturday 18th June, 2022

Within recommended ranges

Just outside recommended ranges

Significantly outside recommended ranges

  • 30g

    Carb per hour
  • 463mg

    Sodium per hour
  • 648ml

    Fluid per hour
  • 714mg/L

    Relative sodium concentration
  • 0mg/kg

    Caffeine per bodyweight
  • How Anna-Marie hit those numbers

    1 x Bowl of muesli with chocolate milk
    1 x Banana
    250ml x Plain water
    4.5L x PH 1500 (Tablets)
    7 x PF 30 Chews
    5.16L x Plain water
    2 x Banana
    1 x Peanuts (roasted, salted)
    1 x Energy bar (40g carb)
    1 x Energy bar (40g carb)
    1 x Energy bar (37g carb)
    1 x Watermelon Chunks
    2 x Orange
    2 x Tomato
    0.5 x Avocado

    How Anna-Marie's hydration and fueling went...

      • Jumping straight back in the deep end, ultra-runner Anna-Marie Watson, pushed through hot conditions at Mozart 100 in Austria, in what was her first race abroad since COVID-19 started
      • Having not raced an event this long since 2019, the PF&H ambassador and performance coach battled the blisteringly hot conditions which reached 31℃/88°F at some points during the day
      • Despite it being, in Anna-Marie’s words, a “sufferfest” with many athletes dropping out due to the heat and staggering 5,000m of elevation, Anna-Marie hydrated and fueled sufficiently throughout to finish the 100 km race in a time of 15 hours 28 minutes


      • Anna-Marie should consider preloading ~90 minutes before the start by drinking PH 1500 instead of just plain water to make sure she starts optimally hydrated
      • Throughout the race, Anna-Marie’s hydration strategy primarily involved using two 500ml/16oz soft flasks, one with PH 1500 and the other filled with plain water, which she refilled at all aid stations except the first and last (11 aid stations in total). To get more fluid in, she also drank ~100ml/3oz of water when she stopped to refill at stations 4 to 9
      • In total she drank ~10L/338oz fluid, which averages as ~648ml/22oz per hour. This was unsurprisingly higher than what we saw her drink during the much shorter and cooler race in Devon (~421ml/14oz per hour) back in February
      • Although we don’t have data on Anna-Marie’s sweat rate, drinking over ~600ml/h (20oz/h) is on the surface a decent volume over a race of this long duration. Anna-Marie agreed, saying “my hydration went well” and she mentioned that she peed three times during the race, which would indicate she didn’t under hydrate
      • In terms of sodium, she consumed an average of ~463mg/h, predominantly from her flasks of PH 1500. In relation to the fluid and additional plain water she took on board, the relative sodium concentration of her intake was ~714mg/L. This is a lower relative sodium concentration than what we saw her consume in Devon, and from our Sweat Test we know she is a ‘salty’ sweater (losing ~1,187mg/L). Therefore Anna-Marie may have benefitted by taking on slightly more to replace a greater proportion of her sodium losses in the heat, for example by using some Electrolyte Capsules for an easy, convenient way of getting a little extra sodium in
      • But, Anna-Marie positively reported no hydration-related issues, including no cramps, and mixed plain water into her strategy as she felt she needed. Ultimately, this allowed her to perform and push on in the heat, unlike many other competitors who DNF’d


    Quick Carb Calculator Recommendation


    carb 30 mins before


    carb per hour during
      • Ahead of the early race start of 5.00am, Anna-Marie ate a carb-rich breakfast consisting of a bowl of muesli with chocolate milk and a banana to top up her much-needed glycogen stores
      • She could also consider taking a final carb dose (~30g) in the last 15 minutes to spike her blood glucose and spare muscle glycogen. As Anna-Marie prefers not to use gels, she could look to take a banana, flapjack or energy bar in this time window if she feels this would be beneficial
      • During the run, Anna-Marie took on PF 30 Chews, energy bars and bananas as her main fuel source; in addition to this she picked up a wide spectrum of fruits available on course which included watermelon chunks, oranges, tomatoes and half an avocado
      • Using this strategy, Anna-Marie consumed an average of ~30g of carbohydrate per hour. During a race of this duration, this hits the lower end of the general recommended range (30-60g/h), and our Fuel & Hydration Planner would advise her to push towards 60g/h as there is a correlation between higher carb intake and performance
      • Anna-Marie reached a similar level of carb consumption to what we saw from her at the South Devon Marathon, 33g/h, over the shorter race.
      • At the 77km mark, she did however report “feeling sick” and that she “couldn’t eat anymore”, but puts this mostly down to the extreme temperature and physical stress on her body at this point in the race. Nonetheless, when looking to increase her intake going forward, we would recommend she undergoes extensive ‘gut training’ to be able to happily tolerate a higher carb intake
      • Due to this stomach discomfort creeping in just under the halfway mark of the race, her energy levels did dip and she said she “would have loved to have had more solid food”. After this point, her main focus was on completing the race and less on performance, so she took on what she felt she needed to get to the finish line
      • In terms of caffeine, we have learnt that Anna-Marie has a low tolerance towards it as it can make her feel jittery, therefore she makes the smart choice to cut it out of her race day fueling plan


      • Despite this ultra event being a lot more physically demanding and longer in duration than her Devon marathon, Anna-Marie again followed a simple and effective hydration plan to “hang on in there” despite feeling as if she wouldn’t be able to finish in the tough conditions at some points
      • In future events in hot conditions, Anna-Marie may benefit from preloading and taking on board slightly more sodium to keep on top of her losses. Trialing some gut training may also help her body tolerate a greater carb intake over longer races and push towards the 60g/h mark without gastrointestinal issues
      • With Anna-Marie having TDS coming up in late August, we look forward to seeing how she prepares for this event and adjusts her hydration and fueling to the demanding race

    Key info

    Anna-Marie Watson

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


    Overall Time

    Event information

    Mozart 100
    Salzburg, Austria
    18th June, 2022
    Total Distance
    100.0km / 62.1mi
    Total Elevation
    5,000m / 16,404ft

    Race conditions

    Weather Conditions
    No Rain
    Min Temp
    13°C / 55°F
    Max Temp
    31°C / 88°F
    Avg Temp
    24°C / 75°F

    Athlete feedback

    Hydration rating
    My hydration went well but I think I could improve my nutrition
    Toilet stops
    Three times, which is normal for me
    No cramping

    Anna-Marie's full stats

     Carbohydrate (g)Sodium (mg)Fluid (ml)Caffeine (mg)Relative sodium concentration (mg/L)
    Total intake4597,15610,0180714
    Per hour304636480

    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.

    Anna-Marie's recent case studies

    see all

    Related case studies

    Nail your next event with a FREE Fuel & Hydration Plan
    Get started