Vox Performance Project blog: Holly Seear


At the beginning of August as the UK had an unprecedented heatwave, where we saw temperatures of 32-38 degrees each day, I completed my final big 4 day block of training pre Badlands.

Saturday and Sunday I did an off road MTB adventure of 330km / 4600m+ completing the Dorset 330 before riding on the Monday and Tuesday to/from the Precision Fuel and Hydration office in Christchurch (165km / 1500m+ each way) for a very appropriately timed Sweat Test.



I had raced at Gritfest with the Precision Fuel and Hydration team in June and discussed with Andy about visiting the office for a sweat test to see if I really was losing as much salt I suspected. 

After riding via the gorgeous New Forest I was not sure I had any sweat left to test, but James attached me to some electrodes to induce sweating on a patch of my arm. The sweat was then collected (and turned worryingly blue) before being put in the test box to be analysed. It was completely painless and only took about 15 minutes. You can see a video of the process here

I had a long discussion with James, while we waited for the results, about my training and upcoming race and how to work out what I might need to do to stay hydrated in the desert at Badlands where temperatures are often well over 40 degrees by the afternoon. Badlands is an off road, unsupported, ultra-race where the clock never stops, and the route covers several mountain ranges and two deserts.

The results showed I lose 1371 mg of sodium per litre of sweat and I received a report with suggested hydration plans for pre-hydrating, training and racing. With a high sweat rate and high sodium loss these plans would be vital. You can see from the photos the amount of salt I lost in the race. 




With remote stretches of desert and extreme temperatures I used a 3L Apidura frame bladder as well as additional collapsible bottles. Where possible I found real food, coffee and fizzy drinks but carried and used:

 4 x PH1500 sachets per day

Mega gels containing 90g of carb which are resealable and great for when food supply was short or the body was struggling to digest food, they have a natural taste and are easy to swallow on the move. 

Caffeine gels with 30g carb with 100mg caffeine for alertness at night

The total distance covered was 783km and 15,835m of elevation and we finished 10th pair after 89hrs and 25 minutes of hot racing. 


Until next time,


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