09 steps to fuelling up
A variety of proven ways to stay hydrated and strong this summer
01 Find the sodium balance
After 20mins of scientific wizardry, it transpires that I’m a salty sweater. “You lose 1,290mg of sodium per litre of sweat,” states Andy. “Very low is 200-300mg/l; very high is 2,000mg/l. The average is 970mg/l.” The numbers show the range of sodium loss in athletes and explain the white sweat marks on my jersey. The result means I should use Precision’s higher PH1000 and PH1500 electrolyte tabs. But why is sodium loss important?
Sodium helps to maintain blood plasma volume and transport water from the bloodstream to working muscles. If a rider’s drink contains liquid with little sodium, the body won’t retain it. Sweat contains salt, comprising 40% sodium/60% chloride, so the more you sweat, the more sodium you lose. But sodium losses are just one part of the hydration jigsaw, says Blow.
“The sweat score on its own isn’t an indicator of what a rider should be drinking. What you should be drinking will depend on how much you’re sweating, what you’re sweating, and over what time period.”
02 Hydrate, but don’t overdrink
Hyponatremia is a condition when the concentration of sodium in your blood is abnormally and dangerously low, and can lead to athletes collapsing or worse during endurance sports events. “Hyponatremia can be a result of athletes shifting from slightly under-drinking before training to significantly over-drinking pretraining with plain water or weak sports drinks, which leads to an inadequate replacing of the sodium lost when sweating and further dilutes the concentration of sodium in the body,” Andy continues.
So how do we find the balance between preloading and overdrinking? “Take in one or two additional cups of fluid each day in the final couple of days before your event but don’t go crazy by drinking above what your body is telling you it needs. Urine colour and thirst are helpful indicators of hydration status disposal. Ensure your pee isn’t too dark in colour or low in volume and don’t mistake a large amount of really clear urine as a universally good thing. You can increase sodium intake by adding electrolyte supplements to the water that you’re drinking or by putting additional salt on your food.”
03 Train your gut
It’s not just fluids that I’m advised on. Carb consumption and replenishing my stores of glycogen are also essential, with PH suggesting that I’ll need to consume around 60g of carbs per hour (i.e. two of PH’s 30g gels) during my next big event, the 275km Viking Gran Fondo.
“To do this, you’ll need to increase your carb consumption in training from 20 to 30, 40, 50 and then 60g per hour to prepare your gut for
event day,” resident sports scientist Abby Coleman tells me. “Do this for the 4-5 weeks it takes to get to the top end of your target and drip feed the carbs over the hour. The key is a gradual approach to allow your gut to adapt.” Head overleaf for more.
05 Acclimatise on the turbo
Heat acclimatisation is useful if your event is somewhere hot, as it teaches your body to sweat, and you can also do this at lower intensities indoors. When you’re on the turbo trainer, turn off the fan and/or shut any windows and you’ll gradually improve. You can also move the turbo somewhere hot like a conservatory, which is something triathlete and famed heat sufferer Jonny Brownlee did before the 2020 Olympics in a bid to replicate the heat of Tokyo in the Yorkshire winter (the result was a gold medal in the relay and a top five finish in the individual event). Heat turbo sets are also an ideal time to practise your hydration strategy. And, if you don’t have a turbo or want to keep riding outdoors for all the benefits it brings, you can look at wearing more layers on your training rides ahead of your event.
06 Intensity matters
The intensity of riding is also key to your fuelling requirements, with my Danish ultra set to be largely (and hopefully!) conducted at a moderate pace. “A further point is to respect the relationship between intensity and glycogen usage,” adds Coleman. “Does your car use the same amount of fuel to go 50km/h as it does 100km/h? No, so keep in mind the intensity that you’re performing on your training rides and how they match up with the amount of fuel that your own tank needs. If you’re cycling at 150 watts and expecting to race at 250 watts, for example, you can’t expect your body to be able to process the same amount of fuel for each output.”
07 Have a hot bath!
In 2020, Dr Jessica Mee conducted research on pre-event acclimatising. The results found that if you take a hot bath after exercising in cool conditions, building up from 10 to 20 to 40 minutes (in the bath) over the course of six days, you get a profound reduction in resting core temperature of about a third of a degree, which more than bettered exercise heat acclimatisation.
08 Food for thought
Hot weather can also upset your digestion by reducing blood flow to the gastrointestinal tract. “Dehydration can also impair our ability to transport nutrients through the intestine lining,” says EF Pro Cycling nutritionist Will Girling. “Heat will lower your appetite so opt for liquids and semi-solids, such as energy gels.” For longer rides, try making homemade flapjacks as they have a higher moisture content than many dry energy bars.”