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Event Nutrition and Hydration Guidelines for Optimum Performance
By Peta Hood (Accredited Practising Dietitian, Accredited Sports Dietitian)
Lifestar Nutrition and Exercise Physiology www.lifestarnutrition.com.au
For Cam’s Cycle Coaching www.camscyclecoaching.com
Nutrition
Your nutrition and hydration strategy for this event will be of equal importance as your training. Meeting your
carbohydrate and hydration requirements on the day will help you remain focused, well-fuelled, well-hydrated,
and performing at your best. Adequate nutrition and hydration during the event, will also assist with optimising
your recovery after the event.
Carbohydrate (glucose) is essential for energy, and is the main fuel utlised by our bodies for exercise of
moderate to high intensity. We do utilise fat for fuel, however it is not readily available at high intensity. A
carbohydrate-rich diet (e.g rice, pasta, bread, fruit) leading up to the event, will help you store some
carbohydrate (in the form of glycogen within your muscles), however glycogen stores only provide sufficient
energy to last around 90 minutes at race pace. It is therefore essential to develop a pattern of eating and
drinking throughout the event, to help meet your energy demands.
What should I eat?
A combination of sports foods (such as gels, lollies, sports bars and sports drinks) + carbohydrate-rich real
foods (such as pikelets, mini muffins, muesli bars, fruit cake, cut sandwiches, and bananas) usually works
best to prevent flavor fatigue and gastrointestinal upset. Foods that are quick to consume will also be easier to
manage on climbs. Including some savoury options in the mix (such as vegemite, salt, or even a small amount
of cheese) can break up the monotony of a sweet palate and also provide valuable sodium to help replace
losses via sweat. Try to avoid relying too heavily on foods rich in fiber (e.g. dried fruit, whole grains or seeds),
or fat (e.g. nut bars, nut pastes, paleo balls), as these can cause gastrointestinal discomfort. These foods can
be included, but in small quantities and always pre-trialed.
When should I eat?
Aim to eat or drink every 30 minutes, starting early in the event, rather than waiting for hunger or thirst, or
even worse, fatigue, to set in.
How much do I need to eat?
Carbohydrate needs vary between individuals, depending upon factors such as exercise intensity and fitness
levels; however a good guide for most riders is to consume 40-60+ grams of carbohydrate per hour during
the event. This equates to 2-3 carbohydrate-containing foods or drinks per hour, and is best achieved through
the consumption of a variety of food and drink options, all trialed for tolerance and practicality before the
event. Most sports foods contain between 20-30 grams of carbohydrate per serve, and the carbohydrate
content of other foods can be determined from labels.
Hydration
The goal of hydration during exercise is to help replace fluids lost through sweat and metabolic processes.
Adequate fluid consumption helps to prevent dehydration, muscle cramping and fatigue, loss of concentration,
and heat illness. As little as two percent dehydration can negatively affect performance. Extreme dehydration
can lead to cardiac complications and even death so your hydration needs to be taken seriously!
What should I drink?
Water is the first point of call, and what our body relies on most. Sports drinks provide a convenient
combination of carbohydrate (5-8%), fluid, and electrolytes. Cordial, juice, and soft drink should be consumed
less frequently, as they can cause gastric upset and diarrhoea due to their higher carbohydrate content (812%).
Electrolytes such as sodium, potassium, calcium and magnesium play an important role in muscle
contraction, heart function and fluid balance. Electrolyte replacement is typically recommended during
exercise lasting greater than 1.5 hours, of very high intensity, or in the heat; in particular, replacement of
sodium to prevent hyponatraemia (low blood sodium), which can be extremely dangerous.
Electrolyte needs are highly individual, but some athletes require up to 500 mg of sodium per hour during
extended exercise. Sports drinks (~280 mg sodium) may not adequately replace electrolyte losses in these
conditions, meaning more concentrated and electrolyte supplements such as Endura, Nuun or Shotz may be
needed. Sodium can also be replaced by eating high-sodium foods. Magnesium may assist in the
management of cramps for a select few individuals, but again this must be trialed and tested before the event.
How much should I drink?
Sweat rates and fluid needs are highly individual (due to genetics, body composition, and fitness level)
and are also influenced by environmental factors (heat, wind and humidity), and clothing choice (degree of
skin exposure). 500-1000 mL of fluid per hour (~1 bidon per hour) is a very rough guide; however knowing
your individual sweat rate gives you a much better indication of how much you should be drinking during
exercise.
You can follow these easy steps to estimate your sweat rate during a training ride:
{NB. 1 Litre of fluid = approximately 1 kg in weight}
1. Weigh yourself naked before training. Ideally you should empty your bladder before weighing. E.g.
Starting weight = 71 kg.
2. Commence your ride. Keep track of time of your ride time e.g. 3.25 hrs.
3. Keep track of any fluid or food consumed during the ride e.g. 2 x 600 mL bidons (1200 g) + 1 x
Powerbar (65 g) = 1200 g + 65 g = 1265 g.
4. Estimate any urine output e.g. 150 mL.
5. Weigh yourself naked after the ride; towel yourself down to remove sweat.
6. Pre-exercise Weight
Total weight of fluid and food consumed during ride
Estimated urine output
Post-exercise Weight
FLUID DEFICIT = (71kg + 1.265 kg – 0.150 L) – 69 kg
= 71 kg
= 1.265 kg
= 0.150 L
= 69 kg
= 3.115 kg or 3.115 Litres
ESTIMATED SWEAT RATE = FLUID DEFICIT  TIME
3.115 L  3.25 hrs ride time > 0.958 Litres (958 mL) / hour
It is not essential to replace 100% of fluid losses each hour; in fact this can be detrimental. Over-hydrating can
be harmful. However, knowing your sweat rate gives you a good guide as to what to work towards. Most
athletes replace anywhere from 70-80% of their sweat losses.
An Accredited Sports Dietitian can help you formulate an individualised hydration (and nutrition) plan to
optimize your performance. A sensible investment!
Eat smart, ride hard. All the very best for the event!
Peta Hood (APD)
BHthSci (Nut&Dt)/BAppSci (HMS) (Hons)