How Does Dehydration Impact Performance?

Imagine This...You have just passed the 15km mark, it’s 29°C and the sun is blazing. You start to sweat as the temperature heats up…

What Happens Next?

To avoid an extreme rise in your core temperature, your body has several physiological mechanisms it uses to cool you down. During exercise the primary means of cooling you down is evaporative heat loss, or in other words, sweating. High intensity exercise in warm climates can result in sweat losses of up to 1.0 - 2.5 L per hour and unless the amount of sweat you lose is matched by your fluid intake, you could become dehydrated.

The Heat Is On

In the heat of summer when the environmental temperature is higher than that of your skin, your core body temperature rises rapidly. Your body’s cooling response in these circumstances is to secrete more sweat for evaporation, however, when the amount of sweat you are producing exceeds the environment’s capacity to evaporate it (i.e. on hot, humid days), the result is a greater loss of water and electrolytes without any cooling effect. To stop you over-heating on hot, humid days, therefore, your body needs to increase the amount of heat lost through your skin. Your body does this by increasing blood flow to your skin, which increases the transfer of heat from your core to your skin. This is why your skin can become red and flushed when you are exercising in the heat. It’s all designed to help cool you down when the heat is on!

Dehydration and Your Performance

Sweating is obviously a very important part of helping cool you down in the summer heat, but you don’t want to lose too much fluid as even a small amount of fluid loss can have a big impact on your performance. Insufficient hydration during exercise reduces your blood volume and makes it difficult for you to regulate your body temperature as you don’t have the capacity to increase blood flow to the skin. This causes elevated heart rate, significantly reduces performance potential and makes exercise seem more difficult. Coupled with heat, dehydration increases your risk of developing muscle cramps, heat exhaustion and heat stroke.

Water or Endura Rehydration Formula?

Water alone is not the best way to replenish fluid lost during exercise as it can increase urine output and reduce your desire to drink. During prolonged exercise, a rehydration formula containing both carbohydrates and electrolytes should be used to maintain performance and stamina, and to optimise water absorption and retention. Endura Rehydration Formula contains magnesium and electrolytes in ratios similar to those found in muscle cells, which are delivered through an activated mineral co-transport system for greater bioavailability.

Endura Rehydration Formula also contains specialised carbohydrates which aid in replenishing glycogen stores to prevent the breakdown of important muscle tissue during intense exercise. These carbohydrates are in the form of glucose polymers and micro-crystalline fructose to enhance gastric emptying for more rapid fluid absorption and temperature control, which is especially important when you are exercising at high temperatures.

Hot Tips for Preventing Dehydration

Staying hydrated is crucial when you are exercising at high temperatures as it promotes an optimal physiological response to ensure you stay cool – even in the hot summer months. To beat the heat this summer, just follow these simple tips:

  • Commence exercise fully hydrated by consuming 400 – 600 mL of fluid two hours prior to exercise. Pre-exercise hydration improves peak performance capacity, increases time to fatigue, and delays the onset of dehydration.
  • During prolonged exercise, consume at least 150 – 300 mL of an isotonic hydration formula (2 scoops of Endura Rehydration Formula in 700 mL water bottle) every 15 - 20 minutes. The diluted formula provides an optimal concentration for fluid absorption.
  • To aid post-exercise muscle recovery and to replenish lost fluids take at least 1 serve of Endura Rehydration Formula and aim to consume enough fluid post-exercise to replace sweat lost. The amount that you need to consume will depend entirely on how much you sweat during the event.
  • Have plenty of Endura Rehydration Formula on hand during training and events and ensure adequate breaks to rehydrate.
  • Familiarise yourself with the signs of heat stress and have an action plan in case of heat illness, but most importantly aim to exercise at a cooler time of day.
  • If you are feeling the heat in a training session it's not worth causing a potential illness. If you fell unwell, stop the session, slow down or walk for a while until you recover. Listen to your body, it knows best.