Hydration 101

With temperatures rising and summer just around the corner, its important to ensure that your body remains hydrated. With so much information out there on what, when and how much you should be drinking, it can often feel a little overwhelming. But never fear, todays blog will reveal all and help you on your way to achieving optimal hydration.

Why is fluid so important for our body?

 Good question - fluid is required for a number of essential processes in our body:

  • Regulating body temperature
  • Maintaining blood volume,
  • Transporting nutrients,
  • Lubricating and cushioning joints,
  • Aiding in digestion
  • Allowing muscle contractions to take place – just to name a few!

 Did you know: the human body can last weeks without food, but only a few days without water?

 Fluid is particularly important during exercise, as the body maintains an optimal temperature by sweating. If not adequately hydrated, the loss of body fluid from sweating can result in dehydration. Evidence has found that as the rate of dehydration is increased, physical and mental performance is gradually reduced.

 Our body is generally able to tolerate low to moderate levels of dehydration, however once these levels increase further (loss of fluid ³2% of body weight), our performance is impaired.

 How?

  • Increase in heart rate,
  • Raised body temperature,
  • Fatigue,
  • Perception of how difficult the activity feels,
  • Impaired cognition,
  • Gastrointestinal symptoms such as nausea, vomiting and diarrhoea.

How much fluid should we be drinking?

 Now this is the tricky part. Fluid requirements differ according to a number of factors, including the individual, the type of activity that is being performed and the environment that the activity is being performed in. Unfortunately, there is no “one size fits all” when it comes to fluid requirements, so it’s important to work closely with your Accredited Sports Dietitian to develop your own personalised fluid plan.

 Here at Body Fusion, we offer hydration testing for both individuals and sporting teams, which allows us to determine an accurate calculation of your body fluid loss and sweat rate. We are then able to use this information to develop your individual fluid plan to help you achieve optimal performance.

 When should we be drinking fluid?

 Again, this is very individualised and should be incorporated with your fluid plan. However, as a general rule: 

·      Be well hydrated when you begin exercise :Now, this doesn’t mean guzzling 5L of water just before your event. Do this, and you might find yourself frequently ducking off to the bathroom to urinate or experiencing bloating and gastrointestinal upset. You can check your hydration status before exercise by using a dehydration colour chart –pale-yellow straw coloured urine is a sign of adequate hydration. 

·      Ensure that you rehydrate after you finish: Your body continues to lose fluid even after you finish exercise, so it’s important to replenish 125-150% of fluid that was lost during exercise over the following 4-6 hours after finishing exercise.

What type of fluid should we be drinking?

 There are a LOT of different options on the market these days, so it can be tricky to find the best fluid option for you. Again, (I’m sure you’re sick of hearing me say this..) this is tailored to you as an individual and the exercise that you are performing.

·      Plain water

Usually the best choice! If you are exercising for less than 90 mins (short duration) or are performing a low intensity sport (no noticeable increase in breathing rate or sweat), water is best.  

·      Sports drinks

If the activity you are performing is high intensity (i.e. it requires a large amount of effort and causes rapid breathing, sweating and increased heart rate), or is an endurance sport (lasting >90 minutes) OR you sweat excessively, you may benefit from a sports drink containing carbohydrates and electrolytes. The majority of sports drinks are isotonic (meaning that the solution contains a similar concentration of salt and sugar as our blood and cells) and are rapidly absorbed in the body. These drinks contain 10-25mmol/L sodium, which improves fluid intake by stimulating our thirst mechanism causing us to drink more, along with reducing the volume of urine produced post-exercise and promoting carbohydrate and water uptake in the intestines!

·      Milk

 Recent studies have found that milk and other high-fluid dairy products such as yoghurt and custard are equally effective (or even better in some cases) as sports drinks! Along with water and electrolytes, milk also offers additional nutrients such as calcium to support strong, healthy bones. This would also be a fantastic post-workout snack to help your body refuel and repair!

·      Caffeine

 Small to moderate amounts of caffeine have been found to sustain exercise performance and reduce the perception of effort. Although caffeine is no longer banned by the World Anti Doping Agency, it would be advised that you discuss the use of caffeine with your Accredited Sports Dietitian prior to consider your individual response.

·      Alcohol

 Alcohol is not a suitable choice, as it can compromise rehydration and refuelling post-exercise and can worsen the extent of damage to muscle tissues. So make sure you reach for the right option before you start celebrating!

 

Tips for optimal hydration!

·      Ensure that you are adequately hydrated prior to exercise. There is less chance of becoming dehydrated if you are adequately hydrated to start with!

·      Always aim for a pale-yellow straw coloured urine. This usually indicates that you are sufficiently hydrated.

·      Don’t rely on thirst to prompt you to rehydrate. By the time that you become thirsty, there has usually been a significant loss of fluid. Your thirst will also be satisfied before your body has adequately rehydrated.

·      Develop a personalised fluid plan. Work with your Accredited Sports Dietitian to develop an individualised fluid plan tailored to your requirements.  

·      Make rehydrating enjoyable! Incorporate variety when rehydrating to make it more enjoyable, therefore you’re more likely to rehydrate sufficiently from drinking a greater volume. Dairy is a great option due to its variety in flavour, texture and taste.

 

Interested in hydration testing? Call the clinic today on 0426 500 251 (Ash) or 0410 533 213 (Kat).

References:

·      Sports Dietitians Australia

o  https://www.sportsdietitians.com.au/factsheets/fuelling-recovery/fluids-in-sport/

o  https://www.sportsdietitians.com.au/factsheets/fuelling-recovery/sports-drinks/  

·      Australia Institute of Sport

o  http://www.ausport.gov.au/ais/nutrition/factsheets/hydration/fluid_-_who_needs_it  

·      Maughan, R. J., Watson, P., Cordery, P. A., Walsh, N. P., Oliver, S. J., Dolci, A., . . . Galloway, S. D. (2016). A randomized trial to assess the potential of different beverages to affect hydration status: development of a beverage hydration index. The American journal of clinical nutrition, 103(3), 717-723.

·      Shirreffs, S. M., Watson, P., & Maughan, R. J. (2007). Milk as an effective post-exercise rehydration drink. British Journal of Nutrition, 98(1), 173-180. doi:10.1017/S0007114507695543

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Katrina Mills

Katrina is an enthusiastic and driven dietitian with a client-centered approach to nutrition and health. She understands the positive effects nutrition has on the ability to assist in recovery, ease symptoms and improve overall quality of life.