Whether you are in Adelaide, Melbourne, Sydney or Falls Creek this week, it doesn't matter, it's going to be hard to escape the heat. Team Tempo Athlete and Sports Nutritionist Liv Warnes has been kind enough to share some important tips on Hydration to help all runners cope with the heat, and help you to maintain your training quality throughout the summer. Liv has been a crucial member of the team that works with Jess Trengove, and supported her with some of the tips below to achieve her 11th placing (Marathon) in high temperatures at the Moscow World Championships in 2013.
It is well established in the literature as little as 1.5 - 2% change in body weight from fluid loss and an elevation in core body temperature can reduce both physical and mental performance. Strength and power are both reduced by 2 and 3% respectively, as dehydration levels approach 3-4%.
PRE-COOLING FOR PERFORMANCE
A rise in core body temperature is the critical factor in reduced performance and the onset of fatigue when exercising in the heat. Pre-cooling has been shown to be an effective method for lowering pre-exercise core temperature, increasing heat storage capacity and improving exercise performance. The benefits of pre-cooling also include reductions in cardiovascular and psychological strain that all contribute to improved performance.
Factors Impacting on Hydration Status:
There are numerous factors impacting ones hydration status. These include;
* Environmental conditions
* Intensity of exercise session
* Duration of session
* Clothing worn
* Individual physiological characteristics i.e. sweat rate is impacted by training status. The fitter you get, the greater your sweat rate.
A 'one size fits all' approach to maintaining optimal hydration status is not effective. Therefore consider trialing some of the strategies below in training, to develop a hydration plan to enhance your running performance in the heat.
HYDRATION STRATEGIES IN THE HEAT
* Start sipping on water early in the day, and be consistent with your intake throughout.
* Include a fluid option with each meal.
* Add salt to meals.
* Aim to consume 1L cold fluid (at 4or less) approximately 1 hour prior to training. This may be a little too much for some prior to high intensity sessions.
* Pre cool with any (or all) of the following prior to a training session or race; icy fluid-slushie consumption, 5 minute ice bath, ice cold wet towels on head, arms, neck, legs.
* Weigh yourself pre and ASAP post session/race (same clothing)- replace 150% sweat loss i.e. 1kg = 1.5L.
* Use Sports Drink or add Gastrolyte/Hydralyte to water and practice consuming during the session. Use post session if your fluid deficit is large (i.e. >1.5kg).
N.B. You can train your body to tolerate greater fluid consumption during exercise. For those of you racing longer distances, this is important to practice in training.
Sports Dietitian, APD
* For an appointment call Sportsmed SA, Stepney on 8362 8111. *