Your hydration balance depends on how much you sweat, your diet, elevation and even humidity. A healthy diet delivers about 20 per cent of fluid intake, says Kim Schwabenbauer, a USA Triathlon coach. Turn to watermelon, grapefruit, cucumber, broccoli, apples and grapes as snacks to increase your fluid consumption. Or naturally flavour your water with berries, lemon, kiwi, pineapples or oranges. Studies show that if your fluids are flavoured, you’ll drink more.
Even minor dehydration can affect physical and cognitive performance, as well as overall health. Imagine your cells are happily swimming around in a pool, awash in an abundance of fluid. Dehydration reduces the amount of fluid circulating in your bloodstream. This makes your heart work harder, limits your body’s ability to cool itself and prematurely fatigues your muscles. Your blood becomes more viscous – thicker, stickier, more concentrated. So don’t shrug off hydration. Pay attention.
Sodium isn’t evil. You need the nutrient to survive, and your body can’t produce it on its own. The electrolyte (yes, that’s what sodium is) contributes to blood volume, and, if you’re active, that’s a biggie. Maintaining normal blood volume helps your skin dissipate heat, helps you absorb nutrients and delivers oxygen to hardworking muscles, including your heart. Sodium is the mineral lost in the greatest quantities in sweat and urine, and replacing it is essential for proper hydration. So how much is too much? It’s complicated. Check out the chart on the next page for more details.
True, but there’s nothing magical about bananas. The potassium in bananas may be key. Potassium, another electrolyte, helps blunt the effects of sodium and, with help from your kidneys, moves it out of your body. Think of sodium and potassium on opposite sides of a seesaw, working to balance each other to achieve proper hydration. Most people get around half the recommended 4,700 milligrams of potassium daily, says Megan Meyer, of the International Food Information Council Foundation. Imbalance can also affect blood pressure and heart contractions.
That’s like saying everyone needs to eat 11,700 kilojoules a day. (They don’t.) Depending on body weight, activity level and temperature, your daily fluid needs can range from as little as 1.8 litres to more than 5.6 litres per day. On days when you don’t exercise, assess your pee. Your urine should look more like lemonade than water or apple juice. Dark urine often reflects dehydration. On days when you work out, weigh yourself pre- and post-exercise. For every half-kilogram of weight you lost, you’ll need to drink 2½ to 3 cups of fluid to restore balance.
FOOD STYLING: JAMIE KIMM; PROP STYLING: ANGELA CAMPOS/BERNSTEIN & ANDRIULLI ■