Myth #3: Drink as much water as possible before a race.
Drinking too much water can lead to more than just frequent trips to
the bathroom. Hyponatremia, a dangerous drop in blood-sodium levels
that can be life-threatening, results from overdrinking—replacing
water without adequately replacing sodium lost through sweat.
Dizziness, confusion, swollen hands and feet, a throbbing headache and
a bloated stomach during or following prolonged exercise can signal
overhydration and a dilution of blood-sodium levels. Rapid weight gain
during exercise is a definite warning sign that you're overdrinking.
More: How to Avoid Dehydration on Race Day
Female runners are at greater risk due to a smaller blood volume and an
increased likelihood of being hyper-vigilant about hydration,
especially if following a low-sodium diet. Heavy sweaters, beginning
marathoners who tend to run slowly (therefore with more opportunities
to drink) and endurance junkies running for more than four hours need
to be especially careful about this condition.
To protect yourself from the hazards of both over and underdrinking,
follow the International Marathon Medical Directors Association (IMMDA)
evidence-based simple rule: Drink when thirsty. In other words, drink
to stay hydrated--don't overdrink. Consume sports drinks (with at least
110 milligrams of sodium in eight ounces) for runs longer than an hour
or when appropriate to avoid low sodium levels.
More: How Much Water Should You Drink?
Myth #4: Female runners don't need sports drinks.
Female runners often shortchange themselves by skipping sports drinks
or using them incorrectly. If you run longer than 60 minutes at a
moderate pace, you need to drink every 15 to 20 minutes after the
one-hour mark. Based on 30-plus years of scientific research, experts
continue to recommend sports drinks that supply fluid, carbohydrate and
electrolytes over water during longer training efforts and races.
More: Which Fluid Hydrates Beset: Water or Sports Drink?
A well-designed sports drink should contain sugar (carbohydrate) and an
ample amount of sodium. Carbs, stored as glycogen, are your body's
preferred fuel during exercise, and are the only fuel it can burn
during intense or anaerobic efforts, such as sprinting for the finish
line.
Your body's glycogen stores are limited, however, so
supplementing with a sports drink when you plan to race all-out or push
yourself longer than 60 minutes is a real performance booster. Salt is
added to improve the absorption of carbs and to help replace the sodium
lost through sweat.
Experiment with different sports drink brands to find one that works
for you before race day. (Your stomach might not tolerate them all.) If
you choose not to consume a sports drink, you still require sodium and
supplemental carbohydrate. Carry energy gels (take with water to
dilute), and try various electrolyte products such as Nuun tablets to
keep up with your sodium needs.
More: How to Create a Race-Day Hydration Plan

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