Hydration tips

As warmer weather and the road racing season begins, I am frequently asked about dehydration and the best hydration strategies for runners.

How important is proper hydration for runners? Dehydration as little as 2% of body weight can begin to significantly impact performance. For an athlete that has a higher sweat rate (greater than 2 liter per hour), that level of dehydration can occur after 30 minutes of exercise in hot and humid conditions. Additional, research has shown that level of dehydration can slow 10-km run times by 6.3% compared to running in a hydrated state. That equates to a race time almost 3 minutes slower if you usually run a 40-minute 10k!

Tips

Calculate your fluid losses – An easy way to determine sweat rate and fluid losses is to weigh yourself before and after a run, but before rehydrating. A one-pound weight loss is roughly equal to 500 ml (about 1 pint) of fluid loss. Remember to account for any fluids you drank during the workout.

Match your fluid losses – Overhydration can be as problematic as dehydration. If you overhydrate, you run the risk of hyponatremia. Since there is a wide variety in the rate of fluid loss among individual runners, the current American College of Sports Medicine guidelines don’t recommend a specific volume of fluid to drink per hour. A better guide to fluid replacement is to drink when thirsty and attempt to at least partially replace fluid loss during exercise.

Pre-hydrate – Starting a race or a training run already slightly dehydrated can have an impact on performance. Make sure you start a workout or a race well hydrated and start hydrating at least 60 minutes before exercise if possible. Smaller amounts of fluids (200 to 500 ml) are more easily and quickly absorbed -For longer races such as marathons, there may be a slight risk of developing mild hyponatremia (low blood sodium) before the race. Liquids containing electrolytes may decrease this risk compared to hydrating with only with water.

Drink during the run – Get in the habit of drinking during longer runs. Try running with a water bottle or run a course that has water or other fluids available. If you don’t like running with a water bottle, try a shorter loop course and leave the fluids at the start. Take a short break each time you pass the starting point.

Set the timer on your watch for every 15 or 20 minutes to remind yourself to drink. Try a sports drink for runs lasting longer than 60 minutes to help replace sodium and carbohydrates.

Post Work-out – Rehydration after exercise is also important for recovery. The best strategies include drinking smaller amounts of fluid over a period of time instead of drinking a large amount quickly once you finish the run. Sports drinks with electrolytes including sodium may help you to rehydrate quicker compared to water. A post-race meal higher in sodium will also help stimulate the urge to drink and replace lost fluids.

John M. Martinez, M.D. is Medical Director of Coastal Sports & Wellness Medical Center in San Diego, a comprehensive sports medicine clinic focusing upon active patients and athletes. Find out more at www.coastalsportsmedicine.com

This article originally appearred as part of the May Running Centers email newsletter. To learn more about the Running Centers or to find a location in Southern California, click here.

Ten Workout Tips

10 Tips for Safe Workouts

1. Get a check-up by your doctor
If you’re new to exercise and a male over the age of 40 or woman over the age of 50 or have a personal or family history of heart disease such as high blood pressure or heart attacks, get a check-up by your doctor before starting an exercise program. Other risk factors that may require a medical evaluation before starting an exercise program include:
- Current smoker
- Chest pain or tightness or shortness of breath with exertion
- History of asthma, diabetes or other heart, lung or kidney problems

2. Have a plan and a goal
Write down your fitness goals for the upcoming month, season and year, and then keep track of your workouts in a workout log. Review and update your goals monthly.

3. Make exercise a priority
You can’t success at your fitness goals if you don’t make it a priority. Try to schedule workouts earlier in the day. If exercise is on the top of your daily “To Do” list you’ll find it easier to commit to a daily routine.

4. The best place to start is where you are now…
Look at your current activities and see what types of exercise you may already be doing: walking the dog, playing with the kids, working in the yard are all forms of exercise.

5. Start gradually, increase gradually
Look at exercise as a lifestyle choice and make it a part of every day. Use these activities as a starting point and try to increase the amount of time or the intensity. Look for easy ways to add extra time – take the stairs instead of the elevator, park in the furthest row in the parking lot from the building, try to walk for some errands instead of driving.

6. Warm up!
Take 5 to 10 minutes at the beginning of each exercise session to warm up and decrease your risk of injury. Start with brisk walking or a slow jog to raise your heart rate followed by a gentle stretching routine.

7. Fill up the fuel tank and stay hydrated
You wouldn’t start driving on a long trip on an empty gas tank, and the same holds true for exercise. Try to eat a snack or small meal 30 to 60 minutes before a workout, especially in the morning. Remember to stay well hydrated. Even a small amount of dehydration can impact your exercise tolerance and performance. Athletes notice significant effects with as little as 2-3% dehydration/ Drink water for workouts less than 30 to 45 minutes. Try a sports drink with carbohydrate and electrolytes for exercise lasting longer.

8. Cross Train
Find several different exercise routines to keep interested and refreshed. Try to mix up aerobic exercise (jogging, cycling, or swimming) with resistance (weightlifting) and stretching. Vary the routes, distances and intensity throughout the week.

9. Get a workout partner
It’s easy to make excuses to yourself and skip a workout. Its harder to skip that workout if someone else is depending on you to be there – so find a workout partner that shares some of your fitness interests.

10. Rest and recovery – are important components to a successful workout program. Give your body time to rest, heal and recovery from your workouts and you will experience less injuries.

Exercising while sick

With the cold and flu season upon us, a common question we hear from athletes is recommendations for exercising when ill. There is some misinformation out there that suggests trying to “sweat out” a cold or flu. However, that exercise could be doing more harm than good when you’re sick.

While regular and moderate exercise such as light jogging has been shown to boost immune system function, more vigorous exercise such as a hard tempo run, intervals or racing temporarily suppresses the immune system up to 24 hours after exercise.

Immune system suppression may lead to a worsening infection such as pneumonia or bronchitis, or even an infection of the heart muscle (myocardium) called myocarditis that can be life threatening or fatal.

One easy piece of advice is to remember the “neck check” in determining whether to exercise during an illness or not. If your symptoms are mild and isolated to the neck and above, such as a runny nose or sore throat, then you’re probably ok for light to moderate workouts. If the symptoms are below the neck- fever, muscle aches and pains, productive cough, or diarrhea, then consider holding off and rescheduling your workouts.

How fast can you return to a full workout schedule? Start back at about fifty percent of your normal exercise distance or time at a reduced intensity. Also allow extra recovery time between workouts. A proper amount of rest is important to a quicker recovery. Listen to your body and if you’re finding that you fatigue quickly, continue to limit your exercise time, duration and intensity.