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Caffeine And Athletic Performance

What is it? Caffeine is found in coffee, tea, chocolate, cola drinks, and some medicines. It is a stimulant (stih-mew-lunt) because it helps people stay awake. It also increases the heart rate and blood pressure.

How does caffeine effect a person's ability to do sports activities?

  • Caffeine effects each person differently. Some people feel like they have more energy and can exercise harder and longer if they have caffeine first. Caffeine makes other people feel too jittery or nervous to do well during sports activities.
  • Studies have found that 200 to 350 milligrams (mg) of caffeine helped some people have more endurance (able to exercise longer). This may be caused by caffeine making the body use fat as fuel instead of glycogen (stored sugar). Or, caffeine may effect the brain by making athletes less aware of being tired. If taken in moderate amounts, caffeine may give you a mental edge for competing. It may also improve your mood and make you feel more like working out on a regular basis.

Can caffeine cause unwanted side effects?

  • Most importantly, caffeine can cover up the fact that your body needs more rest. Pay attention to your body and take time to recover from exercise.
  • Caffeine is also a diuretic which means it can make you urinate more than usual. If this is a problem for you, lower the amount of caffeine you are taking. Also, drink more liquids for 2 to 3 days before a sports competition.
  • Drinks with caffeine can cause your bowels to move sooner than usual especially if taken in the morning,. This can be helpful before competing in sports. But, be careful to time it right so you do not have problems during the competition. Caffeine may give you diarrhea if exercise already causes you to have loose BMs. Some people also have nausea (upset stomach) or indigestion (sour stomach) if they take too much caffeine before hard exercise. You must figure out what amount of caffeine is right for you and take it at the right time before exercising.
  • It may not be good for you to take caffeine if you are nervous or get pre-event jitters. Caffeine can make you more nervous, cause muscle shakiness, and make it hard to concentrate.
  • High levels of caffeine use, such as 800 mg per day, have been banned by the International Olympic Committee and other institutions. Most people can stay in the allowed limits by taking less than 350 mg per day.

How do I know how much caffeine is in food and drinks? Caffeine is measured in milligrams (mg). Many foods and drinks have the exact amount of caffeine in them listed on the side of the package. Use the lists below to measure the approximate amount of caffeine in common foods and drinks. Ask your caregiver or dietitian if you want to know the amount of caffeine in items not on this list.

  • Coffees:
    • 8 oz. cup of brewed coffee (130 to 175)
    • 8 oz. cup of instant coffee made with water (70 to 135)
    • 8 oz. cup of international coffees from powders (55 to 70)
    • 5 oz. cup of espresso (150)
    • 8 oz. cup of decaffeinated brewed coffee (3 to 6)
  • Teas:
    • 6 oz. cup of black tea brewed 3 minutes (40 to 60)
    • 8 oz. glass of iced tea, from powder (30 to 60)
    • 6 oz. cup of green tea (35)
  • Sodas:
    • 12 oz. can of cola, diet or regular (40 to 50)
    • 12 oz. can of citrus pop with caffeine (45 to 55)
    • Some soft drinks will state that they are caffeine-free on the side of the can.
  • Chocolates:
    • 6 oz. cup of hot chocolate (5 to 10)
    • 8 oz. glass of chocolate milk (10)
    • 1 oz. baking chocolate (35)
    • 1 oz. semi-sweet chocolate (20)
    • 2 oz. sweet chocolate (15)

Do some medicines contain caffeine? Listed below are some common medicines that contain caffeine.

  • Allergy and cold pills (15 to 30)
  • Diuretics (water pills) (200)
  • Appetite suppressants (150 to 200)
  • Stimulants for drowsiness (150 to 200)
  • Pain relievers (30 to 130)
  • Other prescription drugs (35 to 100) (See the package label or insert.)

How do I know how much caffeine is right for me? Ask your caregiver before using caffeine to improve your ability to do sports. It is especially important to talk with caregivers if you do not usually drink coffee or other things with caffeine.

  • Start with a small amount if you decide. Try 50 to 100 mg of caffeine at first and slowly increase from there. Most people get the best results by taking 100 to 300 mg of caffeine in the two hours before working out. The highest amount that most people can tolerate before hard exercise is 350 mg.
  • Another way to figure the best amount of caffeine for you is to take it according to how much you weigh. Take 2 to 4 mg of caffeine for each kilogram (kg) of your body weight. Divide your weight in pounds by 2.2 to figure out how much you weigh in kilograms. For example, a 154 pound athlete weighs 70 kilograms and could take 140 to 280 mg of caffeine.

Care Agreement

You have the right to help plan your health care. To help with this plan, you must learn about using caffeine to help you exercise better. Work with your caregivers to decide whether using caffeine is right for you. You always have the right to refuse treatment.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.