Fast Facts on Caffeine: Performance Benefits for Athletes
Introduction
Don't expect to see an espresso machine at an aid station during your next event, but there's a growing amount of research indicating caffeine can improve your performance.
So if you're now thinking “Hey, I can set a PR if I hit a Starbucks before my next race,” you should read on and learn about the beneficial effects of caffeine.
Legitimate Benefits?
Once thought to be a ‘nutrition no-no' for athletes, caffeine has taken center stage in the past few years as a legitimate aid to performance. This benefit has been recognized by the makers of sports nutrition products like energy gels.
A growing body of laboratory research supports caffeine as an effective ergogenic aid. (An ergogenic aid is a substance that improves athletic performance.) The most dramatic performance improvements (20-50 percent) are seen during prolonged (over two-hours) endurance exercise (3,4,7,8,9,12). Caffeine is also reported to benefit short-term intense exercise lasting about five minutes at maximal output (1,2,10,11).
How Caffeine Can Work for You
To maximize the benefits of caffeine, an athlete should consume 3-6 mg of caffeine per kilogram of body weight (roughly 2 mg/lb. of body weight) about one hour prior to exercise. For example, a 120-lb. person should consume roughly one to two cups (8 oz.) of drip-percolated coffee. A 175-lb. person would need to drink two to four cups. (Carb-BOOM!'s Vanilla Orange and Chocolate Cherry each contain approximately 50 mg. of caffeine.) See Chart 1 for caffeine content of other common foods/drinks.
The majority of lab research shows ingesting caffeine one hour before exercise results in enhanced performance. Few studies have been done on the possible ergogenic effects of caffeine ingestion during exercise. Although scientific research is still slim in this area, many endurance athletes believe that ingesting caffeine during prolonged exercise gives them an extra mental perk, increased focus and refreshed motivation.
Caffeine is well-known as a diuretic, therefore, it's reasonable to assume that athletes might have concerns about its effects on hydration. However, several studies conclude that no changes occurred in core temperature, sweat loss, plasma volume, urine volume or body hydration status during exercise following caffeine ingestion (5,6).
The Chemistry of Caffeine
The exact mechanism(s) of caffeine's ergogenicity remains unclear. More research is needed to fully elucidate the answer; however, three main theories exist.
Central Nervous System
This explanation involves the central nervous system (CNS). Caffeine stimulates the CNS, which would positively affect the athlete in two ways: through perceived exertion and through increased neural activation of muscle contraction.
Explained in more simple terms, caffeine ingestion may help the athlete ‘feel' better and more alert. So a boost of caffeine might make mile 19 of a marathon or starting the third leg of a triathlon feel not as hard. Along with this enhanced focus and clear-headedness, caffeine affects the CNS by stimulating the nerves to fire muscles into action more effectively.
Skeletal Muscle
The second theory focuses on the direct effect caffeine has on skeletal muscle performance. Caffeine produces changes in calcium activity, which stimulates the ion transport of potassium into non-contracting tissues. The ion transport leads to a reduction of the typical rise in plasma potassium concentrations occurring during exercise. It is thought that lowered potassium levels in the plasma help to maintain the excitability of the muscle fiber. More simply put, caffeine may benefit the athlete by helping to produce a longer (and possibly stronger) muscle contraction.
Metabolism
The third theory involves the ‘classic' metabolic explanation of caffeine's benefit to exercise performance. Caffeine increases the release early in exercise of free fatty acids into the blood. The increase in fatty acid availability leads to increased muscle fat oxidation and decreased carbohydrate oxidation, thus sparing muscle glycogen for use later in exercise. The extra store of glycogen benefits the athlete by delaying the onset of fatigue.
None of the above three theories alone can fully explain the ergogenic effect of caffeine. Different types of exercise (endurance versus short term) probably see performance improvements from different mechanisms (metabolic versus muscle). Another explanation may be that caffeine ingestion affects changes in the central nervous system, skeletal muscle, and metabolism, so that all three mechanisms work together in some capacity to benefit exercise performance.
Give It a Shot!
If you haven't tried caffeine as part of your training/racing regimen it's worth a shot! You may see an improvement in your race times as a result. Keep in mind that variability can be large. Regular caffeine users may see different responses than non-caffeine users and females may vary from males. You'll need to experiment to find out what works best for you. Try ingesting caffeine prior to exercise, during exercise and a combination of both. Experiment with caffeine during a long training bout versus a short interval-type workout. It may take a few training sessions to figure out the optimal timing and dosage for your body, but achieving a new PR might just be the end reward.
Fast Facts On Caffeine and Exercise
Caffeine ingestion can benefit endurance performance when consumed in proper amounts (2 mg/lb. of body weight) approximately one hour prior to exercise.
Timing is important. The benefits of ingesting caffeine approximately one hour prior to exercise are well supported. The benefits of caffeine ingestion during exercise is less clear.
Caffeine is no longer a banned substance as designated by the IOC.
Athletes need not worry about any adverse diuretic effects of caffeine
Caffeine content of common foods & drinks
Energy Gels Caffeine Serving Size
Carb-BOOM!
(Vanilla, Chocolate flavors) 50 mg 1.4 oz
Clif Shot 40 mg 1.1 oz
PowerGel 25-50 mg 1.4 oz
Gu 20 mg 1.1 oz
Soft Drinks
Coca-Cola 45 mg 12 oz
Mountain Dew 55 mg 12 oz
Barq's Root Beer 22 mg 12 oz
Pepsi Cola 37 mg 12 oz
Dr. Pepper 42 mg 12 oz
Coffee
Drip-percolated 85-130 mg 8 oz
Instant 75-95 mg 8 oz
Starbuck's ‘Short' 250 mg 8 oz
Teas
Black tea 40-50 mg 8 oz
Green Tea 20-30 mg 8 oz
Snapple Iced Teas 21 mg 8 oz
Arizona Iced Tea 16 mg 8 oz
Chocolate
Chocolate Milk 5 mg 8 oz
Hot Cocoa 5 mg 8 oz
Milk Chocolate 6 mg 1 oz
Dark Chocolate 20 mg 1 oz
Introduction
Don't expect to see an espresso machine at an aid station during your next event, but there's a growing amount of research indicating caffeine can improve your performance.
So if you're now thinking “Hey, I can set a PR if I hit a Starbucks before my next race,” you should read on and learn about the beneficial effects of caffeine.
Legitimate Benefits?
Once thought to be a ‘nutrition no-no' for athletes, caffeine has taken center stage in the past few years as a legitimate aid to performance. This benefit has been recognized by the makers of sports nutrition products like energy gels.
A growing body of laboratory research supports caffeine as an effective ergogenic aid. (An ergogenic aid is a substance that improves athletic performance.) The most dramatic performance improvements (20-50 percent) are seen during prolonged (over two-hours) endurance exercise (3,4,7,8,9,12). Caffeine is also reported to benefit short-term intense exercise lasting about five minutes at maximal output (1,2,10,11).
How Caffeine Can Work for You
To maximize the benefits of caffeine, an athlete should consume 3-6 mg of caffeine per kilogram of body weight (roughly 2 mg/lb. of body weight) about one hour prior to exercise. For example, a 120-lb. person should consume roughly one to two cups (8 oz.) of drip-percolated coffee. A 175-lb. person would need to drink two to four cups. (Carb-BOOM!'s Vanilla Orange and Chocolate Cherry each contain approximately 50 mg. of caffeine.) See Chart 1 for caffeine content of other common foods/drinks.
The majority of lab research shows ingesting caffeine one hour before exercise results in enhanced performance. Few studies have been done on the possible ergogenic effects of caffeine ingestion during exercise. Although scientific research is still slim in this area, many endurance athletes believe that ingesting caffeine during prolonged exercise gives them an extra mental perk, increased focus and refreshed motivation.
Caffeine is well-known as a diuretic, therefore, it's reasonable to assume that athletes might have concerns about its effects on hydration. However, several studies conclude that no changes occurred in core temperature, sweat loss, plasma volume, urine volume or body hydration status during exercise following caffeine ingestion (5,6).
The Chemistry of Caffeine
The exact mechanism(s) of caffeine's ergogenicity remains unclear. More research is needed to fully elucidate the answer; however, three main theories exist.
Central Nervous System
This explanation involves the central nervous system (CNS). Caffeine stimulates the CNS, which would positively affect the athlete in two ways: through perceived exertion and through increased neural activation of muscle contraction.
Explained in more simple terms, caffeine ingestion may help the athlete ‘feel' better and more alert. So a boost of caffeine might make mile 19 of a marathon or starting the third leg of a triathlon feel not as hard. Along with this enhanced focus and clear-headedness, caffeine affects the CNS by stimulating the nerves to fire muscles into action more effectively.
Skeletal Muscle
The second theory focuses on the direct effect caffeine has on skeletal muscle performance. Caffeine produces changes in calcium activity, which stimulates the ion transport of potassium into non-contracting tissues. The ion transport leads to a reduction of the typical rise in plasma potassium concentrations occurring during exercise. It is thought that lowered potassium levels in the plasma help to maintain the excitability of the muscle fiber. More simply put, caffeine may benefit the athlete by helping to produce a longer (and possibly stronger) muscle contraction.
Metabolism
The third theory involves the ‘classic' metabolic explanation of caffeine's benefit to exercise performance. Caffeine increases the release early in exercise of free fatty acids into the blood. The increase in fatty acid availability leads to increased muscle fat oxidation and decreased carbohydrate oxidation, thus sparing muscle glycogen for use later in exercise. The extra store of glycogen benefits the athlete by delaying the onset of fatigue.
None of the above three theories alone can fully explain the ergogenic effect of caffeine. Different types of exercise (endurance versus short term) probably see performance improvements from different mechanisms (metabolic versus muscle). Another explanation may be that caffeine ingestion affects changes in the central nervous system, skeletal muscle, and metabolism, so that all three mechanisms work together in some capacity to benefit exercise performance.
Give It a Shot!
If you haven't tried caffeine as part of your training/racing regimen it's worth a shot! You may see an improvement in your race times as a result. Keep in mind that variability can be large. Regular caffeine users may see different responses than non-caffeine users and females may vary from males. You'll need to experiment to find out what works best for you. Try ingesting caffeine prior to exercise, during exercise and a combination of both. Experiment with caffeine during a long training bout versus a short interval-type workout. It may take a few training sessions to figure out the optimal timing and dosage for your body, but achieving a new PR might just be the end reward.
Fast Facts On Caffeine and Exercise
Caffeine ingestion can benefit endurance performance when consumed in proper amounts (2 mg/lb. of body weight) approximately one hour prior to exercise.
Timing is important. The benefits of ingesting caffeine approximately one hour prior to exercise are well supported. The benefits of caffeine ingestion during exercise is less clear.
Caffeine is no longer a banned substance as designated by the IOC.
Athletes need not worry about any adverse diuretic effects of caffeine
Caffeine content of common foods & drinks
Energy Gels Caffeine Serving Size
Carb-BOOM!
(Vanilla, Chocolate flavors) 50 mg 1.4 oz
Clif Shot 40 mg 1.1 oz
PowerGel 25-50 mg 1.4 oz
Gu 20 mg 1.1 oz
Soft Drinks
Coca-Cola 45 mg 12 oz
Mountain Dew 55 mg 12 oz
Barq's Root Beer 22 mg 12 oz
Pepsi Cola 37 mg 12 oz
Dr. Pepper 42 mg 12 oz
Coffee
Drip-percolated 85-130 mg 8 oz
Instant 75-95 mg 8 oz
Starbuck's ‘Short' 250 mg 8 oz
Teas
Black tea 40-50 mg 8 oz
Green Tea 20-30 mg 8 oz
Snapple Iced Teas 21 mg 8 oz
Arizona Iced Tea 16 mg 8 oz
Chocolate
Chocolate Milk 5 mg 8 oz
Hot Cocoa 5 mg 8 oz
Milk Chocolate 6 mg 1 oz
Dark Chocolate 20 mg 1 oz
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