Caffeine and Exercise: Can It Help with Performance?

Caffeine and Exercise: Can It Help with Performance?

Do caffeine and exercise create a winning combination for enhanced performance? Learn what caffeine is, how it affects the body, whether or not it has any bearing on your training sessions.

What is Caffeine?

Caffeine is the most widely used legal stimulant. It is a natural compound found in coffee beans, tea leaves, kola nuts that flavor soft drinks, and cacao pods used to make chocolate products.

Man-made synthetic forms of caffeine also exist in medicines, energy drinks, and energy-boosting gums and snacks [R].

How Does Caffeine Work?

Caffeine molecules stimulate the central nervous system by attaching to adenosine receptors in the brain.

The blocking motion of caffeine prevents that sleepy feeling given off by adenosine. Neurotransmitters dopamine, adrenaline, and glutamate are produced. These substances then activate a feeling of energy and alertness [R].

How Caffeine Is Consumed

The main source of caffeine consumption is in the form of chocolate products along with drinking coffee, tea, soda, and/or energy drinks [R].

Benefits of Caffeine and Exercise

Caffeine can have positive effects on workouts and athletic performance.

Research in sports medicine shows it to improve endurance, performance, and muscle building.

Caffeine and Exercise May Promote Weight Loss

Caffeine improves thermogenesis which increases fat burning and weight loss [R].

Caffeine and Exercise May Improve Physical Performance

Concentration, reduced fatigue, and enhanced alertness from daily caffeine intake may also positively improve physical performance [R].

Caffeine and Exercise Limited Effects on Muscle & Strength Training

Caffeine had little effect on muscle mass but improved strength in upper body muscles. High caffeine intake also benefited some exercises more than others. Chest press, bicep curl, leg extension, and triceps extension had better outcomes than leg presses, leg curls, and lat pulldowns. [R, R].

Non-athletes and habitual users of caffeine had no lean body mass increases after 12 weeks of full-body resistance exercise. High caffeine was associated with lower muscle performance [R].

Caffeine May Improve Exertion

One study examined self-perceived exertion during exercise. Caffeine decreased the exertion felt by exercise when compared with a placebo. Caffeine also improved exercise performance by 11.2% [R].

Caffeine May Improve Aerobic Capacity

Caffeine is thought to augment respiratory function. This means more blood flow to skeletal muscles increasing performance and output while also minimizing exertion [R].

Even habitual users may benefit from caffeine’s respiratory effects [R].

What To Look for In A Caffeine Supplement

Caffeine pills are not regulated so care should be taken when choosing a supplement. It is best to look for a natural caffeine source as opposed to a synthetic version.

Caffeine Dosage

Information on the best dose and type of caffeine is limited when it comes to testing athletic performance. More research needs to be done to find an optimal level of caffeine to get the best results.

Starting with a smaller dose of 100 - 200 mg of caffeine is best to see how it affects your body.

Risks and Contraindications of Caffeine and Exercise

Caffeine is relatively safe for most healthy people [R] but there are still some side effects, risks, and contraindications to be aware of.

Caffeine is a stimulant that increases heart rate and blood pressure [R]. Those with glaucoma, borderline, or high blood pressure may want to avoid caffeine supplements [R].

Taking more than 350 mg of caffeine can cause nutrient depletions and interfere with the absorption of calcium, iron, vitamin D, thiamin, and vitamin A. It is best to give the body an hour between caffeine consumption and these nutrients [R].

Caffeine affects everyone differently. Some people have no problems while others are bothered by just a small amount of caffeine.

Caution should be taken with supplements since they are a more concentrated form of caffeine.

Side effects of caffeine use include elevated heart rate, dehydration, blood pressure, disrupted sleep, headaches, irritability, nervousness, anxiety, and the jitters even up to 12 hours after consumption [R, R, R].

Dependence may also become a problem when using caffeine [R].

Final Thoughts on Caffeine and Exercise

The combination of caffeine and exercise has been shown to improve cognition, performance, and endurance in aerobic and some strength training activities. Caffeine is still a drug that causes side effects with even moderate consumption. Those on medications or with any health conditions should talk to their doctor before taking any caffeine supplements. More research needs to be done to know the true dose and type of caffeine needed to enhance physical performance.


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