Caffeine and Exercise: A powerful one-two punch for getting lean

You know that buzz, the feeling of energy you get from a cup of java. It’s enough to get your day started and give you the boost you need when heading to the gym. But as you engage your New Year’s training resolutions, there’s much more to know about caffeine and how it enhances performance.

Caffeine has long been known as a performance enhancer. In fact, from 1984 to 2004, the International Olympic Committee tested athletes for high levels of caffeine, which they considered a type of doping. But for you, caffeine still wins out as one of the safest performance boosters to enhance your workout.


Caffeine likely exerts its effects through stimulation of the central nervous system. It may cause an increased sense of awareness, decreased perception of effort, or may play a role in cellular level skeletal muscle contraction.

Weight Training (anaerobic)

• Dosages of 200 to 600 mg help you sprint faster, lift more weight or get more reps at the same weight, according to research.
• Performance-enhancing benefits of caffeine, however, can fade with frequent intake. This means you will need more to achieve the same effect.

Endurance Training (aerobic)

• Taking at least 100 to 200 mg of caffeine before your endurance workout may block A1 receptors, enabling you to exercise for a longer period of time.
• Since caffeine can also have a diuretic effect, be careful to drink plenty of fluids to ensure proper hydration, particularly in warm weather.


• Yes, caffeine can stimulate fat burning for a few reasons, particularly in the 200 mg range. First, since caffeine affects brain receptors you have more volitional energy to exercise longer and harder, which in turn burns more calories.
• Second, caffeine – through noradrenaline – stokes your metabolic furnace, again burning more calories.
• Third, caffeine activates the sympathetic nervous system, which in turn suppresses appetite.
• Fourth, caffeine helps mobilize lipids in fat cells so they can be used for energy, helping your body work more efficiently and depleting your fat stores.

Better Workout Recovery

• When you ingest caffeine with carbohydrates, you enable your body to store more glycogen (your body’s quick energy source).
• By taking in a caffeine/carb mixture you can enhance your performance in repeated exercise sessions, such as training more than once per day.
• That recovery will also make your muscle feel more full and ready for the next training session.


Caffeine affects habitual users differently than those who occasionally ingest. Habitual users can build up a tolerance, so individuals wishing to try caffeine as an ergogenic aid would do well to practice in advance, and not on the day of an important event. Often, habitual users preparing for a big contest will discontinue caffeine use and then reintroduce it to improve sensitivity about 1 week before the event.

When To Ingest

Caffeine peaks in your bloodstream between 30 and 75 minutes after ingestion, and half of it is gone in about 5 hours. So, timing of caffeine ingestion is critical. In endurance events, it is common to re-dose to get the desired effect.

And if all of this doesn’t convince you to be more thoughtful and deliberate about your caffeine ingest, then consider this: Habitual caffeine use is also associated with a reduced risk of Alzheimer’s, cirrhosis, and liver cancer.

Caffeine Content in Common Drinks

Caffeine Content Chart | Milligrams (mg) of Caffeine:
Coffee (8 oz) Brewed, drip method: Typical – 95 mg. Range* – 75-165 mg.
Instant Coffee: Typical – 75 mg. Range* – 60-85 mg.
Decaffeinated Coffee: Typical – 3 mg. Range* – 2-4 mg.
Espresso: Typical – 60 mg. Range* – 45-75 mg.
Teas (8 oz) Black: Typical – 47 mg. Range* – 14-70 mg.
Green Tea: Typical – 25 mg. Range* – 24-45 mg.
White Tea: Typical – 15 mg. Range* – 15 mg.
Instant Tea: Typical – 30 mg. Range* – 11-47 mg.
Iced Tea: Typical – 25 mg. Range* – 9-50 mg.
Soft Drinks (12 oz) Cola: Typical – 40 mg. Range* – 30-60 mg.
Citrus: Typical – 40 mg. Range* – 37-47 mg.
Energy Drinks (8 oz): Typical – 80 mg. Range* – 27-164 mg.
Cocoa Beverage (8 oz): Typical – 6 mg. Range* – 3-32 mg.
Chocolate Milk Beverage (8 oz): Typical – 5 mg. Range* – 2-7 mg.
Solid Milk Chocolate (1 oz): Typical – 6 mg. Range* – 1-15 mg.
Solid Dark Chocolate (1 oz): Typical – 20 mg. Range* – 5-35 mg.
Baker’s Chocolate (1 oz): Typical – 26 mg. Range* – 26 mg.
Chocolate Flavored Syrup (1 oz): Typical – 4 mg. Range* – 4 mg.

*Due to brewing method, plant variety, formulation, etc…
Source: Mayo Clinic.

About the Author: Bob LeFavi

Bob LeFavi, PhD, is a professor of sports medicine and Dean of the Beaufort Campus at the University of South Carolina, Beaufort. He has been department head of health sciences and sports medicine at Armstrong State University and Georgia Southern University, Savannah, GA. Bob won the bantamweight class at the IFBB NorthAmerican Bodybuilding Championship and was runner-up at both the USA and National Championships. He also competed in the CrossFit Games as a Master’s athlete and has written over 750 articles in the popular press on training, diet, and fitness.

Disclaimer: This content is for informational purposes only and is not meant as medical advice, nor is it to diagnose or treat any medical condition. Please consult your physician before starting or changing your diet or exercise program. Any use of this information is at the sole discretion and responsibility of the user.