Caffeine is probably the most common stimulant in the world. You find it in coffee and tea along with many energy drinks or pills. It originally comes from coffee beans, but can also be synthesized in the laboratory.
As a stimulant, caffeine can be used to improve physical endurance and strength. It works by engaging with the central nervous system (CNS), heart, muscles, and the centers that control blood pressure. This means it can raise blood pressure, something that people with sensitive blood pressure might want to keep in mind.
Long-term caffeine use will build up a tolerance in the body, so its effects will be diminished if you don’t stop taking it for a while. Usually, a month off is enough to get your sensitivity back to baseline.
What do caffeine supplements do?
Due to its many applications caffeine is used for a number of reasons both by athletes and normal people. Within sports, caffeine is one of the most commonly used stimulants and it’s actually allowed by the NCAA, as long as the urine concentrations stays under 15 mcg/mL. This is about 8 cups of coffee for most people.
Within fitness, you will usually see caffeine used for one of two purposes: Either for enhanced training or to increase metabolism.
Let’s look at both.
In regards to training, especially weight lifting, caffeine has been shown to improve endurance and strength. Caffeine drives blood away from the skin and other organs and into the muscles being immediately used, which slightly increases power.
What this means is that caffeine will allow you to push out more repetitions and more weight during your workout. Now depending on how advanced of a lifter you are and how your body is used to caffeine, this boost will range from a few percent up to 20 percent.
In regards to weight loss caffeine is most often sold as a metabolism booster. Now, even though I am usually very skeptic of weight loss pills and their ingredients, caffeine is one of the few substances that actually delivers results.
Several studies have shown that both caffeine and coffee stimulate the metabolic rate in healthy and overweight participants. 100 milligrams of caffeine are said to increase your basic metabolic rate by around 3-4%. If you follow a 2000 calorie diet this would be around 60–80 calories per day.
Do bigger doses boost your metabolism even more?
Maybe slightly, but you have to keep in mind that you can take too much caffeine. Going over your ideal dose will lead to headaches, anxiety, nausea, stomach cramps and problems falling asleep. Caffeine is a stimulant and should be treated as such. The more and longer you take it the higher the probability to develop negative side effects.
How should you take caffeine?
The ideal dose seems to lie within 100mg to 600mg for most people. If you are new to caffeine supplements, start at the low end of that range. 200mg of caffeine seems to be best for fat burning, while strength increases require a larger dose of around 500mg.
Caffeine levels in your blood peak around 60-90 minutes after consumption. Therefore, you should take it about an hour before your training.
Also, keep in mind that caffeine has a fairly long half-life of about six hours. That means if you take a 200 mg supplement at 6 p.m., you’ll still have half that amount in your system at midnight. That’s why I personally don’t take caffeine after 3 p.m.
Caffeine is generally safe when you use it correctly. That includes going off it every few weeks. It can lead to side effects when taken for a long time or in fairly high doses. Most common are insomnia, nervousness and increased heart rate.