According to the British Coffee Association, caffeine before a workout will make you more alert, improve your motor skills, give you renewed vigor, increase your output level and help you be more persistent. Plus you'll be able to perform 30% longer.
The caffeine reduces the chemical messages in your brain that normally induce fatigue and instead stimulates energy production and fat oxidation.
Having said that, there are also negative effects related to caffeine such as insomnia, anxiety, headaches, heart palpitations and high blood pressure.
So how much caffeine per day will keep you free from the negative effects?
Most health experts recommend that you have no more than 400 milligrams a day.
One cup of coffee contains approximately 100 mg so you should drink no more than 4 cups of coffee each day.
Mind you that's four cups of coffee if during your day you don't drink a soft drink (a 12 fl oz (368 g) has 29 mg of caffeine) or an energy drink (a Five Hour Energy Drink has 200 mg of caffeine; a 10 Hour Energy Shot has 422 mg of caffeine).
When it comes to coffee, you should drink coffee one hour before your morning or lunchtime exercise (if you exercise in the afternoon or evening, a coffee with lunch will suffice).
Note: It's recommended that pregnant women consume no more than 200 mg of caffeine per day (or about two cups of coffee).
Quote: - "I like coffee because it gives me the illusion that I might be awake." - Lewis Black