Check out what's up and coming

News Details

A Kick of Caffeine
Posted date: 16-Sep-2015

Can a cup of coffee really help you go faster?



Coffee culture has been around in Singapore long enough to become part of the scenery. It has become a centre of life for many Singaporeans, both young and old. With cafes sprawling in the heartlands, it is easy to get one’s caffeine fix these days. Recently, coffee has also been seen appearing in sporting arenas such as CrossFit gyms.


Caffeine is being promoted these days as an ergogenic aid. It is true that caffeine has been used to improve athletic performances and precipitate weight loss in the past. However, there were doubts and many uncertainties in the past.


Today, the general consensus in the scientific community is that it is effective after substantial evidence-based clinical studies. Furthermore, the strongest evidence for using caffeine as an ergogenic aid can be found in middle-distance endurance sports.


Research investigating the effects of caffeine on a timed trial with trained cyclists found that 5 mg of caffeine per kilogram of body weight improved speed, peak power, and mean power. Other studies have shown that swimmers and rowers who engage in high-intensity activities lasting one to 20 minutes can benefit from a more moderate dose of 2 to 3 mg of caffeine per kilogram of body weight. However, adverse effects such as rapid heart rate, dizziness, and feelings of hypoglycaemia such as lightheadedness and jitteriness have been observed when caffeine is taken in larger quantities or for athletes who are caffeine sensitive.


However, one has to be cautious that caffeine does not work in the same way for everyone. Some athletes may find that it makes them jittery, anxious, or hyperactive. For others, caffeine can prompt bowel movements. Studies report caffeine also may elevate blood pressure and heart rate. The day of a big competition is really no time for an athlete to learn how caffeine will affect them.


Generally, caffeine is safe when taken in recommended doses and can be an effective ergogenic aid to improve endurance and high-intensity activity lasting up to 20 minutes.



Optimal Caffeine Intakes


So here is what you are probably waiting for; just how much should I consume? Show me some figures!


The optimal intake for caffeine before a big race depends upon two factors: your tolerance and your size.  If you are a regular caffeine user, more caffeine will be required to get the same boost as someone who uses it infrequently. Your weight matters too, so use this formula to determine your optimal caffeine intake range:


(Weight in Kg) x 2 x 1.5 = low range of consumption (in mg)

(Weight in Kg) x 2 x 3.0 = high range of consumption (in mg)


So, if you weigh 75 kg, your range will be 225 mg – 450 mg.  Here is a list of body weights and optimal caffeine ranges:

  • 50 kg = 150 – 300 mg
  • 60 kg = 180 – 360 mg
  • 70 kg = 210 – 420 mg
  • 80 kg = 240 – 480 mg
  • 90 kg = 270 – 540 mg
  • 100 kg = 300 – 600 mg
  • 120 kg = 330 – 660 mg

You might want to ingest caffeine about 1 hour before you race.  You should aim for the low end of the range if you’re an infrequent caffeine or low-dose consumer (1 cup of coffee per day).  The higher range would apply to a more consistent caffeine user (3 cups or more of coffee per day).  The higher parts of the ranges do require a fairly large dose of caffeine.


Despite what many people have claimed, caffeine in moderate amounts has not been found to be dehydrating.  Laboratory tests have uncovered no difference in urine output in athletes drinking as much as 5 cups of coffee, as compared to 5 cups of water.



Caffeine Sources


Use the following list for how much caffeine is in various sources:

  • Coffee (8 oz) – 130 mg avg (100-200 mg range)
  • Espresso (1 oz) – 40 mg avg (30-90 mg range)
  • Coca-Cola (330 ml) – 34 mg
  • Mountain Dew (330 ml) – 55 mg
  • Red Bull (330 ml) – 105 mg
  • Black Tea (250 ml) – 50 mg (40-120 mg range)
  • Green Tea (250 ml) – 25 mg (20-60 mg range)

Experiment during training to learn what amount (if any) works best for your body! More is not always better.


Note: No amount of caffeine will compensate for a lousy diet. If you choose to use caffeinated products to enhance your sports performance, make sure you are also fueling wisely!




Text: Clement Gan


This interview was originally published in RUN Singapore. Besides the print edition published bimonthly, selected stories can also be found online at