17 Jan 2014

How does caffeine affect the body & athletic performance?

All Articles, Nutrition Advice 10 Comments
coffeeThere are a couple of different things to weigh up when considering this question….namely what are the short term performance benefits of caffeine versus the long term health implications of consistently consuming high levels of caffeine on the body.The changes caffeine makes in your physiology can have both positive and negative consequences.
Positive
  • Studies have shown that caffeine can enhance physical performance and endurance, providing it isn’t overused.
  • Caffeine speeds up metabolism, so it can help to break down fat more efficiently if consumed prior to exercise
Negative
  • Caffeine is not an energy provider. It is a central nervous system stimulant drug that produces mild positive mood changes. Caffeine elevates the level of certain hormones – adrenaline, cortisol (stress hormone), adenosine and dopamine. This gives a temporary boost, but after the caffeine wears off, the body can feel fatigued and feelings of mild depression can set in.
  • Sleep: Caffeine can affect your sleep by keeping you awake longer, thereby shortening the amount of sleep you get, and giving you less time in the restorative stages of sleep, which takes a toll on your level of alertness the next day and overall health.
  • Weight: Many experts believe that increased levels of cortisol lead to stronger cravings for fat and carbohydrates, and cause the body to store fat in the abdomen.
  • Dependence: At doses of around 100mg daily (2 cups of coffee) caffeine has been shown to produce physical dependence characterised by lethargy and headache on cessation of intake.
  • Nutrient Leeching: Caffeine leeches nutrients from the body. For instance caffeine leeches B vitamins, which are energy-releasers. Orbana contains high concentrations of energy-releasing B vitamins, so it would not be desirable to have caffeine in Orbana, as the caffeine would negate the benefits of the B vitamins. This also brings into question the wisdom having B vitamins in caffeinated beverages.
  • Iron: Caffeine consumption has been shown to reduce the body’s ability to absorb iron.

So the overall message here is that caffeine can enhance physical performance in the short term and can be effective if used sparingly in this instance. However, the long term implications of consuming high levels of caffeine can be very damaging.

Our philosophy is to promote long term good health and thereby would boost performance both immediately and over a period of time. We feel that this would be best achieved by avoiding caffeine and artificial sweeteners and preservatives in energy drinks entirely.

This is not to say that caffeine cannot be beneficial. The question is more about quantity and other lifestyle factors.

The guidelines to caffeine intake are:

  • Limit your caffeine intake to less than 60mg a day (about 1 cup of coffee)
  • Try to avoid caffeine after 2pm. Caffeine stays in your system for 8 hours and disrupts sleep, so if you take it after 2pm it will more than likely disrupt sleep patterns
  • If you are stressed already and thus already have high levels cortisol it is best to avoid caffeine – which further increases cortisol levels and will have a detrimental effect on sleep and mood.

So if you are not stressed and you don’t have a high caffeine intake otherwise, you could gain benefit by taking a smallish amount of caffeine before exercise. We think most people lead stressful lives and often rely on caffeine to get them through their day and therefore is best avoided in energy drinks.

Share your comments and questions about caffeine in sports and energy drinks below!


  • Joe Winyard (via Imogen)

    Can drastically numb ‘perceived effort’ and ‘pain’ but only when taken in high quantity. Great for alertness too, but with most ‘advantages’ in sport I think some of it is down to placebo. Also, the body builds up a tolerance to caffeine if it’s taken regularly, thus becoming less effective. Long term use can’t be good for health.

    • Dan

      Agreed. I don’t think long term use of caffeine can be good for health. Do you ever use caffeine or any other products to boost your performance?

  • Charles

    Caffeine is a mild stimulant and I doubt makes any difference to physical fitness. It also enhances analgesics which is why it is often mixed with Paracetamol and Codeine. Some people say it is an analgesic in its own right as may be Glucosamine but that’s another story.

    • Dan

      It is true caffeine is a mild stimulant. However, the IOC still lists caffeine as a restricted drug. Approximately 1000mg of caffeine (about 8 cups of coffee) would be required to exceed the current IOC limit, but it is very important to note that people can metabolize caffeine at very different rates. Differences in metabolism, medications, and certain diseases may significantly alter the rate in which caffeine is cleared from the body. Some athletes have come close to flunking the drug test after ingesting only 350mg. It is wise to consider this before using caffeine as an ergogenic aid. There is certainly evidence that caffeine enhances the effect of analgesics such as paracetamol. So what’s the story with glucosamine?

  • Russ Collins

    I tried it when i was training for a triathlon last year. i was swimming the usual 1.5 miles at the pool but kept needing to get out for the loo! This is because caffiene is a diuretic, also felt really sick and nauseous afterwards. id taken an ‘energy supplement’ i bought at holland and barrett that had a very high caffeine content. Would not recommend it at all! Just stick to your normal training diet as far as im concerned there are no short or long term benefits of caffeine for sports related activities.

    • Dan

      Caffeine is indeed a diuretic, and a very high caffeine energy supplement would likely cause you to need to go the toilet. Can I ask what supplement you took? Supplements/energy drinks can still be useful, but only when they contain the right balance of ingredients to improve performance, and don’t contain large amounts of artificial stimulants.

  • Amy

    I find your comments on the negative side effects particularly interesting; the effect I find most annoying is the disruption to my sleep. Something not mentioned here is that caffeine has been found to increase blood pressure and heart rate, which in turn increases stress levels throughout the day. On a daily basis, over a sustained period of time this can then lead to increased risk of coronary heart disease and stroke.

    Surely if caffeine increases your heart rate and then exercise increases this further still, taking caffeine just before exercise can’t be great for the heart?

    Source: July/August issue of the journal Psychosomatic Medicine.

    • Dan

      The disruption to sleep is a huge negative effect. I would agree that daily caffeine consumption is to be avoided, along with the accompanying increase in blood pressure, particularly in the long term. The long term effect of caffeine on blood pressure is still unclear.

  • Imogen

    So as a positive you say that caffeine speeds up metabolism, so helps breaks down fat more efficiently. Does this mean it can be used as a weight loss aid?

    • Dan

      Caffeine elevates cortisol hormone levels which some experts believe contributes towards long term weight gain – so no this wouldn’t be a reason to use caffeine during exercise as a weight loss aid.