The Effects of Caffeine on Exercise Performance

By WLR Staff, by Kelly Olsen

One look at the queue in your local coffee shop or coffee machine at work will convince anyone that a huge amount of coffee is consumed daily.

As one of the most widely used stimulants in the world, caffeine occurs naturally in foods and drinks, like tea, coffee and chocolate. It is also added to medicines for colds, aspirin and weight loss products.

So a cup of coffee may well get us going in the mornings and if we order a ‘skinny’ latte we might feel even a little virtuous, but what are the effects of getting your daily shots of caffeine on fitness?

General Effects of Caffeine

Caffeine basically gives us a jolt and in the US it is estimated that over 10% of people drink 10 cups per day.

In scientific terms caffeine blocks adenosine which is a neurotransmitter that normally has a calming effect on the body. This causes adrenaline to be released which in turn raises your heart rate, tightens your muscles, dilates your pupils and the body releases extra glucose into your body for extra energy – hey presto the caffeine buzz.

That’s not all, the pleasure parts of your brain are also stimulated through the increase in dopamine, which is the usual suspect for explaining why we become addicted to caffeine.

Sounds good doesn’t it? The physiological affects of having that cup of coffee makes you feel really energetic and alert from the pumping of adrenaline around your body and the dopamine is making you feel really good – have another espresso!

On the down side caffeine does have some side effects such as irritability and being unable to sleep and high doses can cause irregular heart beat.

Often people have been advised to avoid caffeinated drinks prior to exercise due to its diuretic effect.

Most studies now show that unless taken in huge quantities, say 8 cups in one sitting, this is not the case. There has also been some association with increased risk of osteoporosis in postmenopausal women.

Does Caffeine Affect Exercise Performance?

Caffeine has no nutritional value and is referred to as a ‘nutritional ergogenic aid’.

When it is ingested it is very quickly absorbed by the body – usually within 1 – 2 hours.

Research by the American College of Sports Medicine has shown that ingesting 3-9 mg per kilogram of body weight (2-6 cups of regular coffee) approximately 1 hour before exercise can increase endurance or help with short intense exercise (around 5 minutes) where the person is working at near maximum.

The belief is that it has an effect on muscle contraction during anaerobic exercise – remember though this was tried on well-trained athletes in a laboratory environment.

Studies on elite distance runners and swimmers did show an increase in their performance times after they had ingested caffeine. The Australian Institute of Sport team found that caffeine triggers the muscles to start using fat as an energy source rather than carbohydrate sugars.

Certainly the enhanced performance using caffeine has been well documented and the Olympic Committee banned athletes from having more that 12 mg/ml in their urine samples. This equates to approximately 4 – 7 cups of coffee consumed within 30 minutes.

Why is Endurance Improved with Caffeine?

Well, it has not been proven, but the common explanation is that endurance is improved although no studies have shown an increase on caffeine’s ergogenic effect on athletic performance, although habitual caffeine drinkers experience less effect that people who do not consume it regularly.

The common explanation to why endurance is improved with caffeine is that muscle glycogen is spared, as once muscle glycogen is depleted you cannot exercise to your full potential. Glycogen sparing, caused by caffeine ingestion, helps stop the body from using up all the glycogen in the muscles.

Is Coffee the Right Choice for a Pre-workout Drink?

Simple answer is yes with a ‘but’.

A recent Canadian study compared the effect of caffeine on running times and levels of exhaustion. Nine men took part in five trials. 1 Hour before each run the men took one of the following: A placebo, caffeine capsules, de-caffeinated coffee with caffeine added, regular coffee.

The results showed that the men taking the caffeine capsules increased their performance by up to 10 times. Whilst the levels of caffeine absorbed by all the men were the same during the trail, the belief is that with coffee itself the other ingredients and processes that form part of the roasting and grinding of coffee beans interfere with caffeine’s performance-enhancing effects, so caffeine capsules work better.

What About the Effects on Creatine?

Creatine is known to help with endurance and many people take supplements to enhance their performance.

Studies show that caffeine can completely counteract the effect of taking Creatine supplements. Advice to people taking Creatine as a supplement is to avoid caffeine found in food and drinks.

Conclusion…

Yes, caffeine could enhance your performance and some studies suggest it is up to 60%. This is not a replacement for a healthy diet and good hydration, all of which will definitely help you train better and reach your fitness goals.