3. Studies on the effectiveness of caffeine intake during physical activity
When looking at any studies on caffeine, it must be borne in mind that the test group should have the same or similar caffeine metabolism. The results of studies can be very extensive in terms of effect. It is sufficient that the study group is not defined by the classification conditions and that participants have a very varied caffeine absorption metabolism. However, the effect of intake will ALWAYS be the same – improving both performance and endurance. The only difference will be in how susceptible the test subject’s body will be to its effects, and therefore how much it will improve its performance.
The effectiveness of caffeine has been known for many years. Using low doses of caffeine has an ergogenic effect through interaction with the CNS. This results in a minimal improvement in the response to the exercise response and low doses of caffeine do not have a high risk of side effects.
However, like any medically known substance, it has its own threshold, which, when exceeded, will give side effects:
- anxiety,
- accelerated heart rate,
- excessive agitation,
- fear,
- Diuretic effect,
- increased intestinal peristalsis,
- nausea,
- vomiting,
- the deterioration of sporting performance.
Initially, all tests were carried out in such a way that the test group consumed several cups of espresso and usually performed training on a cycloergometer until exhausted – so-called Time to Exhaustion. It was used to compare the effect of caffeine and how long it took for the test person to be unable to continue the test.
Currently, caffeine also occurs in the form of gels, bars, chewing gums, pills, energy drinks. This may improve the rate of caffeine absorption from the intestines into the blood and cheek mucosa. Even a form of mouthwash with a solution containing caffeine and carbohydrates is tested.
Nowadays, forms of caffeine administration are tested to make them work even faster. Currently, a very popular method is the supply of chewing gums with caffeine, and even oral sprays containing caffeine. The idea is to reduce the time it takes for caffeine to absorb and overcome the blood-brain
barrier through the cheek / nasal mucosa.
One of the studies on the influence of caffeine-containing chewing gum and additionally the administration of beetroot juice to the study group.
Test group – 12 well-trained men and women (total 24)
The subjects were divided and caffeine in the amount of 3mg / kg of body weight or placebo gum was administered.
The subjects were to cover M-43.83km and K-29.35km as soon as possible. It was to be a simulation of IO 2012 in London – one of the stages. It was supposed to last 50-60 minutes.
The subjects were given 2mg of caffeine / kg b.w. in chewing gum for 10 minutes (40 minutes before the test was completed) and then chewing gum with caffeine content of 1mg / kg b.w. for 10 minutes before the test.
The test was also carried out using beetroot juice and beet juice + caffeine.
The results of the test in men and women were similar. The administration of caffeine and caffeine + beetroot juice improved sports performance by 3-4% compared to placebo.
Beetroot juice alone did not affect performance.
Over the years we can expect a number of similar studies involving just the above mentioned mouth sprays. So far, there is no clear evidence that the aerosols significantly accelerate caffeine absorption, and there is a very high risk of overdosing.