Everything You Should Know About Coffee
1. Coffee Varieties
2. Nutritional Values Of Coffee
3. Is Coffee Dehydrating?
4. Coffee And Leaching Of Minerals
5. Coffee And Its Impact On Health
6. When And In What Quantities To Drink Coffee?
There is nothing better than a sip of freshly brewed coffee in the morning.
Many of us can not imagine starting day in a different way. A drink with a characteristic smell and unique taste. It is associated with a number of positive experiences, so it is not surprising that it is gaining a multitude of fans around the world.
A special group that likes coffee is the cycling community. Share on X
It is said that coffee and cycling are almost inseparable. What cycling lovers see in that unique, black beverage? Let’s take a closer look at this drink.
1. A Few Words About Coffee Varieties.
There are many varieties of coffee. The most common are Robusta and Arabica. As much as 70 percent of world production falls on the latter. Arabica is a very aromatic variety with a mild taste. It is a clean coffee, does not require any admixtures, and the caffeine content is low. This species is extremely difficult to grow due to the requirement of appropriate temperature and hydration. It is said that the best grains are those grown on mountain slopes.
Robusta was discovered relatively late, in the 19th century. It has a much higher caffeine content than Arabica (about 50 percent more), which is why it often occurs in a blend with other species to enhance their stimulant properties. Robusta also contains a higher concentration of chilogenic acids, which can cause stomach problems. Other coffee varieties worth paying attention to are Liberica or the most expensive coffee in the world – Kopi Luwak. Green coffee deserves special attention. This is not a separate type of coffee. The whole phenomenon is that it is not subjected to the process of burning grain. During this process, the chlorogenic acid content is reduced, and it is he who is responsible for most of the beneficial health properties of coffee.
2. Nutritional Values Of Coffee
Coffee itself is a drink that contains virtually no calories. One cup (220 ml) provides: 4.40 Kcal, 0.59 g carbohydrates, 0.33g protein and 0g fat. Additives such as milk, syrups, sprinkles, chocolate, sugar and whipped cream make it a calorie bomb. An interesting fact: brewing time in a pressure espresso machine (the most common way of preparing coffee in cafes) also affects the caloric content of the drink. The longer the extraction time (above 30 seconds), the more caloric we get the final product.
Despite the fact that coffee practically does not provide energy, it contains numerous nutrients that make it classified as a healthy drink. Contains 900 various substances including but not limited to all known caffeine but also organic acids, essential oils, phenolic compounds (mainly the aforementioned chlorogenic acid) or vitamins. The exact composition depends on the source, type and method of preparation. Those substances that have given coffee a special place in the diet of cyclists. It is not just an excuse for meetings and breaks during cycling escapades, it has much more benefits. Here are some facts about coffee.
Caffeine improves endurance. Share on X
Caffeine is a substance that affects the central nervous system by directly affecting brain functions. It acts antagonistically, i.e. in contrast to adenosine A1 and A2 receptors. What does it mean? Adenosine is a neurotransmitter that has inhibitory effects on both the nervous and cardiovascular systems. After drinking a cup of coffee, caffeine attaches to the adenosine receptor and prevents adenosine from attaching. However, the combination of caffeine with the A1 receptor produces slightly different effects than its attachment to the A2 receptor. When caffeine binds to the A1 receptor, the release of neurotransmitters: acetylcholine, dopamine and noradrenaline, increases. It manifests itself in the stimulation of the body, acceleration of heart rate and dilatation of blood vessels. However, by connecting with the A2 receptor, it stimulates the transmission of nerve stimuli. The effects we feel every day are stimulation and an increase in our concentration and attention. There are many of studies confirming the positive effect of caffeine contained in coffee on increasing endurance during training. One of them was a study conducted in 2019 at Coventry University in the UK, which examined the impact of pre-workout coffee consumption. Participants covered a distance of 5 km on a stationary bike. Both men and women, the time taken to complete the task was shorter (on average 6 seconds for women, on average 9 seconds for men). In participants receiving placebo, the result remained the same as before the experiment.
3. Is Coffee Dehydrating?
There is a widespread belief that coffee has a dehydrating effect. This question cannot be answered unambiguously. The caffeine contained in coffee is diuretic. This means that in theory it can increase urine output. This statement should be divided into several aspects. The amount of urine output is primarily influenced by the dose and frequency of coffee intake. It is assumed that drinking a high dose of caffeine at a time (about 300-500 mg, i.e. from 3-6 cups of coffee) causes short-term stimulation of urine output among people not consuming caffeine a few days or weeks earlier. If we belong to coffee fans and consume it daily, tolerance to its diuretic effect develops. So regular coffee drinkers should not be afraid of dehydration because of this.
4. Coffee And Leaching Of Minerals
Those who give up coffee because of the risk of leaching valuable nutrients from the body can breathe a sigh of relief. Coffee does not flush out calcium or magnesium, on the contrary. One cup of coffee provides on average 7 mg of magnesium, and 1 espresso even up to 24 mg. These are not large values, but the amount of these components flushed out with urine should be taken into account. In a 24-hour view, they are in the order of a few milligrams. Sometimes, when drinking coffee due to increased diuresis even the ratio of magnesium supplied to excreted is greater. It is relatively similar with calcium. It is therefore unreasonable to believe that coffee was to leach minerals from the body. Much more attention should be paid to the effect of coffee and the absorption of iron. The biggest problem occurs in women, and in particular in training vegans or people who are at risk of deficiency in this element.
People at risk of iron deficiency should pay attention not to consume coffee with a meal rich in this element, because it inhibits its absorption from 24 to even 73 percent. They should still not be afraid of coffee between meals.
5. Coffee And Its Impact On Health
A comprehensive review from 2017 noted that there is evidence of a beneficial effect of coffee when it comes to reducing the incidence of many diseases, including endometrial, prostate, colorectal cancer, liver as well as cardiovascular diseases, type 2 diabetes, Parkinson’s disease, Alzheimer’s disease or depression. Chlorogenic acid is mainly responsible for these properties.
6. When And In What Quantities To Drink Coffee?
Fortunately, the belief that coffee is harmful goes into oblivion. However, as with everything, the dose makes the product poisonous. It is obvious that it will be unhealthy to consume coffee in liters. Scientists, however, consider a safe dose of 400-500 mg per day, i.e. from 3-5 cups of espresso.
As a curiosity it is worth adding that until 2004, consumption of high doses of caffeine was considered doping. Fortunately, today we can enjoy coffee before the training session. The optimal dose that will work for athletes is 2-3g per kilogram of body weight consumed one hour before physical activity. It is worth adding that the stimulating effect of coffee is an individual matter for everyone. It’s mainly about our genetic conditions. Some will not feel any benefits from its consumption, on the contrary – it will cause drowsiness and fatigue. These types of people are not recommended to drink coffee before a training session. I encourage everyone else to enjoy a double espresso before workout.
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