I came across this article the other day:
Don’t worry if you can’t be bothered to plough through the detail of it, the two main points to bear in mind are the following:
“…athletes have in fact an increased total mass of red blood cells and hemoglobin in circulation…”
“…these adjustments cause a decrease in the average age of the population of circulating red blood cells in trained athletes. These younger red cells are characterized by improved oxygen release and deformability, both of which also improve tissue oxygen supply during exercise.”
Essentially our blood contains red blood cells, and it is these cells that carry oxygen and other nutrients to our muscles and organs. People who are physically fit have a greater concentration of red blood cells in their blood, and these tend to be younger which means they are better at carrying oxygen. This is one of the main characteristics of ‘fitness’.
Our muscles require oxygen to keep moving. The heart pumps the blood round our bodies and the red blood cells in the blood deliver the oxygen. When we exercise our muscles require more oxygen, so the heart speeds up to keep up with the increased demand. The heart, however, can only go so fast, and when it reaches its maximum capacity we are literally incapable of increasing or maintaining that level of exercise. If you increase your heart rate through exercise regularly the red blood cells become more concentrated. They also have a shorter life span so that those red blood cells in the blood are younger and more efficient at carrying the oxygen, so each pump of the heart delivers more oxygen. This has two results. Firstly we can exercise at higher and higher levels. Secondly our resting heart rate becomes lower and lower. This is because each pump of the heart delivers more oxygen so it has to beat less regularly. Of course the converse is also true. If we are regularly pushing our heart rate up without any related physical activity then each pump of the heart is delivering too much oxygen, so the red blood cells will space out and their life span will increase and consequently they will carry less oxygen. It is the reverse of getting fit; it is a way of actively becoming unfit.
So how do you get your heart rate up without exercising? Stress of course will do this (adrenaline increases heart rate) but another very common way of doing this is to take drugs that increase our heart rate. Alcohol can slow the heart rate down while we are drinking it, but it sends it through the roof when the alcohol wears off. This is yet more proof of the physiological effect of drinking; that the stimulants released by the brain to counter the depressive effects of the alcohol remain after the alcohol has been processed (for further detail on this point see Chapter 2 of Alcohol Explained which you can read here). Generally speaking, depressants will slow down heart rate while stimulants will increase it. So during the drinking session the heart rate may increase a bit but won’t be greatly accelerated, but when you wake up at four in the morning your heart will be going at such a rate that it will feel like it is about to burst out of your chest Alien style, and that increased heart rate will follow you around for the following 24 – 48 hours until the stimulants are finally dispersed. That is a physical manifestation of the stimulants remaining after the alcohol has largely dissipated.
In this way drinking regularly actually erodes our fitness, and this is to say nothing of the general lethargy drinking causes which is, in itself, a bar to exercise. And of course if you are actually hungover you are not going to manage that training session, and if you do force yourself to do it, it is going to be that much more difficult and that much less intense. Also, if one of the goals of your fitness routine is weight loss then you also need to then factor in the very clear link between drinking and obesity (see Chapter 10 of Alcohol Explained).
People often view drinking and its effect on health as a hit or miss affair. If your liver doesn’t conk out, or if you don’t have a crushing heart attack, or a killer stroke, you get away with it scot-free. But this isn’t the case. Every drink you drink erodes your fitness. A lack of fitness doesn’t just impact your life span; it also impacts your quality of life. Physical wellbeing is very closely related to mental resilience. It is also worth bearing in mind that this is just one aspect of the health effects of drinking of drinking, it doesn’t even factor in the effects of the sleep deprivation, the constant poisoning, the increased blood pressure and the effects of the alcohol related nutritional deficiencies (the first and last of these are dealt with in more detail in Chapters 6 and Chapter 10 respectively of Alcohol Explained).