Yoga helps the heart perform its function in an easy way. But before we look at the heart, let’s look at blood first. Because it is the blood that is pumped around by the heart.
Blood is made up of plasma (a liquid) and three different types of blood cells that are floating in this liquid. Almost 92 percent of the plasma is water. The rest are enzymes, hormones, antibodies, nutrients, gases, salts, proteins and metabolites of various kinds. The three types of blood cells are: red and white blood cells and platelets.
The role of the blood components
- Plasma transports nutrients like glucose (used by each cell for energy), vitamins, cholesterol, amino acids, triglycerides and fatty acids to and from all cells in the body. Plasma also plays a role in healing wounds and stopping bleeding through clotting and in helping your body to defend itself against infections with the help of ‘antibodies’ that are in the plasma.
- White blood cells play the biggest role in defending your body against disease. These white blood cells don’t only use blood to circulate through your body but also your lymph fluid. The white blood cells identify pathogens; intruders that will make you sick, like viruses. White blood cells destroy these intruders and clean up what is left of them after destruction.
- Red blood cells are the ‘best known’ blood cells we have. Their job is to ‘pick up’ oxygen at your lungs ant to transport it to all your cells and take CO2 (carbon dioxide) from your cells back to your lungs.
- The platelets are the smallest components of blood. They travel close to the wall of the blood vessels. If you injure yourself and start bleeding the platelets react immediately and stick to the edges of the wound and to each other, creating a seal which stops the blood flowing out of your body.
Functions of Blood
- Transportation: the primary function of blood in transport of nutrients, glucose (made by your digestive system), oxygen, CO2 and other important materials to and from your cells. Next to bringing these important materials to your cells, it also acts as a ‘garbage man’, by collecting metabolic waste from the cells and take it to your kidneys for excretion. Hormones also use your blood as a mean of transportation from the endocrine glands they were created to the place they have to be (muscle cells, organs etcetera).
- Protection: as we seen above blood as the task to protect your body against disease and infections. Your white blood cells are ‘schooled’ to fight and kill germs and viruses want to or can damage your body. The platelets work hard to limit loss of blood loss in case of injury.
- Regulation: blood plays a role in regulating the processes that are going on in your body to maintain homeostasis: It oversees the temperature of the body and maintains it, it controls the pH balance (how ‘sour’ or alkaline your body is), it keeps an eye on the levels of water and salt required by each cell of the body and it controls the blood pressure.
The blood is pumped around by the heart via the circulatory system Your heart has roughly the size of a large fist and weighs 280 to 340 grams. The heart has four chambers: two upper chambers (the atria) and two lower chambers (the ventricles). The right and left side are separated by a strong ‘wall’ of muscles.
The heart pumps the blood through the body using two circuits: the pulmonary circuit and the systemic circuit. In the pulmonary circuit, deoxygenated blood leaves the right ventricle of the heart via the pulmonary artery and travels to the lungs, then returns as oxygenated blood to the left atrium of the heart via the pulmonary vein.
In the systemic circuit, oxygenated blood leaves the body via the left ventricle to the aorta, and from there enters the arteries and capillaries where it supplies the body’s tissues with oxygen. Deoxygenated blood returns via veins to the heart’s right atrium.
The heart has a ‘pacemaker’ which regulates the contractions, making it able to pump the blood around. When it is pumped around the blood pushes against the sides of the blood vessels. The strength of this pushing is your blood pressure. If this pressure is too high, it puts too much strain on your arteries and your heart, which can lead to heart attacks and strokes. When doctors measure your blood pressure they measure the highest pressure (systolic blood pressure) and the lowest pressure (diastolic blood pressure). This is the pressure on your arteries when your heart relaxes between beats.
Effects of yoga on the heart
Research shows that:
- Yoga lowers your blood pressure and by doing so it slows down the process of ageing
- Yoga lowers your heart rate
- Yoga improves circulation
- Yoga helps to lower heart disease risks
- Yoga lowers levels of harmful LDL cholesterol
- Through yoga you become more sensitive to insulin, which is important for controlling blood sugar.