The cardiovascular system (the heart and blood vessels) responds to exercise like walking or running and habitual physical activities like housework or gardening. One only has to read the many stories of people who have come back from severe heart attacks and poor health to be marathon runners (like Ray Zahab!), century cyclists or triathletes to realize how much the body can change in response to consistent exercise.
Performing cardiovascular training has powerful effects on many systems in the body. From the lungs to the blood to the heart and right out to the muscles, the body adapts and improves itself to be able to handle the demands of exercise. The amazing thing is that not only does the body build itself up to handle exercise, but all the adaptations and changes help the body resist disease, and research has clearly shown that cardiovascular exercise reduces the incidence of diabetes, heart disease, cancers and many other diseases. The Youth Ambassadors have been running for hours every day across the Thar desert. On day 2 we measured Harshveer's heart rate as he ran. You can see the wide range of heart rates that we measured in the GPS / heart rate graphic below.
The heart contracts in a constant rhythm that may speed up or slow down depending on the need for blood (and oxygen) in the body. For example, if you start running, your leg muscles will need more oxygen to do the work of running. Therefore your heart will have to pump more oxygen-carrying blood to those working muscles and will have to beat more rapidly in order to supply that blood.
Heart rate is the term used to describe the number of times that the heart beats in one minute and is measured in beats per minute (b/m). At rest, the normal heart rate of an adult can range from 40 b/m in a highly trained athlete to 70 b/m in a normal person. Recent research has shown that your resting heart rate is associated with your lifespan - so if you have a high resting heart rate you are more likely to be affected by a chronic disease and have a shorter life. People with low resting heart rates have healthy cardiovascular systems, and lower nervous system stress, and are more likely to live longer. Check out your resting heart rate first thing in the morning when you wake up, or even when you are sitting relaxing.
Increasing physical activity is a key factor for helping to reduce the rick of non-communicable diseases like type 2 diabetes, obesity and cancer. Our bodies are designed to move, and even as little as 10 minutes of physical activity and exercise can burn a significant number of calories if you add that to your life on a daily basis.
The key message that I took away from my time here is how willing children here in India are to do physical activity if they have the right information and help to get started. That is the challenge that I'll pose to everyone who is following the expedition online. How can you increase your physical activity during your day? If you have ideas send them to us on the Q&A tab or via twitter @GOi2P.