Running is to sport as playing the piano is to music. It is an essential building block of many sporting activities, from football to cricket. Even for sports that don’t involve running directly – such as skiing or ice-hockey – running is often an important part of the athletes’ training programmes. This is partly because running is cheap, and requires no special skills, equipment, or organisation with team-mates. But it is also because running is an especially efficient way to increase fitness. Very few other sports – perhaps only swimming, rowing and cross country skiing – have such clear benefits in terms of all-round fitness.
What is fitness? How is it different from health?
Health means freedom from illness or injury, enabling a person to live normally and in comfort. Fitness means the ability to expend a lot of energy efficiently.
Fitness can be measured in many different dimensions. There are people who can lift huge weights efficiently, but could not comfortably run a mile. Weightlifters can generate huge bursts of energy for a short period of time, using their upper body. By contrast, there are marathon runners who would have the greatest difficulty performing simple gymnastics on parallel bars because they lack upper body strength, but who can propel their body around a 26.2-mile course with great efficiency. Both the weightlifter and the marathon runner are fit, in that they can expend energy efficiently, but they are fit in different ways.
Cardiovascular fitness means the ability of your body to absorb oxygen and transfer it through the blood supply to the muscles. The efficiency of your heart and lungs and health of your arteries are an important determinant of cardiovascular fitness. It is especially important for sports that require energy to be expended over a prolonged period of time, in which the fuel and oxygen needed to generate motion are not all stored in the muscles that do the work.
Fitness tests are generally aimed at measuring your cardiovascular fitness. But the fitness levels observed in a test depend both on your underlying cardiovascular fitness, and on the ability of particular muscle groups to translate energy efficiently in the activity used in the test – for example, your chest muscles to do press ups, or your legs when you run. This means that a trained runner will generally perform better in a fitness test on a treadmill than in a fitness test on an exercise bike.
How does running make you fit?
All fitness is acquired through a process of physical stress and recovery.
When you exercise, your body is required to do things that it does not normally do when you are resting. For example, when you run, your heart beats faster, your muscles work harder, and your metabolic system burns more fuel to transfer energy. When you stop the exercise, your body recovers and adapts to make it easier to do this in future. It is important to remember that your body’s adaptation occurs when you are recovering, not while you are actually undertaking the effort. This is why rest is one of the most important components of any training programme.
As well as increasing your fitness, running improves your health.
In the 2002 edition of this book, I said that the best medical advice is that you should exercise for 30 minutes a day for three to four days a week. Today, scientists say that people should aim for five or six days a week. This exercise should raise your heart rate to above 100 beats a minute, or to about 50-75% of your maximum heart rate (see Chapter 10 for a discussion about heart rates and exercise). Running regularly will increase your life expectancy and improve your quality of life.
Health benefits of running
Running has been shown to have the following health benefits:
- lower levels of and obesity;
- lower risk of heart disease and stroke;
- stronger bones, reducing the risk of osteoporosis, osteoarthritis and other bone deficiencies;
- reduced risk of diseases such as cancer and diabetes;
- improved immune system;
- stronger muscles, and less risk of degradation of joints;
- reduced risk of back pain;
- reduced incidence of depression and anxiety;
- increased coordination and mobility, especially in older adults.
Physical exercise is recognised by the UK National Health Service as a major contributor to good health and an important focus for health promotion. It is increasingly seen by the medical profession as one of the most cost‑effective ways to improve the health status of the population.
You may have been surprised by the suggestion that running can reduce the risk of damage to joints, since non-runners often claim that the opposite is true. Moreover, as your couch-potato friends probably point out to you, the legendary Jim Fixx, who kicked off the 1970s jogging craze in the US, died of a heart attack while out running. So what are the health risks associated with running?
The long-term impact on joints of running has not been especially well researched. Such evidence as there is suggests that people who have run consistently over many years have a lower risk in later life of joint problems such as arthritis than their sedentary counterparts.
However, running is more likely to put stress on your joints than swimming, cycling or skiing, because of the repeated impact of hitting the ground. These risks can be reduced by using good quality and appropriate running shoes (see Chapter 3), running on softer surfaces such as grass or trails when possible, and by starting running slowly.
As for the heart, the evidence is unambiguous: runners are less likely than non-runners to suffer from heart disease. Admittedly, if a runner is going to have a heart attack (e.g. because of an inherited predisposition to heart disease) then it more likely to happen while they are running than at other times of day, since this is when their heart is under most stress. It is true that Jim Fixx died of heart disease at the relatively young age of 51. But before he began jogging, he had been a heavy smoker, and he had very high blood cholesterol. Jim Fixx survived longer than his father, who died from a heart attack at the age of 43; and the likelihood is that regular exercise lengthened Jim Fixx’s life.