A workmate of mine is in his early 40s, and his kids who are in their 20s, thought he was mad for going for a two-day bike ride "at his age". Another friend is in her 50s and is starting a new career in the fitness industry as an instructor and manager, and is criticized for not wanting to slow down and take it easy.
We are living longer than our grandparents, but are we really living with vitality? Research indicates that the extra years we are gaining are being wasted. Only 12 percent of the people who die after the age of 65 can be described as being "fully functional" before their death, if we use the ability to carry out five basic daily tasks as an indicator of "functionality" — the ability to dress, walk, eat, go to the toilet, and bathe. In other words, 88 percent of people aged over 65 cannot carry out even these basic daily tasks. Could it be that there is a difference between living a long time and getting old?
No matter what your age or current physical state, you can improve the major symptoms of biological aging through increased levels of physical activity, and boost this if you also improve your diet.
There are 10 major categories for age that are accepted as being reversible through physical activity:
- Basal metabolic rate. The body's metabolic rate, which is the rate that it uses up energy for its normal biological functions, declines by 2 percent per decade after the age of 20.
- Lean body mass (muscle). On average, you will lose about 3kg of muscle each decade after the age of 20 and more after the age of 45.
- Strength. Older people get weaker because they are losing muscle mass, and because the nerves that activate muscles are dwindling in number and capacity.
- Body fat. It's ironic that as people get older they are satisfied if their body size and weight is the same as when they are younger. Their sedentary lifestyle and overeating of a nutritionally poor diet doubles the ratio of fat to muscle, so if they are losing 3kg of muscle a decade and they still weigh the same at age 65 as 20, then they are going to be fat. Obesity is implicated in many of the diseases of older people.
- Aerobic capacity. Your potential aerobic capacity, which is your body's ability to absorb oxygen and combine it with body fat to create energy, declines by 30 to 40 percent from the age of 20 to 65.
- Blood pressure. Blood pressure creeps up as the years roll by.
- Blood-sugar tolerance. The body's ability to maintain blood-glucose levels, which are important in providing short bursts of energy, declines with age, and is implicated in the development of adult-onset diabetes.
- Cholesterol/HDL ratio. There is "good", high-density, cholesterol (HDL) in the body, scrapes plaque off the walls of blood vessels, and protects the body against cardiovascular disease. There is also "bad", low-density, cholesterol (LDL) that gums up the cardio vascular system. As you age you get a higher amount of cholesterol and a higher ratio of LDL.
- Bone density. Calcium is lost from the bones with age, making the whole skeleton weaker, less dense, and more brittle. The Dairy Corporation has seized on this fact to sell dairy products as a way of preventing osteoporosis. Putting calcium inside your body will do little good if your body is not stimulated to increase the strength of bones, and the best way to do this is by gentle exercise.
- Body temperature regulation. As you age you lose the ability to maintain a constant internal temperature, and become more sensitive to cold weather.
All these changes are really negative adaptations to a poor lifestyle. If your lifestyle improves, you will improve your fitness and health.