There are many theories about ageing. Calendar age is different from biological age. We know young oldmen and old youngsters. Ageing is not an illness, it starts to be present in the period of maturity which is sometime after the 60th year of life. Changes associated with ageing do not have to occur to everyone in the same way nor in the same time. As every one of us is specific, has different abilities and capabilities, even in the process of ageing there are huge differences between individuals. And, of course, it considerably affects their abilities to live an active and contented life.

From the functional point of view is the clearest sign of ageing a decline of physical power and of capacity. Functional changes of sight, hearing occur, mobility and memory worsen. These changes we can simplify to one word—a decline. Hypodermis, muscle tissues and tissues of internal organs and bones decline. The total decline of tissues is, however, the most evident when it affects brain cells. Therefore many people complain about the fact that the older they are, the more they forget. Health of older people is mostly affected by heart and vessel diseases, oncological diseases, reduction of bones—osteoporosis and other diseases of the musculoskeletal system, rheumatism, metabolism disorders etc. Some people develop various psychological disorder. Injuries among older people with subsequent fractures are not rare.

No one can be protected from ageing, but it has been proven that people with optimistic nature take old age easy and they surely live more fully and pleasantly than pessimists of the same age if not longer. In older age it is important to pay attention to psychohygiene. Breaking all social ties leads to isolation, personality disintegration. It is essential to prepare ourselves for old age similarly to our thoughtful preparation for life profession. Third age can take even more than 20 or 30 years.