[Importance of physical activity for prevention of chronic diseases].

A lot of epidemiological studies have shown that physical activity can prevent the development of chronic diseases such as obesity, diabetes, osteoporosis, cardiovascular diseases and cancer Physical activity can be classified by rate of energy expenditure: light intensity 1-3 METs, moderate 3-6 MET's, vigorous 6-9 MET's, very vigorous >9 MET's. Although it is evident that an active lifestyle has many health benefits and sedentary habits are associated with an increased risk of chronic diseases, the debate still continues as to how much, what type, how often, at what intensity physical activity should be performed to have a positive effect on the health. Reduction of cardiovascular risk is observed already with a moderate intensity physical activity (3-6METs); whilst to improve physical fitness training must be more vigorous (6-9 METs). In conclusion good goals are achieved when moderate levels of physical activity are performed on a regular basis (at least 3- 5 days a week for 30 minutes). But to reach also countable results on body weight control the frequency should be 5-7 days a week for 60 minutes.