Diet and physical activity as determinants of nutritional status in elderly women

The purpose of the studies described in this thesis was to examine the relationship between physical activity, dietary intake and nutritional status in elderly women.Background of the study was a lack of knowledge about the existence of nutritionally unfavourable pathways associated to the age-associated decrease in physical activity, leading to either overweight or nutrient deficiencies.A physical activity questionnaire was adapted and validated for use in elderly people and applied to perform a cross-sectional study in independently living apparently healthy women aged 60 to 80 years. Comparison revealed a marked weight difference, body weight being substantially higher in sedentary elderly women compared to women with a high level of physical activity. In retrospect, analysis of both body weights and physical activities showed that the weight difference was already prevalent at the age of 25 whereas no differences could be detected in former levels of physical activity. It was suggested that the currently low level of physical activity was more a result rather than a cause of a high body weight. Using a battery of tests to assess physical fitness it was shown that flexibility and endurance were associated to level of physical activity. Data were confirmed in findings on subjective fitness. Measurement of energy expenditure at rest and during standardised activities revealed that energy costs of walking on a treadmill were markedly higher in elderly than in middle-aged women.Conclusions of the study were that women with a higher body weight might be more likely to reduce physical activity with ageing. An explanation is that the age-dependent increase of energy costs of moving around makes the performance of physical activity unpleasant, especially in women with a high body weight