Fisieke werksvermoe se verband met enkele serumlipied-ratio's by Suid-Afrikaanse dames en die invloed wat sigaretrook hierop het

Abstract

THE RELATIONSHIP BETWEEN PHYSICAL WORK CAPACITY AND SOME SERUM LIPID RATIOS IN SOUTH AFRICAN WOMEN AND THE INFLUENCE OF CIGARETTE SMOKING

In 1986 Brink stated that South Africa is known as the "graveyard" of the world, and it is indeed so that South Africa's death rates rank among the highest in the world. This is especially true of white and Asian populations, and coronary heart disease (CHO) has been identified as the main cause (Brink, 1986:13). Research , reported in 1996, indicated that the death rate for the South African population, due to heart-related diseases, was almost 85 000 for that year and that it is still increasing (Statistics South Africa, 1996: 143) Physical inactivity, hypertension, smoking and high total cholesterol concentration are contributors to the development of atherosclerosis and the increased risk of coronary heart disease (Byrne, 1991 :3). Several studies have already reported on the important role of physical fitness/physical work capacity, as a beneficial factor, with regard to the development of coronary heart disease (Blair, 1996:208; Eaton et al., 1995:342 & Bovens et al. , 1993:575). Women experience many changes during menopause (Glenville, 1997:11 ) and it is reported that physical exercise can improve their quality of life by preventing osteoporosis and increasing the cardiorespiratory fitness, thus reducing their risk of coronary heart disease (Haddock et al., 1998:893; Shangold, 1998:48). Firstly, the objective of this study was to determine the relationship between physical- work capacity and the total cholesterol/high-density lipoprotein-ratio (TC/HDL-ratio) and the low-density lipoprotein/high-density lipoprotein-ratio (LDUHDL-ratio) among South African women. Data were gathered from 357 women.

Due to the fact that the onset of menopause is usually between the ages of 48 and 52 years (McKinlay et al., 1992:103; Shangold, 1998:46) the women were divided into two groups, pre- and postmenopausal, (35-49 years and 50-64 years). Physical work capacity was expressed as sub-maximal power output (watt.kg-1 ) achieved during a progressive cycle ergometer test. Non-fasting blood samples were taken. Laboratory analyses to determine the total cholesterol (TC), low-density lipoprotein (LDL-C) and high-density lipoprotein (HDL-C) cholesterol concentrations were executed, as described by Vermaak et al. (1991 :368). The analyses of the data indicated no significant differences (ps≤0.05) between the two groups for both the ratios. Overall the women in both groups could be classified as having higher than normal lipid ratios, thus placing them at an increased risk of developing coronary heart disease (CHO). Secondly, the effect of smoking was examined on the above mentioned relations. Analyses of data indicated no significant differences (p s;0.05). It is concluded that the results found in this study were influenced by the small number of the population groups studied.