BRISK WALKING AND SERUM-LIPID AND LIPOPROTEIN VARIABLES IN PREVIOUSLYSEDENTARY WOMEN - EFFECT OF 12 WEEKS OF REGULAR BRISK WALKING FOLLOWED BY 12 WEEKS OF DETRAINING

The purpose of this study was to examine the effectiveness of brisk wa lking as a means of improving endurance fitness and influencing serum lipid and lipoprotein variables in previously sedentary women. Walkers (n = 10, mean(s.e.m.) age 47.3(2.0) years) followed a programme of br isk walking (mean(s.e.m.) speed 1.76(0.03)m s(-1)) for 12 weeks, after which the training stimulus was withdrawn. Controls (n = 10, mean(s.e .m) age 41.6(1.2) years) maintained their habitual sedentary lifestyle throughout. Endurance fitness was determined using laboratory measure s of responses to treadmill walking. Serum lipid and lipoprotein varia bles were determined in venous blood (12-h fasted). Body fatness was a ssessed by anthropometry and dietary practice using the 7-day weighed food intake technique. Measurements were repeated after 12 and 24 week s. Brisk walking resulted in a decrease in heart rate and blood lactat e concentration during exercise, while detraining was accompanied by a reversal. of these changes. Changes in body mass and the ratio of cir cumferences at the waist and hip did not differ between groups but the sum of four skinfolds decreased with brisk walking and increased with detraining. High density lipoprotein (HDL) and HDL(2) cholesterol inc reased with walking and decreased with detraining but no between group changes (analysis of variance, P < 0.05) were found in other lipid an d lipoprotein variables. These findings suggest that regular brisk wal king can improve endurance fitness and increase HDL cholesterol concen tration in sedentary women.