The purpose of this study was to examine the influence of brisk walking on endurance fitness and the amount and distribution of body fat in previously sedentary women. Twenty eight women [mean age (SEM): 44.9 (1.5) years] followed the walking programme for 1 year, whilst 16 acted as controls [age 44.4 (2.3) years]. Changes in endurance fitness were evaluated by measuring the oxygen uptake ( [(V)\dot]O₂\dot VO_2 ) at a reference blood lactate concentration of 2 mmol · 1^–1 . Two 1.61-km field tests of walking were completed, one at maximal speed and one at a [(V)\dot]O₂\dot VO_2 at 2 mmol·1^–1. In addition, brisk walking reduced heart rate and blood lactate concentration during stepping as well as during standard, submaximal treadmill walking. It did not modify either the amount or the distribution of body fat, despite an unchanged energy intake.