1. The purpose of this study was to examine the influence of brisk walking on serum lipoprotein variables. 2. Seventy-two apparently healthy but physically inactive men (aged 42–59 years) were recruited. These men were normotensive non-smokers without a history of dyslipidaemia. Subjects were randomly allocated on a 2 to 1 basis into either a walking group ( n = 48) or a control group ( n = 24). Walkers followed a self-monitored programme of brisk walking for 1 year, whereas control subjects maintained their habitual lifestyle. 3. Treadmill walking tests were conducted to examine changes in fitness. Concentrations of serum lipids and lipoproteins were determined in fasting subjects. The amount of body fat was measured by body density. Circumferences at the waist and hip and skinfold thicknesses were used to determine the distribution of body fat. Dietary intakes were assessed by weighed food inventories. 4. Seven subjects (six walkers and one control subject) dropped out during the study. Walkers did an average of 28 (SEM 1.4; n = 42) min of brisk walking/day. This improved endurance fitness but did not influence serum concentrations of total cholesterol, high-density lipoprotein cholesterol, triacylglycerol, apolipoprotein A-1, apolipoprotein B or lipoprotein (a). Neither body mass nor the amount of body fat changed, relative to control subjects. 5. These data suggest that brisk walking does not modify lipoprotein metabolism in normolipidaemic middle-aged men.
1. In a previous study of the effects of methandienone (Dianabol) on men undergoing athletic training, strength and performance increased, but not significantly more when the subjects were taking the drug than when they were taking placebo. The subjects did, however, gain more weight on the drug, with increases in total body potassium and muscle dimensions. It remained an open question whether the muscles had gained normal tissue or intracellular fluid. 2. In an attempt to distinguish between these possibilities the trial has been repeated, using as subjects seven male weight-lifters in regular training, and including measurements of total body nitrogen. As before, a dose of 100 mg of methandienone/day was given alternately with the placebo in a double-blind crossover experiment. The treatment periods lasted 6 weeks and were separated by an interval of 6 weeks. Body weight, potassium and nitrogen, muscle size, and leg performance and strength increased significantly during training on the drug, but not during the placebo period. 3. The finding of increased body nitrogen suggested that the weight gain was not only intracellular fluid. The increases in body potassium (436 ± sem 41 mmol) and nitrogen (255 ± 69 g) were too large in proportion to the weight gain (2.3 ± 0.4 kg) for this to be attributed to gain of normal muscle or other lean tissue, and imply gain of nitrogen-rich, phosphate-poor substance. Although this action of methandienone might be described as anabolic, the weight gain produced is not normal muscle.