The study was conducted by researchers, who invited 106 healthy but sedentary civil servants between the ages of 40 and 60 to take part in an exercise programme for 12 weeks.
Around 44 people were randomly assigned to 30 minutes of brisk walking on five days of the week.
A further 42 were given the same programme, but for three days of the week. And the remainder were not asked to change their current lifestyle.
Pedometers were used to help participants monitor their walking and every participant recorded how long they walked for.
Blood pressure, blood cholesterol, weight, hip and waist girth, and overall fitness (functional capacity) were all measured at the start and finish of the 12 week study. Most people lasted the course.
The researchers noted that systolic blood pressure and waist and hip girth fell significantly in both groups of walkers, as well as an increase in overall fitness in these groups.
Falls of a few mm in blood pressure and shrinkage of a few centimetres in hip and waist circumference are enough to make a difference to an individual's risk of dying from a cardiovascular disease.
The study is published in the Journal of Epidemiology and Community Health.