Walking is arguably the most popular form of exercise. Brisk walking can be even more beneficial. Benefits are manifold, It stimulates cardiovascular fitness, reduces body weight, BMI, fat and resting diastolic blood pressure. It is better to walk on an empty stomach. It will burn double the fat and carbs than after breakfast.
Steady walking, fast enough to make your heart beat faster and breathing deeper is important. But ensure that you slow down if you are unable to speak. As far as the time is concerned, walk min 30-60 mins per day, 4-6 days a week. Brisk walking is an easy, natural and accessible form of aerobic exercise. Walking is sufficient stimulus to increase cardiovascular fitness, reduce body weight, BMI and body fat, and decrease resting diastolic blood pressure in previously sedentary but otherwise healthy individuals.
They also found that fat breakdown with respect to the carbohydrate breakdown was greater, and overall energy expenditure was more when exercise was performed before breakfast, compared to when they exercised after breakfast.