Doberman is a fairly big dog and it does require regular exercises on a daily basis to stay healthy and active. It is advisable to provide them with at least 2 hours of exercise every day. This is because their food intake is on the heavier side and physical activities make help them burn the calories gained and stay fit. Not being able to exercise tends to make them obese, lethargic, and irritable. Take them out for a walk at least twice a day to ensure their physical activity.