The two significant aspects of weight loss are diet and exercise. Regular physical activity is as important as a well-balanced diet. The benefits of adequate exercise are not only limited to weight loss, but also in prevention of many health conditions and reduction of stress.
The basic principal of weight loss is to burn more calories than the amount you intake. Calorie restriction in your diet can only help partially, in achieving this. Performing any physical activity, requires energy which is released by burning of fat reserves in the body.
Cardiovascular exercises like running, swimming, and cycling, increase your heart rate and cause a spike in the metabolism that lasts for up to an hour after your workout session. A higher metabolism implies a faster rate of fat burn. On your exercise days, your basal metabolic rate stays higher than other days and consequently you burn extra fat, even while sleeping. A 45-60 minutes workout session at least thrice a week, along with a healthy diet, is adequate for getting a fitter and leaner body. Here is some more information about how much cardio to do.
As opposed to cardio exercises, weight training workouts help in building of lean muscle. More muscle mass leads to an increased basal metabolic rate and contributes to progressive weight loss.
Maintaining a fitness routine requires a lot of commitment and time devotion. However, the benefits of exercise are more profound and long term than you could possibly imagine. So, just put on your shoes and go for a walk and reap the fruits of your labor, for many years to come.