What are your goals? To lose weight? Put on muscle? In order to lose weight you need to work that heart harder. How many times a week are you walking? Would you say it is difficult (could you have a conversation with someone when walking? If yes, then you are not getting your heart rate up enough). Start a jog, light and see how you feel. You should do this for 45 minutes at least three times a week. After work outs you should eat. Carbs are great (whole wheat breads and grains are preferred), protein is also important. In order to be healthy you need a well balanced diet and to exercise on a regular basis. This site will help guide you on healthy way of eating.