Improving the body's ability to process and deliver oxygen may improve stamina, not only in sports but also in every day life, doing any activity. To reach this goal, you need to strengthen and condition your heart because it is the organ that pumps oxygen-rich blood to the rest of your body. Like any muscle, the heart can grow stronger and more efficient by progressive demands in oxygen.
The aim is to develop bigger and stronger muscle units so that you can transport oxygen throughout the body with less effort and use more stored fat as energy. Increased oxygen consumption promotes overall health and increases metabolism resulting in burning extra fat stores. However, a mild activity can often just do the trick; it is not necessary to work up a heavy sweat.
Recent research results could hardly be clearer, when the subject of walking is brought up in the realm of exercise. Taking a walk is one of the best ways to take charge of your health. A study in the Journal of the American Medical Association showed that walking briskly for half an hour just six times a month cut the risk of premature death in men and women by 44 percent. Another study in the New England Journal of Medicine reported that men 61 to 81 years old sharply reduced their risk of death from all causes, including cancer and heart disease, by walking two miles a day. Other research has shown similar results for women.
Besides the well-documented health benefits, the beauty of walking is you can go at your own pace. If you are new to exercise or recovering from injury or childbirth, you can aim to walk for 20 to 45 minutes four or five days a week at the good fitness walking speed of three miles an hour. When (and if) you want to power up, you can take longer walks and work up to walking each mile in 15 minutes or less.
Once you are ready to hit the road (or the trail, track, treadmill or mall), how do you make the most of your walking workout? Here are a few tips and tricks:

Warm Up First, Then Stretch. Start by walking for just seven to 10 minutes (wear a watch) and then do a few gentle stretches. Your muscles will stretch better if you have warmed them up first. Ask a fitness professional which stretches are best for you.
Get Used To Walking. When you first start to walk, just walk. Take your time and get used to doing it again. Once your body has gotten used to the exercise it is time to improve and expand.
Take Short, Quick Steps. By taking short, quick steps, rather than long strides, you will work your glute muscles (in your buttocks) as you log miles.
Keep Your Head Up. Look about 10 feet ahead of you. Imagine you are wearing a baseball cap and have to look up just enough to see the road. This keeps your neck aligned properly.
Practice the Heel-Toe Roll. Push off from your heel, roll through the outside of the foot, then push through the big toe. Think of the big toe as the go button and push off with propulsion. Keep the other toes relaxed. (This takes practice.)
Smile and Have Fun. Learning these techniques takes time and concentration. Be patient and enjoy your workout. Dress comfortably, find a partner or wear a headset and listen to music you love and, if you're walking outdoors, vary your route.
Squeeze Your Glutes. Imagine squeezing and lifting your glutes up and back, as if you were holding a bill between them! This will strengthen your low-back muscles. Developing the ability to maintain this deep contraction throughout your walk will take a while.
Feel a hand on your back. Imagine as you walk that somebody has a gentle but pushing hand on the small of your back - mentally you feel as if you have a silent partner.
Pump Your Arms. Imagine you are holding the rubber grips of ski poles in your hands. Stand straight, drop your shoulders, squeeze your shoulder blades behind you and push back your elbows with each step. Keep your arm movements smooth and strong.
Zip Up Your Abs. During your walk, imagine you are zipping up a tight pair of jeans. Stand tall and pull your abdominal muscles up and in. You can practice this even when you are not walking.
Keep Your Chest Up, Shoulders Back. Use your walk as an opportunity to practice perfect posture. Imagine someone dumped ice down your back. That is the feeling you want to have as you hold your chest up and shoulders back.
Practice Mental Fitness. Do not replay the problems of the day while you walk. Try to maintain a state of relaxed awareness by paying attention to your breathing and noticing how your body feels. Visualize yourself getting healthier, stronger and leaner.
Consistency is probably the most important part of your walking workout. The more committed you are to walking all or most days of the week, the healthier you will be. Remember that short walks are better than none at all. The path to good health, like life, is a journey. All you have to do is take the first step.