What is the ability of the heart and lungs to provide the body with enough oxygen during extended periods of physical activity?

You already know exercise is good for you. You probably think about the way it can boost your fitness, trim your waistline, strengthen you heart and even improve your mood. But did you know that exercise can also help keep your lungs healthy?

How Does Exercise Strengthen the Lungs?

When you are physically active, your heart and lungs work harder to supply the additional oxygen your muscles demand. Just like regular exercise makes your muscles stronger, it also makes your lungs and heart stronger. As your physical fitness improves, your body becomes more efficient at getting oxygen into the bloodstream and transporting it to the working muscles. That's one of the reasons that you are less likely to become short of breath during exercise over time.

Some types of exercise can also strengthen the muscles of the neck and chest, including the diaphragm and muscles between the ribs that work together to power inhaling and exhaling.

The Benefits of Exercise

Exercise has lots of benefits for everyone, whether you are young or old, slender or large, able-bodied or living with a chronic illness or disability. Physical activity can reduce your risk of serious illness, including heart disease, stroke, diabetes and some forms of cancer, including lung cancer. Being active can help you stay active, by strengthening bones, improving flexibility and agility, reducing weight gain and improving sleep. Regular exercise is good for your head too. It can reduce feelings of anxiety and depression, improve attention and memory, and reduce the risk of dementia, including Alzheimer's disease.

What Types of Exercise and How Much?

National guidelines recommend that all adults get 30 minutes of moderate physical activity five days a week. It doesn't have to be a formal exercise program to be beneficial. Some examples of moderate activity include walking briskly, recreational bicycling, gardening and vigorous housecleaning.  

Both aerobic activities and muscle-strengthening activities can benefit your lungs. Aerobic activities like walking, running or jumping rope give your heart and lungs the kind of workout they need to function efficiently. Muscle-strengthening activities like weight-lifting or Pilates build core strength, improving your posture, and toning your breathing muscles. Breathing exercises in particular can strengthen your diaphragm and train your body to breathe more deeply and more effectively.

Some Things to Keep in Mind

• Always talk to your doctor before you start or modify your exercise routine. This is especially important if you have an underlying health condition.
• Avoid exercising outdoors when pollution levels are high. When the air is bad, walk indoors in a shopping mall or gym or use an exercise machine. Limit the amount of time your child spends playing outdoors if the air quality is unhealthy.

Exercising with Lung Disease

People living with lung disease can and should get regular exercise for all the same reasons as everyone else. Your lungs and heart stay stronger, you are better able to perform the tasks of daily living and you feel better in mind and body. But if you already are dealing shortness of breath, it can be intimidating to think about increasing your physical activity. It is important to work with your healthcare team to make a fitness plan that works for you.

To learn more about staying active with lung disease, check out the links below:

• Pulmonary Rehabilitation
• Physical Activity and COPD
• Physical Activity and Lung Cancer
• Physical Activity and Pulmonary Fibrosis

While there are numerous methods for evaluating aerobic capacity, in most instances treadmill walking/running is appropriate for the majority of individuals. Normative data correlates time on the treadmill with aerobic fitness. V̇O2 is an index of the body’s efficiency at producing work. It is expressed in milliliters of oxygen consumed per minute, and adjusted for body weight in kilograms: ml/kg/min. There are many factors that can influence V̇O2max, e.g. heredity, training, age, gender, and body composition. Generally, V̇O2max declines with age (about 2% per year after age 30) and males typically have a greater oxygen consumption value than females. Nevertheless, the trend is that a higher V̇O2 max allows one to produce more energy, thereby performing more work. With this in mind, V̇O2 max is the "gold standard" measure of overall fitness.

Aerobic fitness is assessed by having the subject perform exercise at increased loads, for 12 to 15 minutes, while breathing into a mouthpiece which collects information on inspired and expired air. A treadmill, personal bike on a Computrainer, or a stationary bicycle are typically used. The test starts with an easy-moderate work load which is maintained for a 1-2 minutes. The load is increased gradually every 1-2 minutes until reaching the maximum level that the subject can tolerate and/or until physiological parameters such as heart rate, oxygen consumption, f... have hit a peak or plateau. This is done by increasing the cycling resistance or the speed and/or grade of the treadmill. The oxygen uptake, heart rate, speed and/or watts are measured at the ventilatory threshold and at maximal load, the latter would be the subject's V̇O2 max.

V̇O2 max values cannot be used in every day training, but follow-up V̇O2 tests can be used as a measure of progress. However, since heart rate, speed and/or power is typically measured during a V̇O2 max test, various heart rate, speed and/or power levels can be garnered from testing and then associated to appropriate training zones, which are then applied to everyday training. Other information such as V̇O2 economy (oxygen consumption values at a given heart rate or power output) can also be extracted from the data, compared to subsequent tests and against performance norms.

Training results in an increase in the efficiency of oxygen transport within the body. By lowering the resting heart rate (HR), and the HR at sub maximal loads, the heart pumps more blood with every heart beat. This, in addition to other physiological changes, increases the oxygen extraction capability. When an individual is tested before and after training while performing exercise at the same load, a lower HR is shown after training because more blood (thus, oxygen) is delivered in each heart beat. Such HR differences during exercise can be used to predict aerobic fitness.   The % of increase in V̇O2 max is dependent on many variables and differs considerably from individual to individual, ranging from 5-30%. In general, individuals who are the least fit see the largest changes and individuals who are highly fit see the smallest changes.

Significant amounts of research and public health data indicate that low aerobic fitness levels are correlated with an increased risk of premature death from many causes but in particular from cardiovascular disease. Accordingly, higher aerobic fitness levels are associated with numerous health benefits e.g. longer lifespan, better quality of life, reduced risks for stroke, heart disease, diabetes and cancer, improved mood and self-esteem, and improved sleep patterns. To improve or maintain cardiovascular health an individual must engage in cardiovascular exercise (run, walk, swim, bike, etc...) at least 3 times per week. Currently, however, public health data indicates that only 22-25% of Americans exercise regularly enough to achieve these positive health benefits.

V̇O2 max is also a predictor of performance, although its correlation to athletic success in endurance sports is only 30-40%, with other factors such as sustainable lactate threshold, motivation, training, etc... also playing a role. In general, however the higher a V̇O2 max the more potential for a successful performance in an aerobic endurance event.

What is the ability to the heart and lungs to deliver the oxygen the body needs for its daily tasks?

What is the ability of the heart and lungs to make you do physical activity for a long period of time?