In modern industrialized societies, the tasks of living require little physical movement. We sit in cars, in front of computers and TVs, and at desks at work and in class. The mind and body require movement, however, so incorporating some form of physical activity into one's life is necessary for health. From a health perspective, physical activity is defined as Choose...high intensity exerciseexercising at least one hour a day in a gymany activity involving movementincreasing body strength . The benefits of physical activity include a reduced risk of heart and other diseases, lessening stress, fostering other healthy behaviors, and taking time for oneself. Whereas Choose...focused awarenessfitnessexercisetraining effect can mean being in tip-top shape, it more generally includes having adequate strength and endurance to accomplish the tasks of living without undue fatigue and having reasonable joint flexibility. Working out to increase the amount of oxygen the body can process is Choose...strength trainingaerobic trainingtraining effectfitness ; whereas working out to increase muscle size and strength is Choose...strength trainingaerobic trainingtraining effectfitness . Obtaining optimal heart and breathing capacity requires raising the exercise- heart rate into the Choose...cardiovascular thresholdfitness requirementadrenalin capacitytraining effect, which is between 60 and 80 percent of maximum heart rate. Taking drugs like steroids and ephedra to increase body size, shape, strength and overall performance is a dangerous strategy. Short term enhancements often come with long term harm to the body. Movement and flexibility can produce a wide array of pleasures. To get the benefits of physical activity, individuals must choose activities that they enjoy doing and that fit into their schedules. Otherwise, they will not do them. Tremendous health benefits accrue simply from walking on a schedule of Choose...every day for at least 90 minutes each timetwice a week for one hour each timefour times a week for 20-30 minutes each timefive-six times a week for 75 minutes each time. Whereas regular physical activity is beneficial, too much of it can be harmful. Major drawbacks of excessive activity include Choose...overuse syndromesoverdose injuriesorthopedic restructuringoligomenorrhea such as muscle strains. Another drawback is psychological burn out. Both the body and mind require regular periods of rest to rejuvenate.