"Use it and it works; don't use it and it's useless": Reshaping the physical and mental abilities of middle-aged and elderly people.

If people were to discover the fountain of youth, the famous saying inscribed upon it would be, "Use it or lose it." The immaturity of the heart, lungs, joints, and other functional disorders are usually the result of underuse or misuse-not overuse. Robert N. Butler, former director of the National Institute on Aging, says that exercise has not yet been proven to extend lifespan, but if it could be packaged into a pill, "it would be the only prescription, the most widely used and beneficial medicine." Exercise improves cardiopulmonary function, strengthens bones, and prevents cardiovascular disease. Exercise can also delay or reverse many age-related changes or declines in strength and motor abilities. While aging weakens strength, muscular endurance, speed, capacity, and gross motor skills, exercise can increase them. Balance and fine motor skills may weaken or remain unchanged with age, but exercise can maintain their stability or improve them through training. Reaction time increases with age, but can be maintained without significant change through consistent exercise and practice. According to a study by the U.S. Center for Gerontology on extensively trained athletes aged 55 or older-many of whom ran or briskly walked 55–60 kilometers per week-most had oxygen consumption similar to that of healthy 25-year-old athletes. Researchers noted that these individuals also had better overall health, fewer limitations in daily activities, lower blood pressure, less obesity, lighter weight, less diabetes, better cholesterol levels, greater agility and strength, higher confidence and self-esteem, and less depression than sedentary individuals of the same age. The adage "use it or lose it" also applies to intelligence and mood. The cognitive decline that occurs with age often stems from the expectation that intelligence will also decline. Studies show that after age 60, those who led active middle-aged lives maintained or improved intelligence. Those who led passive lives showed significant cognitive decline. For example, two studies of men and women listed in Who's Who in America in the 1950s and 1960s showed that successful individuals in both sexes lived an average of 29% longer than their peer groups. While this only demonstrates that some traits associated with achievement are also related to longevity (like being made of high-quality material). However, it's equally possible that the pressures of striving and competition can extend, rather than shorten, their lives. The principle of "use it or lose it" also applies to sex and social activities. Growing old doesn't diminish your ability to enjoy sex; many reported declines in sexual activity are attributed to alcohol, drugs, and negative attitudes such as, "What do you expect at your age?" While aging may prolong the time to sexual arousal and orgasm, a growing number of reports claim that many older adults derive satisfaction from their sex lives due to the deep emotional involvement during intercourse and harmonious relationships with their spouses. Maintaining a close social network throughout life is also crucial. Those at any age who fall asleep in front of the television and rarely speak to family or friends may have their life prematurely extinguished. Benjamin Franklin and the other 13 people who signed the Declaration of Independence at age 55 lived to their 80s, exceeding the average lifespan of that time by about 30 years. They all led active lives; Bertrand Russell, who organized calls for international peace, was still driving at 94; George Bernard Shaw wrote plays at 93; and Pablo Gassars gave a cello recital at 88. In modern times, the Vergabenbo people of Ecuador, the Hanzas of Pakistan, and the Caucasians of the former Soviet Union are renowned for their remarkably good health in old age. Although it is difficult to verify their actual ages, the inhabitants of these places appear to live longer than average. For example, studies of the Caucasians show that they eat small, healthy meals, exercise, work hard, maintain sexual activity, and live with family members in their later years. It is not unusual to find an 89-year-old shepherd, a 97-year-old vineyard worker, or a 101-year-old carpenter among them. Research on decades of aging shows that those who lead varied and complex lives-exercising, reading, socializing, learning, loving, playing, and helping others-generally live longer than their peers with monotonous lives.