According to a new study, fitness decline speeds up after age 45 in both men and women. However, maintaining a healthy weight and exercising regularly helps.
Andrew Jackson, PED, from the University of Houston and colleagues write in the Oct. 26 issue of Archives of Internal Medicine, "The U.S. population is aging and is becoming more obese and sedentary. It is well documented that the cardiorespiratory fitness of men and women declines with age and that body composition and habitual physical activity are related to cardiorespiratory fitness."
They add that low fitness levels increase the risk of developing serious diseases and hamper the ability of older adults to function properly.
The stud comprised of 3,429 women and 16,889 men aged 20-96 who took part in the Aerobics Center Longitudinal Study between 1974 and 2006. Most of the participants where white, well educated, came from middle- to upper-socioeconomic backgrounds, and have access to health care.
The participants finished between 2-33 health examinations and had treadmill exercises to evaluate cardiorespiratory fitness.
The results indicated that though fitness levels deteriorate overtime, cardiorespiratory fitness declined faster after age 45, and it was worse in men than in women, the researchers say.
Moreover, the results also indicated that being active, keeping a normal BMI, and not smoking were associated with substantially higher levels of cardiorespiratory fitness during the adult life span studied," the researchers say. "Being inactive and having a high body mass index were associated with a lower age at which an individual could be expected to reach threshold cardiorespiratory fitness levels associated with substantially higher health risks."
Our body mass index is a widely used tool to measure a person’s fitness and is calculated using a person’s height and weight. An individual with a BMI of 29.9 is considered overweight and a person with a BMI of 30 and higher is considered obese.
Because of the increasing rates of obesity and the low levels of physical activity of the general population, the researchers say that their findings suggest that more men and women will reach the fitness level that is designated by the Social Security Administration as representing disability at a younger age.
According to the researchers, "These data indicate the need for physicians to recommend to their patients the necessity to maintain their weight, engage in regular aerobic exercise, and abstain from smoking."
They also that, "The finding that BMI and a habitual level of physical activity are important determinants (of cardiorespiratory fitness) raises a lifestyle concern for the older adult population."