You do need cardiorespiratory fitness
Effects of Different Doses of Physical Activity on Cardiorespiratory Fitness among Sedentary, Overweight or Obese Postmenopausal Women with Elevated Blood Pressure.
Proactol and a sensible weight loss plan- Summary: Even a small amount of exercise—around 72 minutes a week—can have a significant impact on the level of C.R.F. or exercise ability of overweight or obese postmenopausal women. Why it’s important: According to the study authors, “Low levels of cardiorespiratory fitness are associated with high risk of cardiovascular disease (CVD) and all-cause mortality, and improvements in fitness are associated with reduced mortality risk.” Put simply, the less fit you are in terms of your heart and lung activity, the higher your risk of heart disease and death. Although it has been known that exercise can have a positive impact on such fitness, this study provides an important contribution in understanding how much exercise is required to have any kind of effect. What’s already known: Many previous studies have shown that exercise can produce a positive effect on cardiorespiratory fitness (or the ability of the heart and lungs to supply oxygen to the muscles during exercise). Some have even analyzed the data from other studies to try to predict exactly how exercise affects such fitness. However, none of these previous studies gathered specific data on levels of exercise, especially taking into account the National Institutes of Health’s (NIH) recommendation that people exercise at least 30 minutes a day. How this study was done: A study group of 464 women aged between 47 and 75 years and considered “sedentary”— less than 20 minutes fewer than three days a week and taking less than 8,000 steps a day—were selected for the study. All of the women had a body mass index of between 25 and 43, which put them in the categories of overweight to obese, and had normal to high systolic blood pressure. That means the upper number in the blood pressure measurement was between 120 and 150 mm Hg. Women with histories of stroke, heart attack or other life-threatening conditions that would have prevented them from completing the exercise program were excluded. These women were randomly assigned to four groups: a control group who were asked not to change their normal amount of exercise, a group assigned to burn 4 kilocalories per kilogram per week (50 percent of the NIH-recommended amount of exercise for women of this age and weight range), a group assigned to burn 8 kilocalories per kilogram per week (the recommended amount), and a group assigned to burn 12 kilocalories per kilogram per week. The women in the groups assigned to an exercise program participated in three or four training sessions a week for six months. Exercise was conducted in a laboratory setting using exercise bicycles and treadmills and the women were monitored and supervised. Fitness was measured in terms of the amount of oxygen consumed and the amount of power they generated through their exercise. What was found: Women who did even a small amount of regular exercise showed improvement in the ability of their hearts to pump blood and the amount of oxygen they took in—both primary indicators of cardiorespiratory fitness. The improvement was statistically significant. Even the group that exercised only half as much as recommended by the NIH benefited. These women exercise about 72 minutes (72.2 min) per week. Waist size was also significantly smaller in all three exercise groups than the control group that did not change their activity level. “Perhaps the most striking finding of our study is that even activity at the 4-kcal/kg per week level [approximately 72 min/wk over about three days] was associated with a significant improvement in fitness compared with women in the nonexercise control group,” the authors led by Timothy Church, MD, MPH, PhD, of Pennington Biomedical Research Center at Louisiana State University in Baton Rouge, Louisiana, write. “This information can be used to support future recommendations and should be encouraging to sedentary adults who find it difficult to find the time for 150 minutes of activity per week, let alone 60 minutes per day.” The bottom line: Even a little bit of exercise can have an important effect on one’s health and chances for a longer, healthier life. However, the benefits grow as you increase the amount of exercise you do. Put more simply by I Min Lee, M.B.B.S., Sc.D, of the Harvard School of Public Health in an accompanying editorial: “Even a little is good; more may be better!”
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