Killer Stairs? Taking The Elevator Could Be Worse For Your Body

For years, scientists have been proclaiming the benefits of exercise. Studies showing that regular exercise benefits human health have exploded in number, examining many health problems ranging from cancer and diabetes to arthritis and pre-mature death. Now, a University of Missouri researcher has found direct evidence to support the claim of the Centers for Disease Control that a reduction in daily physical activity is an actual cause of many of the risk factors for chronic diseases, including diabetes and cardiovascular disease. The research team also found that it only takes about two weeks of reduced activity for individuals to start noticing the effects. “A low level of daily physical activity not only doesn’t help your current health status, it could be the reason you got sick in the first place,” said Frank Booth, professor of biomedical sciences in the MU College of Veterinary Medicine. “Our study looked at what happened when a group of individuals reduced their daily physical activity. Our findings indicated that if there is a lack of normal physical activity, a person greatly increases the chances of developing a chronic disease. Previously, we thought that not exercising just wasn’t healthy, but we didn’t think that a lack of activity could cause disease. That assumption was wrong.”

Booth and researchers at the University of Copenhagen conducted two different studies in Copenhagen. In the first study, participants were asked to reduce the amount of steps they took per day from 6,000 to 1,400 for three weeks. instead of walking or taking the stairs, participants were instructed to use motorized transportation, such as a car or elevator, in every situation possible. The second study asked participants who were more active, averaging 10,000 steps per day, to reduce their activity to 1,400 steps per day for two weeks.

The number of steps the average American adult takes per day is 7,473, although Americans who are inactive typically take about 2,100 steps each day. At the end of each study, participants were administered a glucose tolerance test or a fat tolerance test, or both. These tests measure how fast the body is able to clear glucose or fat from the blood stream. The researchers found that after two weeks of no exercise and very little activity, participants had much higher levels of glucose and fat and took a much longer time to clear the substances from their blood streams than before. The longer it takes the body to clear the blood stream of the substances, the higher the likelihood that a person will develop diabetes or other chronic diseases.

“We used to think that it is healthy to be physically active, but this study shows that it is dangerous to be inactive for just a couple of weeks,” said Bente Klarlund Pedersen, coauthor and lead investigator of the study and professor of internal medicine and director of Centre of Inflammation and Metabolism at the University of Copenhagen. “After 14 days of reduced stepping, subjects experienced accumulation of the dangerous abdominal fat, while also developing elevated blood-lipids, a sign of -prediabetes and cardiovascular disease. If you choose the passive mode of transport and abstain from exercise, than your risk of chronic disease is likely to increase markedly.”

“When the doctor says to go and exercise, they are not just telling patients to do that to improve their health; increasing daily stepping could actually reverse a cause of chronic disease,” Booth said. “When extra fats and sugars (glucose) don’t clear the bloodstream, they go where we don’t want them and cause problems for our bodies’ typical metabolic functions.”

The researchers also found that the total skeletal and muscle mass in the body decreased when activity decreased. Booth says that longer studies are needed to help answer more questions about the detrimental effects of long-term physical inactivity.

The study is being published in the Journal of the American Medical Association (JAMA) the week of March 18

Maintaining Aerobic Fitness Could Delay Biological Aging By Up To 12 Years, Study Shows

Maintaining aerobic fitness through middle age and beyond can delay biological ageing by up to 12 years and prolong independence during old age, concludes an analysis published ahead of print in the British Journal of Sports Medicine.

Aerobic exercise, such as jogging, improves the body’s oxygen consumption and its use in generating energy (metabolism). But maximal aerobic power starts to fall steadily from middle age, decreasing by around 5 ml/[kg.min] every decade. When it falls below aound18 ml in men and 15 ml in women, it becomes difficult to do very much at all without severe fatigue. In a typical sedentary man, the maximal aerobic power will have fallen to around 25 mil/[kg.min] by the age of 60, almost half of what it was at the age of 20.

But the evidence shows that regular aerobic exercise can slow or reverse the inexorable decline, even in later life. Research shows that relatively high intensity aerobic exercise over a relatively long period boosted maximal aerobic power by 25%, equivalent to a gain of 6 ml/ [kg.min], or 10 to 12 biological years. “There seems good evidence that the conservation of maximal oxygen intake increases the likelihood that the healthy elderly person will retain functional independence,” says the author. The other positive spin-offs of aerobic exercise are reduced risks of serious disease, faster recovery after injury or illness, and reduced risks of falls because of the maintenance of muscle power, balance, and coordination.