Fit News; Cardio and Nutrition

By JOHN FAUBER

Aerobic exercise shaves off years and risk of disease

A person who stays aerobically fit throughout middle age and beyond can delay the biological effects of aging by up to 12 years, according to a new analysis.

Aerobic fitness as measured by the body’s ability to use oxygen steadily declines during middle age.

One way to measure aerobic fitness is with the formula, milliliters of oxygen per kilogram of body weight per minute.

Aerobic power normally drops about 5 ml/(kg.min) every decade between the ages of 20 and 60.

For example, a typical sedentary man will have maximal aerobic power of about 25 ml/(kg.min) at age 60, about half of what he had at age 20.

When aerobic power drops below 18 ml/(kg.min) in men and 15 in women, moderate exertion can cause severe fatigue.

But high-intensity aerobic exercise such as running or cross- country skiing done over a long period of time can boost aerobic power by 25%, or a gain of 6 mi/(kg.min), which is equivalent to 10 to 12 biological years.

Maintaining maximal oxygen intake increases the likelihood a healthy elderly person will retain functional independence, wrote author R.J. Shephard of the University of Toronto.

“The progressive deterioration of aerobic fitness observed in middle-aged adults appears to continue unabated during the retirement years,” Shephard wrote. “A regular exercise program can slow or reverse the loss of aerobic fitness, reducing the individual’s biological age and prolonging independence.”

He noted that aerobic exercise reduces the risk of serious diseases, improves recovery from injury and illness and reduces the risk of falls.

The article was published in the British Journal of Sports Medicine.

Green tea may fight apnea effects, at least in rats

Anti-oxidants in green tea may help reduce cognitive deficits that result from sleep apnea, according to a study in rats.

For the study, the rats were intermittently deprived of oxygen in a manner similar to what occurs with sleep apnea in people.

The oxygen deprivation took place over 12-hour night cycles, which were designed to mimic the reduced oxygen levels experienced by people with sleep apnea.

One group of rats was given water containing green tea polyphenols and the other group got plain water.

The rats that got the green tea compounds performed significantly better on a water maze in which they had to memorize the location of a hidden platform.

The researchers noted that other animal research has showed that green tea polyphenols can help protect the brain against Alzheimer’s and Parkinson’s diseases.

People with sleep apnea tend to have higher levels of oxidative stress and changes in brain tissue involved in learning and memory.

Green tea polyphenols have anti-oxidant properties. Observational research suggests they may reduce the risk of developing a variety of diseases.

The researchers said consuming green tea polyphenols could be an interventional strategy for people with sleep apnea.

The study was published in the American Journal of Respiratory and Critical Care Medicine.

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