In recent years, antioxidants have been touted as a secret to healthy living: The molecules bind to reactive oxygen compounds called “free radicals” that are known to damage the body’s tissues. The amount of oxidative damage increases with age, and according to one theory of aging it is a major cause of the body’s decline [The New York Times]. But a new study examined the effects of the antioxidant vitamins C and E when combined with an exercise regimen, and found a considerably more complicated story. The researchers found that free radicals may be beneficial in small doses, and may even help protect against diabetes. And mopping them up with antioxidants may do more harm than good [BBC News].
During a workout, the muscles metabolize glucose to create energy, but in the process some free radicals are released. The body has a natural defense mechanism to combat these free radicals, but many researchers had theorized that the body can’t catch all of the harmful compounds, which makes antioxidant supplements sound like a logical solution.
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Astronauts who live aboard the International Space Station for months are losing more muscle mass and strength than researchers thought, and NASA thinks there’s only one cure: a better workout. A new study that used MRI scans and biopsies to test astronauts’ muscles before and after a stay at the space station found that the volume of their calf muscles decreased by an average of 13 percent during six months in space…. [Lead researcher Scott] Trappe says that the magnitude of loss in muscle mass is akin to the difference between a 25-year-old and an 80-year-old [Scientific American]. Leg muscles are the most vulnerable to atrophy, researchers say, because on Earth they receive constant exercise just by supporting a person’s weight.
Space station residents currently exercise at least two hours each day to prevent their muscles and bones from wasting away in the weightless microgravity environment. The recent study showed a range of astronaut exercise regimens, including five hours per week spent on aerobics, and anywhere from three to six days per week spent on resistance training [SPACE.com]. However, the treadmill and exercise bike that astronauts use are mostly intended to maintain cardiovascular health, and are little help for muscle strength.
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A drug that mimics the effects of a compound found in red wine has been shown to prevent obesity and diabetes in mice that were fed a high-calorie diet and prevented from exercising, taking another step towards the target of a anti-obesity pill. The natural compound found in grapes and red wine, called resveratrol, is believed to have numerous health benefits related to longevity, heart health, and metabolism. But tests in mice suggested gallons of wine would be necessary for humans to stand a chance of getting the same benefits. The scientists turned their attention to creating a more potent drug [BBC News].
The new experimental drug, called SRT1720, was developed by the pharmaceutical company GlaxoSmithKline. Researchers explain that mice fed a high-fat diet were tricked into switching their metabolisms to a fat-burning mode that normally takes over when energy levels are low…. “We are activating the same enzymes that are activated when people go to the gym,” said Peter Elliott, a vice president at Sirtris Pharmaceuticals, the Glaxo unit that developed the drug. “That is why we believe the profile for this drug is very safe” [Reuters].
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Researchers have developed two drugs that mimic some of the effects of exercise in mice, leading to rampant speculation that people may soon be able to take a dose of “exercise in a pill.” The dramatic study showed that the drugs built fat-burning muscles in mice and increased their endurance on an exercise wheel. Four years ago researchers bred genetically engineered mice that could run much further than normal, but this is the first test to prove that drugs can have the same effect [Telegraph].
“It’s tricking the muscle into ‘believing’ it’s been exercised daily,” said the study’s lead researcher, Ronald Evans…. “It’s basically the couch potato experiment, and it proves you can have a pharmacologic equivalent to exercise” [Wired News]. One drug proved effective for mice that were already exercising regularly, increasing their running time by 68 percent and distance by 70 percent. The other drug worked on mice that hadn’t been trained to exercise; that compound increased their running time by 23 percent and distance by 44 percent.
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