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In a head-to-head comparison, two popular weight loss methods proved equally effective at helping participants lose significant amounts of weight. But, in a surprising twist, a low-carbohydrate diet proved better at lowering blood pressure than the weight-loss drug orlistat, according to researchers at Veterans Affairs Medical Center and Duke University Medical Center.

 

The findings send an important message to hypertensive people trying to lose weight, says William S. Yancy, Jr., MD, lead author of the study in the Jan. 25 Archives of Internal Medicine, and an associate professor of medicine at Duke. "If people have high blood pressure and a weight problem, a low-carbohydrate diet might be a better option than a weight loss medication."

Yancy added, "It's important to know you can try a diet instead of medication and get the same weight loss results with fewer costs and potentially fewer side effects."

Studies had already indicated that a low-carbohydrate diet and prescription-strength orlistat combined with a low-fat diet are effective weight loss therapies. But the two common strategies had not been compared to each other, an important omission now that orlistat is available over-the-counter. In addition, few studies provide data on these treatments for overweight patients with chronic health issues.

That's what made these findings particularly interesting, says Yancy, a staff physician at the Durham VA where the research was conducted. The 146 overweight participants in the year-long study had a range of health problems typically associated with obesity -- diabetes, high blood pressure, high cholesterol and arthritis.

 

"Most participants in weight loss studies are healthy and don't have these problems," he said. "In fact they are often excluded if they do."

The average weight loss for both groups was nearly 10 percent of their body weight. "Not many studies are able to achieve that," says Yancy, who attributes the significant weight loss to the group counseling that was offered for 48 weeks. In fact, he says "people tolerated orlistat better than I expected. Orlistat use is often limited by gastro-intestinal side effects, but these can be avoided, or at least lessened, by following a low-fat diet closely. We counseled people on orlistat in our study fairly extensively about the low-fat diet."

In addition to achieving equal success at weight loss, the methods proved equally effective at improving cholesterol and glucose levels.

But Yancy said it was the difference in blood pressure results that was most surprising.

 

Nearly half (47%) of patients in the low-carbohydrate group had their blood pressure medication decreased or discontinued while only 21 percent of the orlistat plus low-fat diet group experienced a reduction in medication use. Systolic blood pressure dropped considerably in the low-carbohydrate group when compared to the orlistat plus low-fat diet group.

"I expected the weight loss to be considerable with both therapies but we were surprised to see blood pressure improve so much more with the low-carbohydrate diet than with orlistat," says Yancy, who says the mechanism is unclear. "While weight loss typically induces improvements in blood pressure, it may be that the low-carbohydrate diet has an additional effect." That physiologic effect may be the subject of future studies.

T

he bottom line, says Yancy, is that many diet options are proving effective at weight loss. But it's counseling patients on how to best follow the options that appears to be making the biggest impact. "It is clear now that several diet options can work, so people can be given a choice of different ways to lose weight. But more importantly, we need to find new ways to help people maintain their new lifestyle."

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Listening to an iPod, Pandora radio, or any in ear music, while working out feels like second nature to many people, but University of Alberta researcher Bill Hodgetts says we need to consider the volume levels in our earphones while working up a sweat.

 

Hodgetts, assistant professor in the Department of Speech Pathology and Audiology at the Faculty of Rehabilitation Medicine, says his research has found that exercising in a gym often prompts people to turn up the volume to potentially unsafe levels for the ear.

 

The researcher found that the study participants, who were in a gym-like setting, listened at potentially dangerous levels while working out, likely due to the presence of background noise. But he says it isn't the listening level alone that's risky, it's how long a person listens at that level. What Hodgetts found is that almost half of his study participants listened for a length of time during exercise that put them at risk for hearing loss.

 

The good news? The solution is simple, he says: get better earphones, those that "seal" the ear canal, acting as an earplug and thus reducing background noise.

Hodgetts' mission is to get the message out that proper earphones will make a huge difference in auditory health while allowing people to enjoy music at a lower, and safer volume

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Knee osteoarthritis (OA) accounts for more disability in the elderly than any other disease. Running, although it has proven cardiovascular and other health benefits, can increase stresses on the joints of the leg. In a study published in the December 2009 issue of PM&R: The journal of injury, function and rehabilitation

, researchers compared the effects on knee, hip and ankle joint motions of running barefoot versus running in modern running shoes. They concluded that running shoes exerted more stress on these joints compared to running barefoot or walking in high-heeled shoes.

 

Sixty-eight healthy young adult runners (37 women), who run in typical, currently available running shoes, were selected from the general population. None had any history of musculoskeletal injury and each ran at least 15 miles per week. A running shoe, selected for its neutral classification and design characteristics typical of most running footwear, was provided to all runners. Using a treadmill and a motion analysis system, each subject was observed running barefoot and with shoes. Data were collected at each runner's comfortable running pace after a warm-up period.

The researchers observed increased joint torques at the hip, knee and ankle with running shoes compared with running barefoot. Disproportionately large increases were observed in the hip internal rotation torque and in the knee flexion and knee varus torques. An average 54% increase in the hip internal rotation torque, a 36% increase in knee flexion torque, and a 38% increase in knee varus torque were measured when running in running shoes compared with barefoot.

 

These findings confirm that while the typical construction of modern-day running shoes provides good support and protection of the foot itself, one negative effect is the increased stress on each of the 3 lower extremity joints. These increases are likely caused in large part by an elevated heel and increased material under the medial arch, both characteristic of today's running shoes.

Writing in the article, lead author D. Casey Kerrigan, MD, JKM Technologies LLC, Charlottesville, VA, and co-investigators state, "Remarkably, the effect of running shoes on knee joint torques during running (36%-38% increase) that the authors observed here is even greater than the effect that was reported earlier of high-heeled shoes during walking (20%-26% increase). Considering that lower extremity joint loading is of a significantly greater magnitude during running than is experienced during walking, the current findings indeed represent substantial biomechanical changes." Dr. Kerrigan concludes, "Reducing joint torques with footwear completely to that of barefoot running, while providing meaningful footwear functions, especially compliance, should be the goal of new footwear designs."

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