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December 29, 2006

Obesity is in belly

The more your belly sticks out, the greater your risk of developing heart disease, a new study shows.

"The message is really obesity in the abdomen matters even more than obesity overall," Dr Carlos Iribarren of Kaiser Permanente of Northern California in Oakland, the study's lead author, said.

Body mass index (BMI), a gauge of weight in relation to height, is a fairly crude way to judge a person's heart disease risk based on obesity, he noted. For example, muscular people may have a high BMI and be perfectly healthy

In the current study, Iribarren and his team tested whether sagittal abdominal diameter, or SAD, which is the distance from the back to the upper abdomen midway between the top of the pelvis and the bottom of the ribs, would improve the accuracy of BMI in predicting heart disease risk.

Waist circumference is widely used to measure obesity in the abdominal area, Iribarren noted. But while there are many ways to measure a person's waist, he added, SAD, which is evaluated by a doctor or nurse with a caliper, is much more standardised, and therefore probably less subject to error.

He and his colleagues looked at 101,765 men and women who underwent checkups between 1965 and 1970, which included SAD measurements, and were then followed for about 12 years.

Men with the largest SAD were 42 percent more likely to develop heart disease during follow-up compared to those with the smallest SAD, while a large SAD increased heart disease risk by 44 percent for women, Iribarren and his team found.

Within BMI categories, the researchers found, heart disease risk rose with SAD; even among men of normal weight, heart disease risk was higher for those with bigger bellies.

The relationship between SAD and heart disease risk was strongest among the youngest men and women, which is not surprising, Iribarren said, given that people who develop central obesity younger in life would likely have more serious problems.

"I think it has important implications for prevention," he said. "Don't let this happen to you when you're young, that's kind of the message."

Reuters

December 19, 2006

Two more reasons to exercise

Here are two more reasons to exercise: It may help prevent breast cancer and can be a safer way to lose weight than dieting, doctors have said.

One report from the Mayo Clinic College of Medicine in Rochester, Minnesota, said a study of women aged 55 to 69 found that those with the highest physical activity levels when the study began had a 14 percent lower risk of developing breast cancer than those who got low levels of exercise.

The multiyear study, which ended in 2003, involved more than 36,000 women.

While the mechanism involved is not clear it may be that exercise reduces body fat, the major source of estrogen in post-menopausal women, the study said. That could lead to fewer tumors of a type called estrogen receptor positive/progesterone receptor negative, which are typically more aggressive, added the report.

"Further studies are needed to confirm these novel findings, and to evaluate similar relationships among premenopausal women," concluded the report published in the Archives of Internal Medicine.

"If found to be causally related to breast cancer, physical activity would have a substantial public health effect on the prevention of this disease, along with its other positive health benefits," it added.

In another study, doctors found that people who slim down by cutting calories may also be losing bone density -- something that does not happen if weight loss comes through exercise.

Loss of bone density can lead to osteoporosis and fractures later in life.

That finding was based on a look at 48 adults involved variously in weight loss by caloric restrictions or exercise.
"A common explanation given for the bone loss induced by weight loss is reduction in mechanical stress on the weight-bearing skeleton (the hip and spine)," the report said.

But when muscles pull on bones during exercise it is thought to produce strains in the skeleton that stimulate new bone production, the researchers said.

"These findings have important implications in designing an appropriate weight-loss therapy program in middle-aged adults, particularly in the subset of patients who may already be at increased risk for bone fracture," the study concluded.

Reuters

December 12, 2006

Add Intervals to Your Workout

If you're a regular exerciser, you may have heard of "interval training." Generally speaking, it means adding short bursts of intensity - such as speed - between periods of active recovery.

The basic premise of intervals is that they allow you to get your heart rate up to a pace that you can't normally achieve during a simple moderate paced workout. But, because you can't sustain that high intensity for long periods of time, you drop down to your moderate pace for a period of "active recovery." Once you've sufficiently recovered, you do another short burst of intensity. You continue this pattern through your entire workout.

Proponents of interval training believe that it helps burn calories faster than a standard, steady-pace workout. It can also help build speed or strength in endurance athletes.

Here are some simple ways to add intervals to your workouts:

Increase speed for a set number of minutes. Pick a certain number of minutes, such as five. For the first five minutes of your workout, exercise at a moderate pace. For the next five minutes, increase your speed dramatically. When that time is over, drop your speed down to a moderate pace again for another five minutes. Repeat until you finish your workout.

Increase intensity for a set number of minutes. This tends to be easiest if you're on a piece of exercise equipment, such as an elliptical machine, treadmill or stationary bike. Again, pick a certain number of minutes, such as five. For the first five minutes of your workout, exercise at a moderate intensity (such as a 5% incline or resistance). For the next five minutes, increase the intensity (such as boosting the incline to 10%). Again, repeat this pattern until you finish your workout.

Increase speed between landmarks. Do you run or cycle outside? Pick landmarks - like telephone poles, houses or mailboxes - and increase your speed between them.

Pick a path with hills. Hills are one of the best ways to increase intensity when you're walking, running or cycling. Pick a route with lots of hills so you get varied intensity throughout your entire workout.

Increase intensity with music. Make a commitment to pick up the pace or increase the intensity of your workout whenever a fast-paced song comes on the radio. Or simply alternate: The first song is at a moderate pace, the next song is at an intense pace, the third song is at a moderate pace, and so on.

Morgan Vermeil

December 06, 2006

Chronological age be damned - it's your functional age that matters

Ask anyone who has competed in a fun run and there is every chance they remember the moment they were overtaken by a person in their 60s. As you clock up another birthday, it's not so much age that decides what you can and can't do, but how you've used your body in the preceding years.

Pitted against a seasoned 50-year-old runner, an untrained, desk-bound person in his or her 20s is likely to run out of steam first, which is why exercise physiologists no longer pigeonhole people according to age. "We think in terms of a person's functional age - meaning how active they are and what they can do physically - rather than chronological age," says exercise physiologist Chris Tzar, who is the manager of the Lifestyle Clinic at the University of NSW's faculty of medicine.

20 to 35

What to do now: These are the bulletproof years - when death or disability seemeons away and there's no urgency to fight dwindling strength or stiffening arteries. But there are advantages to exercising now. People who are active at this age have a lower mortality rate later in life than those who aren't, Tzar says. It's also smart to capitalise on the time of your life when bones are building their peak strength. The more bone you build before the mid-30s when bone density starts declining, the stronger your bones are as you age. Weight-bearing exercise such as running, speed walking, strength training and team sports all help boost bone density. Breaking a sweat now could help ward away breast cancer - there's evidence long-term exercise reduces the risk, especially in women under 45 when breast cancer is more aggressive.

Beware of: Sporting injuries that set the scene for dodgy knees and other problems in middle age. "Weekend warriors in their 20s who do nothing all week, bar a single game of soccer or netball and one training session, have a high risk of injury," says James Short, the president of the Fitness NSW Personal Trainer Council. "Adding one or two sessions of strength training through the week reduces the risk."

35 to 50

What to do now: This is when metabolism can start slowing down - a problem caused more by muscle loss than increasing age. The more muscle you have, the more energy you burn, and the easier it is to maintain a healthy weight. But unless you counter­act it, muscle loss kicks in in the 40s. By your 50s you could lose about three kilograms of muscle each decade. These are also the years when inactivity - if you let it - helps prime you for later problems such as cardiovascular disease, some cancers, diabetes, and osteoporosis.
But when every moment seems consumed by work and family, how do you stay fit?

"By spending less time working out, but working harder," Short suggests. "Instead of walking for 45 minutes or an hour, walk for 30 minutes but find a flight of steps and run - or walk briskly - up and down," he says. "Mix it up - alternate walking up one step at a time with walking up two steps at a time. Reach the top and do some push-ups. If you can only run or walk for 20 or even 10 minutes instead of 30, it's still worth it - just do it faster and harder."

As for strengthening muscles to prevent weight gain and future frailty, a gym with child care is one option for busy parents. But there are cheaper ways of getting stronger at home, Tzar says. He suggests callisthenics, such as push-ups, together with hand weights or exercise bands. "You don't have to buy hand weights - you can use two-litre milk containers filled with water or sand. As you get stronger, add more sand or water, or both, to the containers. If you're at the park with the kids, do some push-ups."

Beware of: If you're sedentary and/or a smoker, see your GP for a check-up before starting any exercise program, Tzar says. If there are any health problems, your doctor can refer you to an exercise physiologist who can prescribe a suitable exercise program. If you're diagnosed with diabetes, depression or arthritis, there's a Medicare rebate for consultations with an exercise physiologist.

50 to 65

What to do now: How you use your body now can influence how well you live later in life, but it's never too late to turn an inactive life around. German research has found that people who became physically active after 40 were 55 per cent less likely to develop heart disease than people who were inactive. The standard advice is to walk for 30 minutes on most days, preferably with two weekly strength-training sessions - but don't assume you can't do something more strenuous, providing you take it slowly.

"If you wanted to start running, you could," Tzar says. "But you'd need to get fit first by regular walking. What's important at this age is to increase the intensity of exercise gradually, in small doses - too much too soon increases the risk of injury."

Good balance is important. Strength training helps. So does increasing "core strength", meaning strengthening the muscles in your lower back, pelvis and abdomen to help keep you stable when you move around. Ways to boost core strength include Pilates, using an exercise ball or doing squats or lunges. The important thing is to activate core muscles by drawing your navel into your spine while you do these exercises, Short says. Expert advice will help you do them safely and effectively.

Beware of: "Thinking you're still in your 30s and can go back to playing soccer or touch football even though you're overweight and haven't trained for 20 years," Short warns. "With contact sports, there's a higher risk of injuries. At this age muscles are less elastic - any injuries take longer to heal."

65-plus

What to do now: All aspects of fitness are important, but strength training is of the greatest benefit to people of this age, Short says. "People often lose confidence, but I find that when they feel stronger they're more confident - they're not scared about living alone, and because physical tasks are easier to do, they get less tired and have more energy."

Beware of: Believing you're too old to embrace physical activity. "You can continue to adapt and improve at any age," Tzar says.

Fitness at any age

Ideally we should nurture all four aspects of fitness at all ages ¿ it makes everything you do easier and safer.

* Aerobic fitness increases your body's ability to use oxygen and conditions the heart and lungs. Maintain them with regular walking, swimming, cycling, running or dancing.

* Build muscle strength using dumbbells, barbells, resistance bands, weight machines or your own body weight (for example, in a push-up).

* Flexibility allows you to move your joints through their full range of motion. Stay flexible with stretching exercises, yoga, and tai chi.

* Strong "core" muscles in your lower back, pelvis, hips and abdomen help maintain your balance. Stay on your feet with regular exercise and strength training.

Paula Goodyer
December 1, 2006
www.smh.com.au

December 04, 2006

Eating slowly really does make people eat less

A new study provides the first ever scientific proof that if you eat slowly, you will eat less and enjoy the meal more.

Women consumed about 70 fewer calories when they were told to take their time eating a meal of pasta and sauce, compared to when they were instructed to eat it as quickly as possible.

They also rated the meal as more pleasant when they ate slowly.

"They got more pleasure for (fewer) calories, and more satiety," Dr Kathleen Melanson of the University of Rhode Island in Kingston said.

Melanson decided to conduct the study when she learned there was no research to support the familiar claim that eating slowly reduces appetite.

She and her colleagues had 30 young women eat a meal of ditalini with tomato and vegetable sauce, topped with Parmesan cheese, under two different conditions.

Before each meal, the women had eaten a standard 400-calorie breakfast, and then fasted for four hours.

At one visit to the lab, study participants were given a large spoon and told not to pause between bites and to eat as quickly as possible. At the other, participants ate with a small spoon, which they put down after each bite, and were told to take small bites and chew each bite 15 to 20 times.

When eating quickly, the women took in an average of 646 calories in nine minutes.

But when they slowed down, they consumed 579 calories in 29 minutes, according to their report, presented at the annual meeting of the North American Association for the Study of Obesity.

The women felt fuller and more satisfied immediately after they ate the meal and an hour later when they had consumed it slowly, Melanson and her colleagues found.

Eating slowly may indeed promote weight loss, or help people maintain a healthy weight, Melanson noted, given that someone who ate three leisurely meals might consume 210 fewer calories a day than someone who wolfed those meals down.

Reuters