Health News

REPORTING POINT 05/12

HEALTH NEWS

“Live healthy...Live well”

Dedicated to providing pertinent information on health, fitness, and nutrition to foster a culture of wellness among Southwest Airlines flight crews and their families.

by Larry Kline

email: livehealthy-livewell@cox.net

INTERVAL TRAINING – there is more than one way to get more out of your cardiovascular workout – interval training.  Coaches and trainers have used it for many years and recent research has confirmed its benefits and brought it new attention.

            Interval training involves alternating short bursts of intense and moderate exertion.  It can be done with any kind of cardiovascular exercise, such as running, cycling, swimming, or stair climbing.  An example of interval training would be cycling very hard for two minutes, then pedaling for two minutes at a more relaxed pace, then speed up again and so on.

            Studies have found that interval training can improve endurance and fitness better than moderate-intensity workouts at a steady pace and in less time.  It can also improve blood sugar control, lower blood pressure, and raise HDL cholesterol.   Interval training helps improve the efficiency and endurance of muscles by making them alternate between aerobic exertion (in which oxygen is used to burn carbohydrates and fat for energy) and anaerobic exertion (without oxygen).  It may allow exercisers to maintain a higher overall intensity because they know that recovery periods are coming up.  The recovery periods also allow for the removal of some lactic acid that accumulates in the muscles and makes them tire.

            Norwegian studies have shown that supervised interval training can improve cardiovascular health, the ability to exercise and quality of life in people with heart failure more than low- to moderate-intensity exercise.  Another study compared interval and regular training in people who had coronary artery bypass surgery. This study found that interval training provided greater benefits in endurance and in the ability to tolerate spurts of exertion.

            If you want to try interval training, start with two or three sessions a week.  If you run, just speed up for one to four minutes, then slow down for a similar period. then keep alternating.  If you are comfortable with this, try increasing the length or intensity of the strenuous bouts.  You can also vary the length of the slower bouts (which can be shorter or longer than the intense spurts), as well as the length or intensity of the workout.

            The intense bouts should get your heart rate up to 85 to 90 percent of its maximum (you can compute your maximum heart rate by subtracting your age from 220 beats per minute). 

            Keep in mind, if weight loss is one of your exercise goals, there is no shortcut.  Though interval training burns lots of calories in a short period, it takes longer, moderate-intensity workouts to produce and maintain weight loss.  University of California Berkeley Wellness Letter 6/10.

Strong Arm Diabetes - Building muscle can lower your insulin resistance risk, thus lowering your chance of developing Type-2 Diabetes. Scientists have known for a while that low muscle mass raises the risk of insulin resistance; however, no study had attempted to figure out whether increased muscle, regardless of obesity levels, might improve blood glucose control. Journal of Clinical Endocrinology & Metabolism, 07/11.

TEA FACTS – black, green, white, or oolong teas are all made from the leaves of the Camellia sinensis  plant. Herbal teas like chamomile and peppermint are not technically considered tea as they have different nutritional characteristics.

            What makes the four tea types different from each other is the way the leaves are prepared and how mature the leaves are, which affects both flavor and nutritional content.

            Black tea is made from leaves that have been wilted (dried out) and then fully oxidized (meaning that chemicals in the leaves are modified through exposure to air).  Green tea’s leaves are wilted but not oxidized.  Oolong tea is wilted and then only partially oxidized, and white tea is not wilted or oxidized at all.

            All four types are high in polyphenols, a type of antioxidant that seems to protect cells from the DNA damage that can cause cancer and other diseases.  Most research into the benefits of tea has focused on black tea, which is what 75 percent of the world drinks, and green tea, the most commonly consumed variety in China and Japan.  Green tea contains an especially high amount of antioxidants – in particular a type of polyphenol called catechin, the most active and abundant of which is epigallocathechin-3-gallate (EGCG).  Drinking tea may have the following health benefits:

            -Cancer prevention.  A 2009 review of 51 green tea studies found that consuming three to five cups a day may lower the risks of ovarian, colorectal, lung, and prostate cancers, but not breast or other cancers.  Black tea has been deemed possibly effective for reducing the risk of ovarian cancer, and possibly ineffective for lowering the risk of stomach and colorectal cancers by the National Institutes of Health.

            -Brain benefits. Drinking one to four cups of black or green tea a day has been linked with a lower risk of Parkinson’s disease, according to the NIH.

            -Heart benefits. Drinking tea may be helpful in preventing or delaying certain risk factors of cardiovascular disease, and lowering LDL (bad) cholesterol and triglycerides.  One Japanese study found that adults who drank five or more cups of green tea per day had a 26 percent reduction in death from heart attack or stroke compared with those who had one cup or less; the effect was greater in women than in men.  Research shows that that green tea lowers blood cholesterol by reducing its absorption in the digestive tract, while increasing its rate of excretion. More important than taking away excess cholesterol is green tea’s ability to fight the conversion of LDL to its more dangerous, oxidized form. When LDL is oxidized, it gets sticky and tends to cling to the walls of your arteries. Oxidized LDL is a major factor in the development of atherosclerosis (the buildup of plaque in the arteries), and greatly increases your risk of a heart attack or stroke. Green tea, through its antioxidant action, does much to protect LDL from oxidation, thus helping to keep your arteries “clean.”

            -Weight loss. Some studies suggest that the catechins and caffeine in green tea may give dieters a small metabolic boost that could amount to burning a few dozen extra calories per day.

            -Immune response. EGCG, the green-tea antioxidant, has been found to increase the number of important immune-boosting cells (regulatory T-cells).

HERBAL TEAS

            There are as many varieties of herbal teas as there are plants and flowers, some of which have healing potential.  As with “regular” tea, there has not been definitive research on humans when it comes to these drinks, but preliminary studies suggest benefits.  Chamomile and peppermint, for instance, contain moderate levels of antioxidants and have antimicrobial qualities (meaning they could improve oral-health).  Chamomile has been shown to have anti-inflammatory and cholesterol-lowering effects in animal studies. Peppermint tea eases gastrointestinal upset, according to a 2006 review of research.  Three cups a day for six weeks of hibiscus tea lowered blood pressure significantly in people with mildly elevated levels.  Health 11/2011,Journal of American Dietetic Association 11/11.

Where to Eat?  - As childhood obesity rises and the American diet shifts towards increasing consumption of foods eaten or prepared outside of the home, concerns about the nutritional quality and the total consumption of such foods are also increasing. Comparing measurements from 2006 to 1977, children now eat more calories every day (+179 kcal/day). This is associated with a major increase in calories eaten away from home (+255 kcal/day). The percentage of calories eaten away from home is now 33.9 percent. Journal of the American Dietetic Association, 08/11.

CALCIUM FOR YOUR DIET – according to University of Tennessee researchers, dieters who got 1,200 to 1,300 milligrams of daily calcium saw three times the weight loss as those consuming the same calories but less calcium. 

Research published in the International Journal of Obesity indicated that the calcium from yogurt, rather than other dairy sources or supplements, was more beneficial in aiding weight loss. Health 10/08.