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Strength-training will make women too muscular.
“Many women are afraid that strength-training will make them bulky,” says Miriam Nelson of the Jean Mayer U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University in Boston. “They think strength-training is only for men.”
In fact, strength-training has enormous benefits for women. In one of Nelson’s studies, postmenopausal women who were sedentary were randomly assigned to do strength-training exercises twice a week or to do no additional exercise. After a year, the strength-trainers had greater bone density, muscle mass, muscle strength, and balance than the sedentary women.1
“Women naturally have less bone and muscle than men, so they need to take care of what they've got,” says Nelson. That's why women are at greater risk of osteoporosis than men. And lost muscle puts women at greater risk of disability as they age.
“Thirty percent of middle-aged women have trouble doing physical tasks like walking a mile or carrying a few grocery bags or climbing a few flights of stairs,” says Nelson. “Its pretty staggering. They're really out of shape.”
And don’t worry about looking like a bodybuilder. “Women don't have enough testosterone to create big, bulky muscles,” says Nelson. “To become a bodybuilder, women have to do a lot of weird things that most strength-training programs don't do.”
1J. Amer. Med Assoc. 272: 1909, 1994
Illustrations: Loel Barr
Weight gain is inevitable as you age.
Most Americans get fatter as they get older... but they don’t have to. “It’s a matter of reduced physical activity levels and lower metabolic rate caused by a loss of lean body mass [muscle],” says JoAnn Manson of Harvard Medical School.
“The lifelong loss of lean body mass reduces our basal metabolic rate as we age,” says Arkansas’s William Evans. “It’s a very subtle change that begins between ages 20 and 30. The percentage of body fat gradually increases, and it produces an ever-decreasing calorie requirement.”
That’s because fat cells burn fewer calories than muscle cells. And a lower metabolic rate means that unless you eat less, you’ll gain weight over the decades.
But exercise can mount a two-pronged attack on middle-age spread and muscle loss. Any activity makes you burn more calories (so you’re less likely to wind up with an excess). And strength-training can offset the loss of muscle mass.
“Starting at age 40 in women and at 60 in men, we lose six to eight percent of our muscle per decade,” says Maryland's Hurley. “However, after only two months of strength-training, women recover a decade of loss and men recover two decades.”
That’s with three weekly sessions that take 40 minutes each, including warm-up, rest periods, and stretching.1 “The time spent doing the exercises that increase muscle mass is only about five minutes a session,” says Hurley. Not a bad return on your time.
1 J. Appl. Physiol. 86: 195, 1999.
Illustrations: Loel Barr
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12 Good reasons to workout
Sleep
A 16-week exercise program (30 to 40 minutes of brisk walking or low-impact aerobics four times a week) improved the quality, duration, and ease of falling asleep in healthy older adults.1 Exercise may improve sleep by relaxing muscles, reducing stress, or warming the body.
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Gallstones
Active women are 30 percent less likely to have gallstone surgery than sedentary women. In one study, women who spent more than 60 hours a week sitting at work or driving were twice as likely to have gallstone surgery as women who sat for less than 40 hours a week.2
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Colon Cancer
The most active people have a lower risk of colon cancer — in two studies half the risk — compared to the least active people.3,4 Exercise may lower levels of prostaglandins that accelerate colon cell proliferation and raise levels of prostaglandins that increase intestinal motility. Increased motility may speed the movement of carcinogens through the colon.
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Diverticular Disease
In one of the few studies that have been done, the most active men had a 37 percent lower risk of symptomatic diverticular disease than the least active men.5 Most of the protection against diverticular disease--pockets in the wall of the colon that can become inflamed--was due to vigorous activities like jogging and running, rather than moderate activities like walking.
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Arthritis
Regular moderate exercise, whether aerobic or strength-training, can reduce joint swelling and pain in people with arthritis.6
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Anxiety & Depression
Getting people with anxiety or depression to do aerobic exercises like brisk walking or running curbs their symptoms, possibly by releasing natural opiates.7,8
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Heart Disease
In one study, men with low fitness who became fit had a lower risk of heart disease than men who stayed unfit.9 In another, women who walked the equivalent of three or more hours per week at a brisk pace had a 35 percent lower risk of heart disease than women who walked infrequently.10 Exercise boosts the supply of oxygen to the heart muscle by expanding existing arteries and creating tiny new blood vessels. It may also prevent blood clots or promote their breakdown.
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Blood Pressure
If your blood pressure is already high or high-normal, low- or moderate-intensity aerobic exercise — three times a week — can lower it.11 If your blood pressure isn't high, regular exercise helps keep it that way.
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Diabetes
The more you move, the lower your risk of diabetes, especially if you're already at risk because of excess weight, high blood pressure, or parents with diabetes. In one study, women who walked at least three hours a week had about a 40 percent lower risk of diabetes than sedentary women.12
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Falls & Fractures
Older women assigned to a home-based (strength- and balance-training) exercise program had fewer falls than women who didn't exercise. 13 Exercise may prevent falls and broken bones by improving muscle strength, gait, balance, and reaction time.
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Enlarged Prostate (men only)
In one study, men who walked two to three hours a week had a 25 percent lower risk of benign prostatic hyperplasia (enlarged prostate) than men who seldom walked.14
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Osteoporosis
Exercise, especially strength-training, can increase bone density in middle-aged and older people.15 Bonus: postmenopausal women who take estrogen gain more bone density if they exercise.
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1 J. Amer. Med. Assoc. 277: 32, 1997.
2 N. Eng. J. Med. 341: 777, 1999.
3 J. Nat. Cancer Inst. 89: 948, 1997.
4 Ann. Intern. Med. 122: 327, 1995.
5 Gut 36: 276, 1995.
6 J. Amer. Med. Assoc. 277: 25, 1997
7 J. Psychosom. Res. 33: 537, 1989.
8 Arch. Intern. Med. 159: 2349, 1999.
9 J. Amer. Med. Assoc. 273: 1093, 1995.
10 N. Eng. J. Med. 341: 650, 1999.
11 J. Clin. Epidem. 45: 439, 1992
12 J. Am. Med. Assoc 282: 1433, 1999.
13 Brit. Med. J. 315: 1065, 1997.
14 Arch. Intern. Med. 158: 2349, 1998.
15 J. Bone Min. Res. 11: 218, 1996.
If you can’t exercise regularly, why bother?
It takes ten to 12 weeks of regular exercise to become “fit” — that is, to improve your performance on a treadmill (a measure of your oxygen capacity). But your health can improve after that first brisk walk or run.
“Take a 50-year-old man who is somewhat overweight and typically has moderately elevated blood sugar, triglycerides, or blood pressure,” says Stanford’s William Haskell. “A single bout of exercise of moderate intensity — like 30 to 40 minutes of brisk walking — will lower those numbers.”
And not just while you’re moving. “If you exercise at, say, five o’clock in the afternoon, the improvement will be there the next morning,” he adds.
That may be why postal carriers (or others who are active at work) have a lower risk of heart disease than postal clerks (or others who are sedentary at work). “There’s not much difference in their fitness levels, but the carriers have lower blood sugar, triglycerides, and blood pressure,” says Haskell.
People should still try to at least follow the Center for Disease Control’s modest advice to get at least 30 minutes of moderate activity on most — or preferably all — days of the week, he adds. But if you can’t, don’t let that stop you from taking even a single walk.
“Every bout has benefits,” says Haskell.
If you don't lose weight, there's no point in exercising.
What gets most people off the couch and into their walking shoes? It’s that unwanted flab that motivates most of us. It shouldn’t.
“Many people don’t see immediate weight loss and say it’s all for naught and stop,” says exercise expert William Haskell of Stanford University Medical School.
In fact, exercise has a laundry list of benefits beyond any impact on your next shopping trip (see “A Dozen Other Reasons to Exercise”). Among them:
“It improves the ability of insulin to enter cells, so it lowers the risk of diabetes,” says Haskell. “It also lowers the risk of heart disease by improving blood clotting mechanisms, lowering triglycerides, and raising HDL [‘good’] cholesterol.”
Exercise alters not only your risk of disease, but your quality of life, he adds. “In our studies, exercise improved sleep in people with modest sleep dysfunction,” that is, people who take a long time to fall sleep or who wake up frequently at night.
“The psychological benefits of exercise are frequently overlooked,” says Haskell. “Exercise isn’t a panacea, but it has consistently been shown to relieve both depression and anxiety.”
Food Additives to Avoid
(Listed alphabetically)
Acesulfame K
Known commercially as Sunette or Sweet One, acesulfame is a sugar substitute sold in packet or tablet form, in chewing gum, dry mixes for beverages, instant coffee and tea, gelatin desserts, puddings and non-dairy creamers. Tests show that the additive causes cancer in animals, which means it may increase cancer in humans. Avoid acesulfame K and products containing it. Your sweet tooth isn't worth it.
Artificial colorings
The great bulk of artificial colorings used in food are synthetic dyes. For decades synthetic food dyes have been suspected of being toxic or carcinogenic and many have been banned. Whenever possible, choose foods without dyes. They're mostly used in foods of questionable nutritional worth anyway. Natural ingredients should provide all the color your food needs.
Aspartame
This sugar substitute, sold commercially as Equal and NutraSweet, was hailed as the savior for dieters who for decades had put up with saccharine's unpleasant after taste. There are quite a few problems with aspartame. The first is phenylketonuria (PKU). One out of 20,000 babies is born without the ability to metabolize phenylalanine, one of the two amino acids in aspartame. Toxic levels of this substance in the blood can result in mental retardation. Beyond PKU several scientists believe that aspartame might cause altered brain function an behavior changes in consumers. And many people (though a minuscule fraction) have reported dizziness, headaches, epileptic-like seizures, and menstrual problems after ingesting aspartame.
Avoid aspartame if you are pregnant, suffer from PKU, or think that you experience side affects from using it. If you consume more than a couple of servings a day consider cutting back. And, to be on the safe side, don't give aspartame to infants.
BHA & BHT
These two closely related chemicals are added to oil-containing foods to prevent oxidation and retard rancidity. The International Agency for Research on Cancer, part of the World Health Organization, consider BHA to be possibly carcinogenic to humans, and the State of California has listed it as a carcinogen. Some studies show the same cancer causing possibilities for BHT.
BHT and BHA are totally unnecessary. To avoid them read the label. Because of the possibility that BHT and BHA might cause cancer, both should be phased out of our food supply. To play it safe, phase them out of your diet.
Caffeine
Caffeine is found naturally in tea, coffee, and cocoa. It is also added to many soft drinks. It is one of the few drugs -- a stimulant -- added to foods. Caffeine promotes stomach-acid secretion (possibly increasing the symptoms of peptic ulcers), temporarily raises blood pressure, and dialates some blood vessels while constricting others. Excessive caffeine intake results in "caffeinism," with symptoms ranging from nervousness to insomnia. These problems also affect children who drink between 2 to 7 cans of soda a day. Caffeine may also interfere with reproduction and affect developing fetuses. Experiments on lab animals link caffeine to birth defects such as cleft palates, missing fingers and toes, and skull malformations.
Caffeine is mildly addictive, which is why some people experience headaches when they stop drinking it. While small amounts of caffeine don't pose a problem for everyone, avoid it if you are trying to become or are pregnant. And try to keep caffeine out of you child's diet.
Monosodium Glutamate (MSG)
Early in this century a Japanese chemist identified MSG as the substance in certain seasonings that added to the flavor of protein-containing foods. Unfortunately, too much MSG can lead to headaches, tightness in the chest, and a burning sensation in the forearms an the back of the neck. If you think you are sensitive to MSG, look at ingredient listings. Also, avoid hydrolyzed vegetable protein, or HVP, which may contain MSG.
Nitrite and Nitrate
Sodium nitrite and sodium nitrate are two closely related chemicals used for centuries to preserve meat. While nitrate itself is harmless, it is readily converted to nitrite. When nitrite combines with compounds called secondary amines, it forms nitrosamines, extremely powerful cancer-causing chemicals. The chemical reaction occurs most readily at the high temperatures of frying. Nitrite has long been suspected as being a cause of stomach cancer. Look for nitrite-free processed meats -- some of which are frozen, refrigeration reduces the need for nitrites -- at some health food and grocery stores. But regardless of the presence of nitrite or nitrosamines, the high-fat, high-sodium content of most processed meats should be enough to discourage you from choosing them. And don't cook with bacon drippings.
Olestra
Olestra, the fake fat made by Procter and Gamble, is both unsafe and unnecessary. Olestra was approved over the objection of dozens of leading scientists.
The additive may be fat-free but it has a fatal side-effect: it attaches to valuable nutrients and flushes them out of the body. Some of these nutrients -- called carotenoids -- appear to protect us from such diseases as lung cancer, prostate cancer, heart disease, and macular degeneration. The Harvard School of Public Health states that "the long-term consumption of olestra snack foods might therefore result in several thousand unnecessary deaths each year from lung and prostate cancers and heart disease, and hundreds of additional cases of blindness in the elderly due to macular degeneration. Besides contributing to disease, olestra causes diarrhea and other serious gastrointestinal problems, even at low doses."
FDA certified olestra despite the fact that there are safe low-fat snacks already on the market. There is no evidence to show that olestra will have any significant effect on reducing obesity in America.
Despite being approved as safe by the FDA, all snacks containing olestra must carry a warning label (similar to one found on cigarettes) that states:
This Product Contains Olestra. Olestra may cause abdominal cramping and loose stools. Olestra inhibits the absorption of some vitamins and other nutrients. Vitamins A, D, E, and K have been added.
As of May 2000, more than 18,000 consumers have submitted to the FDA reports of adverse reactions that they attributed to olestra. That’s more reports than the FDA has received for all other additives in history -- combined.
Potassium Bromate
This additive has long been used to increase the volume of bread and to produce bread with a fine crumb (the non-crust part of bread) structure. Most bromate rapidly breaks down to form innocuous bromide. However, bromate itself causes cancer in animals. The tiny amounts of bromate that may remain in bread pose a small risk to consumers. Bromate has been banned virtually worldwide except in Japan and the United States. It is rarely used in California because a cancer warning might be required on the label.
Saccharin
Several studies in the 1970s linked saccharin with cancer in laboratory animals. Avoid it. Sweetener packets and cans of saccharin-containing diet drinks bear warning labels: "Use of this product may be hazardous to your health. This product contains saccharin, which has been determined to cause cancer in laboratory animals."
In May 2000, the government revised its position on saccharin and said that while saccharin causes bladder cancer in animals it does not cause cancer in humans. CSPI disagrees with those decisions. Later that year, Congress passed a law removing the warning label from products.
Sulfites
Sulfites are a class of chemicals that can keep cut fruits and vegetables looking fresh. They also prevent discoloration in apricots, raisins, and other dried fruits; control "black spot" in freshly caught shrimp; and prevent discoloration, bacterial growth, and fermentation in wine. Until the early 80's they were considered safe, but CSPI found six scientific studies proving that sulfites could provoke sometimes sever allergic reactions. CSPI and the Food and Drug Administration (FDA) identified at least a dozen fatalities linked to sulfites. All of the deaths occurred among asthmatics. In 1985 Congress finally forced FDA to ban sulfites from most fruits and vegetables. Especially if you have asthma, be sure to consider whether your attacks might be related to sulfites. The ban does not cover fresh-cut potatoes, dried fruits, and wine.
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