Alki chi
A free Saturday morning tai chi class is once again being offered in West Seattle. Presented by Yin Yang Arts Center, the class meets from 8 to 9 a.m. until late September at Don Armeni Park (1228 Harbor Ave.), in the grassy field north of the boat-launch parking lot. No experience is needed and newcomers are encouraged. Information: 206-935-2315.

Disabled and active
The Web site for the National Center on Physical Activity and Disability (www.ncpad.org; 800-900-8086), which encourages disabled people to keep physically active to maintain good health and prevent secondary conditions, hosts interactive discussion groups on adaptive fitness and recreational equipment, programs, facilities and research. It also has a monthly newsletter, a research database and a variety of fact sheets and monographs on many conditions.

A walk for the brain
Women who walk regularly are less likely to experience memory loss and other declines in mental function that can come with aging, according to a study of nearly 6,000 women 65 and older. Subjects were tested for cognitive ability once and then again six to eight years later. The women who walked the least were most likely to develop cognitive decline: 24 percent had significant declines in their test scores, compared with 17 percent of the most active group. The least active women walked an average of about a half mile per week, while the most active group walked an average of nearly 18 miles per week. Walking included exercise and walking as part of daily activities. "We also found that for every extra mile walked per week there was a 13 percent less chance of cognitive decline," said neurologist Kristine Yaffe. "So you don't need to be running marathons."

Supplement review
Thomson Healthcare, publisher of the Physicians' Desk Reference and related series including PDRs for herbal medicines, nonprescription drugs and natural medicines, has produced a PDR for Nutritional Supplements. The 700-page book summarizes and analyzes the research data behind nutritional supplements and weighs in on the validity of health claims. Areas covered include weight loss, athletic performance, cancer fighting, disease and purported sex-enhancing supplements. It retails for $59.95 (800-678-5689).

Bicycle maneuver

Captain's chair

Crunch on a ball

Top ab exercises
Not all exercises for the abdominal muscles are created equal, according to a study sponsored by the American Council on Exercise (ACE). Researchers at San Diego State University monitored muscle activity when 30 men and women ages 20 to 45 performed 13 exercises using home, gym and no equipment, then ranked the exercises for muscle stimulation:

For strengthening the rectus abdominus (the muscle down the front of the abdomen), ranked most to least effective:

1. Bicycle maneuver
2. Captain's chair
3. Crunches on exercise ball
4. Vertical leg crunch
5. Torso Track
6. Long arm crunch
7. Reverse crunch
8. Crunch with heel push
9. Ab Roller
10. Hover
11. Traditional crunch
12. Exercise tubing pull
13. Ab Rocker

For strengthening the obliques (on the sides):

1. Captain's chair
2. Bicycle maneuver
3. Reverse crunch
4. Hover
5. Vertical leg crunch
6. Crunch on exercise ball
7. Torso Track
8. Crunch with heel push
9. Long arm crunch
10. Ab Roller
11. Traditional crunch
12. Exercise tubing pull
13. Ab Rocker

The top three, overall, were the bicycle maneuver, captain's chair and crunch on an exercise ball.

Of three pieces of infomercial equipment tested, the Torso Track was only marginally more effective than a traditional crunch and a significant number of subjects reported lower-back discomfort while using it. The Ab Roller was no more effective than a crunch and the Ab Rocker was up to 80-percent less effective.

Researcher Peter Francis recommends choosing several top-rated exercises for a daily 5-minute workout. If one exercise is uncomfortable, he says, try others until you come up with a variety that meet your needs. This will help train different areas of the muscle and prevent boredom.

Easing chemo fatigue
Daily exercise can reduce the kinds of fatigue that often accompany chemotherapy, according to last month's Medicine & Science in Sports & Exercise, the journal of the American College of Sports Medicine. Researchers at the Oregon Health Sciences University School of Nursing studied 61 women being treated for breast cancer and asked them to wear a device to measure calories expended and keep a "fatigue diary." They found that as exercise increased, fatigue level decreased, however not enough to carry over to non-exercise days. Researchers hope another study might determine realistic doses of exercise to recommend.

'I'm bored!'
If that's a familiar summertime refrain at your house, a new book by a world aerobics champion and mother of two might come in handy. "365 Activities for Fitness, Food, and Fun for the Whole Family" ($14.95, Contemporary Books) by Julia Sweet includes workouts to do with a baby or toddler, strength training and flexibility exercises using common household items, water games such as a sprinkler obstacle course, silly games like flashlight limbo, activity parties, unusual nutritious snacks that children can make themselves.

Exercise and impotence
A study of nearly 600 men over eight years found that physical activity at a level of at least 200 calories a day - the equivalent of walking briskly for 2 miles - may reduce a man's risk of developing erectile dysfunction, commonly known as impotence. Published in the August issue of Urology, the study was "the first longitudinal population-based study to show that exercise, which is beneficial for many other cardiovascular conditions, benefits sexual function as well," said author Irwin Goldstein, M.D., professor of urology at Boston University School of Medicine.

Molly Martin is assistant editor of Pacific Northwest magazine.