Fat or fiction?
LONDON: Working out can be not only tough and time-consuming, it is often downright bamboozling because there is so much information to comprehend. We looked at how the five biggest fitness myths stack up against scientific fact.
You can spot-reduce fat
A new study reveals that running is not as damaging to the knees as previously believed. AFP |
The diet and fitness industries have traded for so long on the concept of targeting specific body parts for fat removal - hip-and-thigh eating plans, bums, stomachs and thigh workouts etc - that quite a few people have actually come to believe that spot-reduction is possible. But scientific studies cast doubt on the possibility of selectively taking inches off the waist, thighs or buttocks.
Dr Cedric Bryant, chief science officer for the American Council on Exercise, a consumer watchdog for the fitness industry, says there is little evidence to support such claims.
The spot-reduction theory was tested at the University of Massachusetts where 13 male subjects did a vigorous abdominal exercise program for one month. Each subject performed 5,000 sit-ups over 27 days. But when fat biopsies from their stomachs, buttocks and upper backs obtained at the beginning and end of the trial were analyzed, fat loss proved similar at all three sites, not just the abdomen.
"If caloric expenditure is enough, it will cause fat from the entire body, including that from a target area, to be reduced," Bryant says. "However, although fat is lost from the entire body through exercise and calorie reduction, it appears that the last areas to become lean tend to be those areas where an individual tends to gain fat first.
"For most men, that is the abdominal region and for women it is hips, buttocks and thighs."
Running is bad for your knees
A recent study showed running actually protects knee joints from damage and pain.
Reporting in the journal Arthritis Research and Therapy, a team from the department of immunology and rheumatology at Stanford University in southern California found adults who run consistently can expect to have 25 percent less musculoskeletal pain and less arthritis than non-runners when they get older.
Dr Bonnie Bruce, the study author, followed more than 500 runners from a local club (called "ever runners" in the study) and 300 inactive people ("never runners", but not necessarily sedentary) in their 50s and 60s for 14 years.
Bruce and her colleagues found that the "ever runners", who ran at least six hours per week on average, experienced less joint pain by their 60s and 70s and only 35 percent of the joggers got arthritis (compared to 43 percent of non-runners).
Sammy Margo, a sports physiotherapist for the Chartered Society of Physiotherapy, says running doesn't deserve its bad press.
"The key is consistency," Margo says. "If you run consistently, your joints, tendons, ligaments, disks and muscles get used to the habitual pounding of the activity. The body accommodates and copes with the demands."
Yoga is good for back pain
Contorting yourself like a pretzel on a yoga mat may be good for many things but not, apparently, for your back. In a study published in the Annals of Internal Medicine, researchers found that a gentle yoga class seemed a better alternative to "either general exercise or a self-help book" for back pain.
However, Dr Karen Sherman who conducted the study conceded that more vigorous types of yoga, such as ashtanga, and classes led by poorly qualified instructors, can potentially make problems worse.
Staying active, though, is important, although back-pain sufferers should do so only on the advice of their physiotherapist.
Jeremy Fairbank, consultant orthopaedic surgeon at the Nuffield Hospital, Oxford, found that patients obtain as much benefit from an intense program of exercise therapy as from spinal surgery.
Fairbank's trial, funded by the Medical Research Council and involving almost 350 patients, revealed that those who followed a tailored daily exercise program involving activities such as step-ups, walking on a treadmill, cycling and core stability work for five days over three weeks made huge progress.
Pilates gives you a star body
Fans are reported to include Madonna, Jodie Foster and Liz Hurley, but while the cult gym practice might leave you with a super-strong core or middle-section, it will do little to improve your cardiovascular fitness and lower body fat, at least according to the results of a study by the American Council on Exercise (ACE).
A University of Wisconsin study analyzed the demands of 50-minute beginner and advanced level Pilates classes and found the intensity of each to be lower than the recommended level for improving cardiovascular fitness.
In the beginners' classes, the maximum heart rate of the healthy and moderately fit female subjects was only 54 percent when the accepted range for boosting fitness is 64-94 percent. They burned 175 calories. Even the advanced class failed to raise heart rates above an average 62 percent and burned only 254 calories, equivalent to the benefits gained from walking at a slow pace.
In order to get fitter and slimmer, the experts suggest Pilates be done in conjunction with aerobic activities such as running or cycling.
You don't need to 'feel the burn'
Current recommendations suggest that totting up half an hour of activity by performing tasks such as housework, gardening or collecting the newspaper is enough to keep us healthy. But these are minimum requirements (even though many barely manage to meet them) and if you really want to shape up, it requires a lot more sweat and toil.
Research by the American College of Sports Medicine (ACSM) sets what are widely regarded as the core targets of exercising three to five times a week for 20 to 60 minutes at 55-90 percent of your body's maximum capacity, calculated according to your heart rate, if you want to improve fitness.
"That constitutes a fairly vigorous workout that would leave you breathless and puffing," says Dr Greg Whyte, sports science coordinator for the English Institute of Sport. "And it is the level you need to be doing if you want to get fitter."
That doesn't mean we can rest on our laurels for the rest of the time. Whyte believes too many people have "reached a point where they think going to the gym three times a week is enough".
But, he says, while working out will contribute considerably towards overall fitness, "there are 23 and a bit hours remaining in the day and we should try to be active at least during some of them."
It doesn't end there. Louise Sutton, senior lecturer in health and exercise science at Leeds Metropolitan University, says that there has to be an element of progression in a workout regimen.
"The body and its muscles respond to the overload principle," she says. "And there comes a time when you will need to extend the duration or intensity of your exercise to get fitter still."
The Guardian
(China Daily 06/13/2007 page19)
