Jupiterimages/Goodshot/Thinkstock(NEW YORK) -- For years infomercials have played off the elusive dream of one-stop fitness -- a contraption or exercise routine that provides a total body workout to those big and small, young and old.
This one-size-fits-all approach is misguided, according to exercise experts. We should be exercising according to the kind of life we lead -- each person is going to bring different exercise needs to the table according to their personal preference and physical capabilities.
ABC News asked leading fitness experts and kinethseiologists to weigh in on which exercises are a best fit for people of various ages, stages of life and level of fitness. As always, experts recommend consulting with a physician before starting any exercise program.
The Couch Potato, aka the Exercise Newbie
-- Expert Favorite: Walking plus weight lifting
Former couch potatoes should resist the temptation to jump on the treadmill, fitness experts warn. Exercise tolerance -- the amount of exertion one's body can handle -- "is not something to be messed with," says Jason West, clinical assistant professor in the exercise and sports medicine department at the University of Tulsa.
For people who haven't been active in a long time, "they're almost like a kid in their training age. Their room for gain is huge, but they're going to have muscle soreness or injuries if they don't start slow," he says.
West recommends starting with a walking program, supplemented with some weight training on machines. Because lifting free weights requires balancing the body while lifting, weight lifting machines are a good place to start because people can "just sit in a comfortable position and focus on one muscle group," he says.
The Single Parent on a Tight Schedule
-- Expert Favorite: Housework Training
For parents who don't feel that they can dedicate a chunk of time to a workout, Billy Davis, director of personal training at Complete Body and Spa in New York City, suggests embracing household chores and playtime with kids as a way to amp up activity levels.
For parents who feel they can squeeze a trip to the gym into their busy schedules, West suggests circuit training using the weight machines. Rotating around exercises that use different muscle groups cuts down on the recovery time between sets.
The Mommy-to-Be
-- Expert Favorite: Prenatal Yoga
Pregnant women should never try to work out harder than they did before becoming pregnant and in general should look to low-impact, low-intensity forms of exercise such as walking, pregnant yoga, and swimming.
Into the second and third trimesters, women should choose exercises that support the abdomen and lower back because there will be a shift in her posture due to the extra weight, says Davis. "Seated and lying exercises, no heavy squats, and more walking, less running."
The Ex-Jock
-- Expert Favorite: Lower-Intensity Weight Lifting
Former athletes, even those who have been "on the bench" for a decade, do have an advantage over those who were always sedentary, says West. There will be some carry-over of their former fitness, but they're still going to have to start with the basics if they want to excel at sports again, he says: flexibility, cardiovascular training and resistance training.
"You can go back and lift again, but you're going to be working with less weight than you remember and you're going to need more recovery time than before," says Davis. As long as they build up in intensity slowly, the sky's the limit in terms of the kinds of exercise they can pursue.
The Generic Jogger in Need of a Boost
-- Expert Favorite: Weight Training
Those who jog quasi-regularly are usually in good cardiovascular shape, but they can be surprisingly low in muscle strength or flexibility, experts say. This makes casual runners a prime candidate for a little weight training to build up the muscles that support their running, such as those in the back and stomach. Especially after age 40, injuries from running will be muscular and skeletal, says Peter Walters, associate professor in the Applied Health Science Department at Wheaton College, so building up the muscles with strength training will make someone less likely to injure themselves during their weekly jog.
For casual runners who want a jumpstart, West recommends high-intensity interval training (HIT). It's running, only amped up: "sprint for 30 seconds and rest for 30-90 seconds and then repeat," he says. The same principle can be applied to biking or other kinds of aerobic exercise. Studies show that people who do this kind of high-intensity interval training boost their aerobic capacity more than those who exercise five times as long at a slower, steady pace.
The Retiree With Arthritis
-- Expert Favorite: Aqua-Aerobics in a Heated Pool
Low-intensity, low-impact exercises that don't require a lot of balance are key for those suffering from arthritis. This is why hands down the best exercise is working out in a heated pool with styrofoam dumbbells. On land, lifting weights can lead to strain or injury if they are dropped, and only work the muscles in one direction. Moving a Styrofoam dumbbell underwater provides resistance in every direction, while the warmth of a heated pool keeps the muscles and joints loose and less prone to injury, says West.
Copyright 2011 ABC News Radio
Stockbyte/Thinkstock(BOSTON) -- There hasn't been much research on whether physical activity is important for people with prostate cancer. But now a study from the Harvard School of Public Health of nearly 1,500 patients diagnosed with prostate cancer that had not spread, suggests that brisk walking could "delay or even prevent progression" of prostate cancer.
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