The first baby boomers have turned 60, an age once linked with rocking chairs, reading glasses and rheumatism. This new wave of seniors is more likely to join in fitness classes, yoga and weight training than shuffleboard, with the hopes of staying healthy well into old age.

Where their parents may have focused on surviving into old age, boomers have shifted their emphasis to quality of life: how to remain independent in old age by not only preventing disease, but also maintaining vitality and function.

Americans 55 and older now make up a quarter of all health club members, according to a 2005 survey by American Sports Data (ASD), a marketing research firm. The number of 55-plus fitness buffs rose by a third from 1998 to 2004. That made them the fastest-growing age group in that survey. Over the same span, the number of 18 to 34 year olds who took part in a fitness activity at least twice a week didn’t grow at all.

So just who is slowing down?

The baby boomers “are definitely a group looking to redefine what is a senior citizen,” says Diane Fields, an International Sports Sciences Association master trainer. “Not only do they expect to live into their 80s or 90s, but they are expecting to be independent. And baby boomers view exercise as key to achieving longevity and maintaining wellness.”

According to the American Geriatrics Society (AGS), a person who is 65 today can expect to live 16 more years. Someone who is 75 today can expect to live until 85, and a person who is 85 can expect to live until 91. Most of adults in their 70s and 80s can also expect to be able to live independently for at least half of their remaining years.

Downward spiral

As we age, our bodies naturally change. We lose about one percent of muscle mass a year starting in our 40s, for instance. Our bodies’ ability to use oxygen while we work out also drops by about one percent a year after age 20. Bone density? Maximum heart rate? Metabolic rate? Down, down, down.

“For many years, it was thought that these were the inevitable consequences of aging,” says William Evans, PhD, director of the Nutrition, Metabolism and Exercise Laboratory at the University of Arkansas for Medical Sciences. “But the more we look at it, we find that these biomarkers are modifiable. Most of the factors that we think of as biomarkers for aging are actually biomarkers for how we live.”

The aging process depends on a combination of genetics and environment, the AGS says. And each person ages differently. There is no set “age” for a particular body system to change, but rather a range of ages. Body systems age at different rates. Some people may have problems with arthritis, the AGS says, but have a heart or kidneys in excellent shape.

A balanced diet and regular exercise are important to healthy aging. An inactive lifestyle can lead to some of the health problems associated with aging. A person’s percentage of body fat doubles between age 25 and 75. When you start weight or resistance training, your muscle mass can stay the same or even rise, and the increase in total body fat may be prevented or reversed. Bone density and metabolic rate go up, too. Aerobic exercise can slow the drop in your body’s peak oxygen use and heart rate.

Strengthen your routine

Like any age group, baby boomers’ exercise routines depend on their fitness goals and their health. For the average healthy adult, the American College of Sports Medicine recommends 30 minutes of moderate exercise three to four days a week. This can be broken up into several 10-minute segments. (Moderate exercise is activity that raises your heart rate to 55 to 60 percent of your maximum heart rate.) To lose weight, you’ll need to commit more that 30 minutes a day. It takes about 60 minutes of exercise on most days to burn enough calories.

According to the Baby Boomer Report, a survey sponsored by retirement community developer Del Webb, boomers most prefer walking, bicycling and swimming. Those activities are mainly aerobic. Only 24 percent expect to pursue strength training. That’s a mistake, experts say.

“You can argue that as one gets older,

[strength training] exercises are more important [than aerobic exercise],” says Cedric X. Bryant, PhD, chief science officer for the American Council on Exercise. “Muscular fitness allows you to participate in those activities that help you maintain cardiovascular functioning.”

You should aim for two days a week of strength training, with a program of eight to 10 exercises repeated 10 to 15 times each. After following a regular weight workout for three to six months, your strength should increase by 10 to 30 percent, the AGS says.

Strength training gear can range from costly resistance machines to free weights to common household items.

Flexibility is another aspect of fitness that’s especially important for older adults, the AGS says. Stretching exercises can improve flexibility. Add specific stretches to your workout or follow an exercise program that includes stretching. You should stretch before your workout, but after a gentle warm-up, or stretch after your workout.

Build over time

No matter their motives, Dr. Bryant stresses baby boomers should build over time to the recommended levels of activity. “Doing too much too soon only makes people discouraged or, worst case, results in injury,” he says.

Ligaments, joints, tendons and the spine weaken with age, just like muscles. But although a muscle pull can heal, skeletal injuries can linger and become long-term problems. That’s one reason for the popularity of gentler, mind-body activities. From 1998 to 2004, participation in Pilates—a series of controlled movements that is part yoga, part dance and part calisthenics—grew more than 500 percent, says ASD. Yoga and tai chi, a form of gentle, prescribed movements, rose by more than 100 percent.

Despite the risk for injuries, the benefits of exercise far outweigh the negatives.

20 benefits of exercise

Studies have proven exercise is good for you, particularly as you age. Here are just some of the effects of exercise:

  • Helps control body weight
  • Lowers LDL (“bad”) cholesterol
  • Raises HDL (“good”) cholesterol
  • Lowers anxiety
  • Maintains or improves muscle mass and strength
  • Maintains or improves blood flow
  • Maintains or improves blood oxygen levels
  • Maintains or improves aerobic endurance
  • Maintains or improves metabolism
  • Maintains or improves balance
  • Maintains or improves joint function and tendon strength
  • Maintains or lowers blood pressure
  • Improves self-confidence and self-esteem
  • Can improve flexibility
  • Helps head off diabetes
  • Helps head off osteoporosis
  • Helps head off certain types of cancer, notably colon and breast cancers
  • Helps head off depression
  • Helps improve sleep
  • Lessens insomnia, migraines and mood swings among menopausal women

Sources: American Heart Association, National Cancer Institute, Georgia State University Department of Kinesiology and Health, Medicine and Science in Sports and Exercise