En español | Fitness should be simple, convenient and not cost an arm and a leg. Even the most earnest of good exercise intentions will fizzle quickly if the gym is too distant or you can't afford the fees, if you lack the high-tech gear you're convinced you need, or if you don't know how to craft a workout that yields meaningful results. Never mind the added obstacle of venturing out in nasty winter weather to burn a few calories.

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To that end, here's an exercise regimen you can do at home, in minimal space and with next to no equipment. This probably won't set you up to win a triathlon, but it will help you attain and maintain sound fitness for healthful everyday living. Of course, it's a good idea to talk to your doctor before starting a new exercise regimen.

People age 50 and older need three things from their workout plan: aerobic conditioning, muscle strength and endurance, and core fitness, says Walter R. Thompson, Ph.D., regents professor in the Department of Kinesiology & Health at Georgia State University in Atlanta. Aerobic fitness is a key to heart health and helps the body move oxygen to tissues where it is needed — including the brain. Muscle strength and endurance help protect bones from osteoporosis and injuries. They also help prevent falls and lower the risk of strain from everyday tasks, such as lifting grandkids and shopping bags. And we need a strong, stable core to support everything our arms and legs do.

Aerobic Exercise

Aerobic conditioning "can be as simple as putting on some music or turning on the TV and marching in place," says Lynn Millar, Ph.D., a professor of physical therapy at Andrews University, in Berrien Springs, Mich., and a spokeswoman for the American College of Sports Medicine. If your space and fitness level allow it, you could jump rope, do jumping jacks, jog in place, hike up and down stairs or bounce on a mini trampoline.

The key is to work hard enough to get your heart rate up and keep it elevated for at least 10 minutes. More is better: Shoot for 20 to 30 minutes when starting out. Learn your target heart rate. 

Strength Training

For leg strength and endurance Millar recommends "wall sits," which entail putting your back against a wall, feet on the floor and knees bent at a 90-degree angle. For added comfort, do this with a stability ball bracing your lower back. Hold for 15 seconds; repeat three times. (Once that gets easy, try 30-second holds.) To make the exercise more dynamic, you can rise up and down, back still against the wall, from that "seated" position; start with three sets of 10 repetitions.

For a whole range of strength training exercise, spend a few bucks on an exercise band, says Thompson. The bands, made of a strong, elastic, balloon-like material, come in various tensile strengths and allow you to do everything from bicep curls and shoulder presses to rowing-like motions (for back and triceps muscles). All you need is something — like your foot, a banister or bed post — to anchor one end of the band while you pull, push or otherwise move the other end. "It's like weightlifting," Thompson says, "without getting under a bunch of weights."

Good endurance exercises, he adds, include push-ups and curl-ups. "You're not trying to create a lot of resistance," Thompson notes. The goal is to condition your muscle to work longer without tiring.  

If you can't do standard push-ups, try them with your knees on the floor. If that's too hard, do them against a wall while standing. However you do them, keep your back straight and your torso tight.

Curl-ups are like sit-ups (see description below) but should be done slowly, with arms at your side — not behind your head — and palms touching the floor. Flatten your lower back and come up enough to raise your shoulder blades off the floor before lowering slowly back down.

Next: Build your core strength. >>