Walter Thompson, PhD, professor of kinesiology and health at Georgia State University, asks, "How much television do you watch?"
During your shows, use resistance bands or walk in place. Or use Tivo so you can skip the commercials and see a one-hour show later in just 40 minutes, says James Hill, PhD, co-founder of the National Weight Control Registry: "That's 20 minutes right there." Better yet, turn off the TV and spend your newfound time working out.
If it's work that's sapping all your spare time, try exercising on the job. Close your office door and jump rope for 10 minutes, or walk in place, Thompson suggests.
Your exercise doesn't have to be a formal workout either. Try making small lifestyle changes that help you move more: take the stairs instead of the escalator, don't drive when you can walk, and get a pedometer and try to increase the number of steps you take throughout the day.
The U.S. Surgeon General recommends at least 150 minutes of aerobic activity per week, which may sound daunting but actually works out to a little over 20 minutes each day. The good news is that three 10-minute exercise sessions work just about as well as one 30-minute one and can be much easier to fit into your schedule.
People who exercise regularly "make it a habit," says Hill, who is director of the Center for Human Nutrition at the University of Colorado, Denver. "They haven't bought any more time during the day than anyone else. What we've done is prioritize it. We find time for things we value."
It may sound counterintuitive, but working out actually gives you more energy, says Marisa Brunett, a certified athletic trainer in Orlando, Fla. Once you get moving, your fatigue will likely disappear.
"You're getting the endorphins [feel-good hormones in your body] to release,” says Brunett. "And you're getting the circulation going -- as opposed to coming home and crashing on the couch."
It may help to work out in the morning before you get wiped out by a demanding workday, says kinesiologist Lynette Craft, PhD, assistant professor of preventive medicine at Northwestern University.
But if you're just not a morning person, don't worry. Brunett, who likes to work out in the middle or at the end of the day herself, recommends doing it whenever you feel best.
The answer is to multitask, experts say.
"Take the kids with you," says Hill. While they're swinging, you can walk around theplayground or backyard or jump rope. Walk the kids to school instead of driving them. During their soccer games or practices, walk briskly around the field.
Use your family time for active pursuit, Brunett suggests. Go biking with your kids, put up a badminton net in the yard, sign up as a family for "fun runs," or just walk around the neighborhood with your children. When the weather's bad, try active video games like Dance Dance Revolution, Wii Sport, and Wii Fit.
And remember that your fitness is good for your kids as well as you. "When mom or dad is more fit, has more energy, the whole family benefits,” says psychologist Christina Recascino, PhD.
"Exercise should be like sex," says sports physiologist Mike Bracko, EdD, FACSM. "You should want it and feel good about it before you do it. And it should feel good while you're doing it."
So how do you get there? First, find an activity you love. Think outside the box: try inline skating, dancing, or gardening. Join a sports league. Or, if you love music, try ballroom dancing. "There's an exercise for everyone," says Recascino. "It doesn't have to be onerous or unpleasant."
If it makes exercise more enjoyable for you, it's OK to watch TV or read while you're on the exercise bike or treadmill -- just don't forget to pedal or run.
Working out with a group also helps many people. "Not everybody's cut out to put on their iPod and go on a six-mile run by themselves," says Peter Nierman, MD, assistant professor of psychiatry at the University of Chicago.
To find a group, look through local sports publications or on the web. Or simply recruit several friends.
And, every once in a while, try something totally new. “Mix it up so you don't get bored,” says Brunett.
"There are people who really enjoy not moving," says Gerard Endress, fitness director of the Duke Diet & Fitness Center. They prefer to knit, read books, or watch TV. "I work with those people on, 'Can you walk in the mall?'" he says.
If it's sweating you don't like, you can get a good workout without perspiring excessively, Endress says.
You can work out indoors where it's air conditioned. You can swim so you won't notice any perspiration. Or, try a low-sweat activity like gentle types of yoga.
If exercise hurts your joints, try starting by exercising in water, recommends Brunett. The stronger your muscles get, the more they can support your joints and the less you'll hurt. If your physical limitations are more serious, check with your local sports medicine or rehabilitation clinic, or find an athletic trainer who can help you figure out exercises that are still safe and easy to do.
If you don't like to move because you’re uncomfortable with your weight, start with an activity that's less public, like using an exercise video at home. Walk with nonjudgmental friends in your neighborhood while wearing clothes that provide enough coverage that you feel comfortable.
And remember that gyms today are different. "You don't have the Spandex gyms as much," says Endress. Women-only places may be more comfortable.
Set small, attainable goals. Then you're more likely to feel like a success, not a failure, says Brunett. If you exercise for five minutes a day for a week, you'll feel good -- and be more likely to want to try 10 minutes a day the next week.
It also helps to keep a log and post it somewhere public -- even on Facebook. Craft calls it a "wall of encouragement." Friends and family can then say, "Hey, you did 15 minutes yesterday. Great job," she says. A log also helps you see if you're starting to fall off the wagon (or the treadmill).
Having an exercise buddy keeps you accountable as well, says Boston psychologist Eric Endlich, PhD, who works with patients who need motivation to diet and exercise. When you back out of a scheduled workout, you're letting down your buddy as well as yourself.
And look toward the future. It's harder to start exercising than to stick with it once you've got your momentum going, says David Coppel, PhD, a sports psychologist in Kirkland, Wash. "I bet you after two weeks of this," he says, "you'll feel really good."