Swap one workout for another. Lack of time tends to be a reason for not exercising. So instead of being overwhelmed thinking you need to add flexibility, strength training and other forms of exercise to your already busy schedule, maybe substitute a 30-minute yoga DVD for a bike ride once or twice a week.

Strength-train no matter what. Swimming, bike riding and similar workouts only challenge the cardiovascular system, says Garcia. Running, for instance, utilizes quads and hamstrings, but "your core will get weak," she says. Lifting weights or using machines will round out your workout.

You don't have to go to a gym, says DiMarco. "Use free weights while watching TV or between loads of laundry."

Try a variation of your type workout. If you're a runner, swim, Garcia says. Or jog in the pool. If you take yoga, try Pilates.

Challenge yourself. "I have clients all the time who say, 'I don't want to do such-and-such because I'm no good at it,'" Holland says. "I look at them and say, 'That's exactly why you're doing it.'"

If, then

Tyler Herrin, a certified strength and conditioning specialist, offers tips on how athletes in one sport can benefit from incorporating another into their workout.

If you're a runner

Do strength and resistance training by adding basic exercises like squats and traveling lunges, and working quads as well as ligaments and tendons around the knees. Plus, core exercises will strengthen your abs, lower back and hips. This will help manage posture, strengthen bones and help improve performance.

If you're a yogi

Strength-train by adding resistance exercises using weights, elastic bands or machines in a gym. This will allow you to become stronger and hold poses for longer periods of time.

If you're a swimmer

Get out of the pool and do dry-land training. Try doing such weight-bearing workouts as running, jumping, rowing, stair climbing. "Core strength, upper-body strength is key," Herrin says. They'll help increase your bone density as well as build up endurance, "which will help in the pool."

If you're a weightlifter

Incorporate a cardiovascular routine and increase flexibility by adding some running or swimming. Or perhaps take a yoga class. "Just doing weights won't strengthen your cardiovascular or respiratory system," he says. "Yoga is beneficial for flexibility and respiratory strength."