Lead by example. If you want your boyfriend to be active, be active yourself. Do the activities you love to do, whether or not he is willing to join. Not only will you inspire him by your behavior, he might also see these activities as ways to spend time with you. Leading by example is a nag-free tool that works surprisingly well.

Express your concerns. If you are worried about his health or that you are becoming less compatible because of his inactivity, tell him these things in a frank but compassionate way. Don't wait until you have your sneakers on and he's ordered his fifth pizza this week to air your grievances. Bring it up in the course of a relaxed, tension-free conversation, when you are not feeling resentful about his lack of interest in exercise and he is not feeling pressured. If he is receptive and open and you are compassionate and kind, he is more likely to take your concerns to heart.

Create incentives. To jump-start your boyfriend, you might offer small incentives for "good behavior." If he agrees to go bowling with you and your friends, tell him you'll rent his favorite film and watch it together. If he spends an hour at the gym, offer to give him a massage afterward. He may need a little something to look forward to in order to dig his hiking boots out of the basement.

Help him explore options. Exercise shouldn't feel like work or a chore. It shouldn't feel like just another item on a very long to-do list. Exercise should be fun and invigorating and make your boyfriend feel good about himself. Help him identify the types of activity or exercise that are most fun for him. Warning: these may not be the same activities that you enjoy doing.

Support your beau in his chosen passion. If he's developed a thing for tennis, buy him a racket or new pair of shoes. If it's jogging, enter you both in a 5K race. If he loves swimming laps at the local Y, offer to sit poolside and hold his towel. Whether or not you have equal interest in the activity, show him that you support his interest.

Be realistic. There might be very good reasons why your boyfriend has a low activity level. Perhaps he is not sleeping eight hours night. Maybe a poor diet makes him want to curl up on the couch rather than bike through town. Work-related stress and long hours may make it difficult for him to be active. Or your boyfriend may be struggling with a chronic physical or mental illness. Lifestyle adjustments may need to be made in order for him to feel inspired to be more active, and although you can certainly support him in these adjustments, they are ultimately his to make.