4. Think fun and variety

By nature, humans need change and variety to stay motivated . We also need to have fun — even while we’re working hard. Do both!

Listen to your inner voice when choosing the best workout for you, says Fowler.

Workout variety also challenges your body in unique ways, which may introduce you to new muscle groups you didn’t even know you had. Consider disciplines that give you more bang for your buck, suggests Haberstro. Ta’i chi and yoga, for example, serve dual purposes as mental therapy and physical activity. Or try a workout DVD to help you shake up your routine.