Exercise is required for maintaining muscle mass, but you cannot “just do it,” as fitness slogans state unless you have energy. Building energy first will allow you to begin exercises that strengthen muscle mass. If you are unfit, the activity you want to start with is walking because it works your leg, arm, and abdominal muscles. For maximum benefits, try varying your pace to challenge yourself without becoming fatigued. As you develop muscle mass, you will enjoy more immunity, energy, confidence, and protection of your joints.