Is it important to improve flexibility? If so, why?

The 3 essential elements of a fitness program are strength, cardio, and flexibility. The last is the part most often neglected. Flexibility training increases your range of movement, which affects posture, physical and mental relaxation, muscle tension and soreness, and—perhaps most important—risk of injury. Increasing your flexibility can help your other physical fitness elements too. For example, tight hip joints can reduce your running efficiency and increase your chance of injury. There are many ways to improve your flexibility, including yoga, foam rolling, dynamic warm-up before your workout, and static stretching post-workout. A proper warm-up and cool-down with stretching is important every time you exercise, but try to make time for flexibility-specific training at least 2–3 times per week.