Many people do aerobic training for endurance and resistance training for strength – but neglect flexibility training. The American Council on Exercise reports that flexibility training is considered an important part of a fitness program. Flexibility training allows greater freedom of movement and improved posture, increases physical and mental relaxation, releases muscle tension and soreness and reduces your risk of injury.
As with cardiovascular endurance and muscle strength, flexibility improves with regular training. Ideally, you should spend at least 30 minutes, three times per week, on flexibility training.