Lunges are a great exercise if done correctly, but can cause knee problems if not performed properly. Lunging is a movement that involves bending at the waist while lifting both legs off the ground. This type of exercise is commonly used in martial arts and is often incorporated into fitness routines. Lunges have been shown to strengthen the quadriceps muscle group, which helps prevent injuries and strengthens the muscles around the knee joint. However, they can also lead to knee pain if not executed correctly.