Why is ballistic stretching no longer recommended for preparing the body for exercise?

It is still recommended and it is okay to stretch this way.

Ballistic stretching involves bouncing the body while stretching a muscle group past its current flexibility. For example, instead of reaching slowly and gradually extending your body towards your toes in a straddle stretch, you would bounce 4-5 times towards your toes. This can result in strained or torn muscles or ligaments.

Ballistic stretching is no longer recommended for preparing the body for exercise because it carries a higher risk of injury compared to other stretching methods. The bouncing motion and rapid movements involved in ballistic stretching can cause the muscle to stretch beyond its natural range of motion and lead to strains or tears in the muscles or ligaments. This type of stretching can also induce a reflex contraction in the muscles, which can further increase the risk of injury. Therefore, static stretching or dynamic stretching methods that involve controlled movements are generally considered safer and more effective for warming up the body before exercise.