Like foam rollers, massage balls work on the myofascial system. They reduce muscle tension and improve blood flow. This, in turn, aids injury prevention and rehabilitation. Massage balls are ideal for knots. They're very useful tight areas that can't always be worked with a foam roller. By targeting trigger points, spikey balls and massage balls can reduce pain levels. So instead of feeling tight, you can support your body's recovery following exercise, injury or even sitting at a desk all day.