I keep hearing about exercise programs to train the "core" muscles. What are these and what works best?

The two main core muscles are the transversus abdominis musdcle and the multifidus muscle (a deep back muscle). It's thought that these muscles work together to help stabilize the
spine. Improving core muscle strength is designed to improve athletic performance and prevent injury.

There are many ideas about how to strengthen the core muscles. One type of exercise called Pilates (named after Joseph Pilates in the early 1920s) is very popular. Pilates exercise can be done as a floor exercise without any equipment, but more often uses a device called a transformer to help condition muscles and improve core
strength.

The medicine ball toss (a weighted ball) is also used by many people. You can toss and catch the ball alone or toss it back and forth with a partner while sitting or standing side by side. There are many ways to use the ball whether working alone or together.

Even though core training or strengthening is widely used, there isn't a lot of data to show how or when it works best. Research is needed to help identify the best exercise
strategy. Scientists are working on finding out what's "normal" core strength in everyday people of all ages compared to athletes. Studies comparing uninjured versus injured
players is another area of interest.