Russian twists are a simple abdominal exercise that work the core, shoulders, and hips. They are typically performed in repetitive sets and involve a twisting motion focused around the abdomen. The exercise can help build strength in the upper torso, which may help in sports such as tennis, swimming, baseball and football, track & field, hockey, golf, lacrosse, or boxing.

To perform the Russian twist, one sits on the floor and bends both knees while feet are kept together and held slightly above the ground (or put under a stable surface). Ideally, the torso is kept straight with the back kept off the ground at a 45-degree angle with arms held together away from the body in a straight fashion and hands kept locked together like a ball or one can hold a weight to increase the difficulty. There are also many variations of the Russian twist that can be used to intensify a workout routine, such as using a stability ball or with a barbell standing up.

The Russian twist is thought to be named after one of the exercises developed for Soviet soldiers during the Cold War, though its popularity today makes it a universal exercise. It is a great exercise to build core and shoulder strength, and athletes use it for rotational movement, which can be seen in sports.

In summary, Russian twists are a simple abdominal exercise that work the core, shoulders, and hips. They are typically performed in repetitive sets and involve a twisting motion focused around the abdomen. There are many variations of the Russian twist that can be used to intensify a workout routine.