The move might not be obvious from the name, but the kettlebell windmill is a fantastic exercise for your core. A skilled movement that requires flexibility and coordination, the kettlebell windmill improves hip mobility, back function and core strength.
To perform the move, stand with your feet hip-distance apart. Bend down to pick up the kettlebell from the floor using your left hand; use your hips to clean it up so it's extended above your shoulder. Keep the kettlebell straight over your shoulder as you hinge forward from your hips to touch your right foot with your left hand. Return to a stand to complete one repetition.
Primary Target: The Core
The windmill is considered a functional movement that targets multiple muscles, including your core. Both high and low windmill variations target the abdominal muscles of the rectus abdominis, which forms the front sheath of your abs, and the obliques at the sides of your waist.
A strong spine is integral to a powerful, stable core ,and it gets worked from multiple angles with the windmill. You experience rotation through the thoracic, or mid, spine and the lumbar, or low spine. This means your erector spinae, a grouping of muscles along the spine, and quadratus lumborum at the back of the abdominal wall, work hard.
Other Muscles Engaged
The hip flexor muscles, collectively known as the illiopsoas, also activate as you bend down. Your gluteus maximus engages to help you rise back up. Your upper back, particularly the trapezius muscle covering the back of shoulders, neck and upper back, activates as you twist slightly and maintain stability in the shoulder. The deltoids, which form a cap around your shoulder, also work during this stabilization.
Variations + Alternatives
Sometimes, the windmill is performed "low," where you hold the bell with your lower hand in front of your hip as you rise and lower. Instead of crossing the body, you lower the weighted arm to inside of the same leg. If you're holding the weight in the right hand, for example, you lower to inside the right leg.
The windmill isn't as rigorous as some other kettlebell exercises, such as the swing, but it requires absolute precision to perform properly and prevent injury. Like any new exercise, start with a light weight or none at all. Concentrate on engaging your abdominal and glute muscles as you stabilize to lower your torso and use their strength to help you rise up.