What Happens During a Kettlebell Swing?

What Happens During a Kettlebell Swing?

Ever wondered what exactly happens during a kettlebell swing?

What muscles do what, and why? Following is the analyses of a double arm kettlebell swing with an insert.


From back swing to up phase

Hip extension
  • Gluteus Maximus pulls the top of pelvis up
  • Hamstrings pull on bottom of the pelvis

Hip extensors


Knee extension
  • Quads extend the knee


Prevent ankle flexion (Plantar flexion)
  • Calfs pull to stop the knees from coming forward


Remain erect
  • Spinal erectors stop the spine from falling into flexion, and keep it erect


Protect shoulders
  • Latissimus dorsi pull the ball into the socket to protect the shoulders


Pull shoulders back
  • Middle and lower trapezius retract and pull the shoulders back
  • Rhomboids major and minor retract the scapula


Elbow extension
  • Triceps keep the elbow extended

Whether you need to keep the elbows extended depends on the trajectory of the kettlebell, out or up?


Finger flexion
  • Muscles in the anterior compartment of the forearm keep the fingers flexed to maintain a hold on the kettlebell handle

A tight grip that does not relax at the top of the swing will create tight forearms, or injury with high and repetitive volume.



From floating phase to back swing


Hip flexion
  • The hip flexors pull the pelvis down

Note, that saying hip flexors is just an easy way to avoid naming all the muscles that are within this large muscle group: Psoas major, Iliacus muscle, Rectus femoris, Sartorius, Tensor fasciae latae, Pectineus, Adductor longus, Adductor brevis, Gracilis.


Knee flexion
  • The hamstrings flex the knee joint

Note, there are more knee flexors, two of them are located at the front.


  • The hamstrings pull the hips further back and down to create an insert

The insert is the opposite of letting a pendulum complete, which is common cause for kettlebell bobbing with beginners.


All other points from the up phase apply, like: shoulder protection, arm extension etcetera. This is just the basics, take our online course, or buy our books to get the nitty gritty on the kettlebell swing.


Expand your mind, don’t get stuck with one swing, one way of doing things, know your goals, learn what’s safe, and use whatever you need to reach your goals. Take our online course today, or buy the book in electronic format, or paperback on Amazon.


Your feedback/questions below or on this Facebook post.


Why even care about muscles used?

  • Know what muscles should be recruited and when
  • One trains to reach goals; knowing what muscles are worked, allows programming towards reaching goals
  • Prevent injury
  • Provide correct cues to athletes

Leave a Comment

Shopping Basket