Should I keep my knees locked or slightly bent?

Keep a very slight micro-bend in the knees to protect the joint, but avoid significant bending which turns the movement into a squat variation.

How does foot placement affect the exercise?

A neutral stance targets the entire calf, while pointing toes slightly inward emphasizes the outer head and pointing them outward emphasizes the inner head.

Is this better than standing calf raises with a barbell?

The machine provides internal stability which allows you to focus purely on the calf contraction without needing to balance the load manually.

Hack Machine Calf Raises: Technique and Tips

Master the Hackenschmitt machine calf raise with our guide on proper form, common mistakes, and how to maximize calf hypertrophy.

How to Perform

Position yourself in the hack squat machine with your shoulders firmly against the pads and your back flat against the backrest.
Place the balls of your feet on the lower edge of the platform so your heels hang off the edge freely.
Disengage the safety catches and fully extend your legs without locking your knees to take the weight.
Lower your heels as far as possible toward the floor until you feel a deep stretch in your calves.
Drive through the balls of your feet to raise your heels as high as possible, pausing for a moment at the peak contraction.
Control the weight as you return to the starting stretched position to complete the repetition.
Engage the safety catches once you have completed your final set before stepping off the platform.

Common Mistakes

Bouncing at the bottom of the movement using momentum rather than muscle fiber.
Bending the knees significantly which shifts the focus away from the gastrocnemius.
Cutting the range of motion short by not fully lowering the heels.
Using a weight that is too heavy to allow for a full peak contraction at the top.

Muscles Worked

Primary movers

Calves

Stabilizers

Tibialis Anterior
Soleus

Related Guides

Calves · Legs