Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Engage your core, keeping your lower back pressed against the floor. Drive your attached knee towards your chest, flexing your hip until your thigh is perpendicular to the floor. Briefly pause to contract your hip flexors, then slowly lower your leg back to the starting position, maintaining a flat back.
Focus on keeping your ribs down and braced to prevent lower back arching and ensure stability throughout the movement. Maintain a flat lower back throughout the exercise by consciously engaging your core muscles and avoiding any rocking or shifting. As you drive your knee towards your chest, visualize pulling your thigh directly upward, maximizing the contraction of your hip flexors. Control the lowering phase of the exercise, resisting gravity to build strength and prevent momentum from compromising your form, and feel the engagement in your hip flexors.
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