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  5. Legs
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  7. Peterson Forward Side Step

Exercise guide

Peterson Forward Side Step

  • Intermediate
  • Compound
  • Rep-based
  • Hips
  • Lower legs

The Peterson Forward Side Step is a specialized unilateral movement designed to isolate the VMO (inner quadriceps) and improve knee stability by combining ankle dorsiflexion with terminal knee extension.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Peterson Forward Side Step demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Calves
  • Glutes
  • Quadriceps

Secondary

  • Adductors
  • Hamstrings
  • Hip flexors

Equipment

  • Body weight

Setup

  1. Stand with your working foot on a 4-6 inch step or elevated block.
  2. Position the working foot so the heel is free to lift or slightly elevated, with the non-working leg hanging off the side.
  3. Maintain an upright posture with your hands on your hips or held out for balance.

How to do it

  1. Inhale and slowly lower your non-working leg forward and slightly out to the side at a 45-degree angle.
  2. Allow the heel of the working foot to rise as you descend, keeping the weight on the ball of the foot to maximize VMO activation.
  3. Lightly touch the heel of the non-working foot to the floor without shifting any body weight onto it.
  4. Exhale and push through the ball of the working foot to return to the start, fully locking out the knee at the top.

Form checklist

  • Keep the working knee tracking directly over the second toe.
  • Maintain a vertical torso throughout the entire range of motion.
  • Ensure the non-working leg remains straight as it reaches for the floor.
  • Avoid 'bouncing' the heel off the ground; use a slow, controlled 3-second eccentric phase.

Pro tips

  • Focus on a hard contraction of the inner quad (VMO) at the very top of the movement.
  • Maintain a 'proud chest' to prevent the hips from hinging backward, which shifts tension away from the quads.

Make it harder

  • Increase the step height to 8-10 inches to demand greater range of motion and ankle mobility.
  • Hold a light dumbbell in the hand opposite the working leg to add load and challenge lateral stability.

Frequently asked

What muscles does the peterson forward side step work?
The peterson forward side step primarily targets the calves, glutes, and quadriceps, and also works the adductors, hamstrings, and hip flexors as secondary muscles.
What equipment do you need for the peterson forward side step?
The peterson forward side step requires no equipment — just your body weight.
Is the peterson forward side step good for beginners?
The peterson forward side step is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • Alternate Forward Step Arm SwingIntermediate · calves, glutes, and quadriceps
  • Arms Up Rotational Side StepIntermediate · calves, glutes, and quadriceps
  • Back Shuffle Side KickoutIntermediate · calves, glutes, hamstrings, and quadriceps
  • Barbell Band Assisted DeadliftIntermediate · calves, glutes, hamstrings, quadriceps, and trapezius

Train it with Crucible Fit.

Every movement in this library is in the app with video and instructions, ready for your own sessions on the days between Crucibles. Your first Crucible is on us.

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