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  7. Jab Cross Left Hook Uppercut Combo

Exercise guide

Jab Cross Left Hook Uppercut Combo

  • Intermediate
  • Compound
  • Rep-based
  • Cardio

This high-intensity striking combination builds explosive power, rotational core strength, and cardiovascular endurance by engaging the entire kinetic chain from the feet to the fists.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Jab Cross Left Hook Uppercut Combo demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Calves
  • Obliques
  • Quadriceps

Secondary

  • Biceps
  • Forearms
  • Serratus anterior

Equipment

  • Body weight

Setup

  1. Assume a standard boxing stance with your lead foot forward and rear foot back, knees slightly bent.
  2. Keep your hands up by your chin, elbows tucked into your ribs, and chin slightly tucked.
  3. Distribute your weight evenly on the balls of your feet to allow for quick rotation.
  4. For this combo, start in an Orthodox stance (left foot forward) then switch to Southpaw halfway through your set.

How to do it

  1. Throw a Jab (lead hand) by extending your arm straight out, rotating the fist palm-down, then snapping it back to your face.
  2. Follow with a Cross (rear hand) by rotating your rear hip and foot forward while extending the rear arm fully; exhale sharply on impact.
  3. Transition into a Lead Hook by pivoting your lead foot and hips, swinging the lead arm horizontally with the elbow locked at a 90-degree angle.
  4. Finish with a Rear Uppercut by dipping your rear shoulder and driving the fist upward through the target, using your legs and core for vertical power.

Form checklist

  • Keep the non-punching hand glued to your face for protection at all times.
  • Pivot your feet and hips with every punch to generate power from the ground up rather than just the arms.
  • Maintain a slight bend in the knees to stay balanced and mobile.
  • Retract each punch back to the starting 'guard' position immediately after extension.

Pro tips

  • Focus on the 'snap'—the retraction of the punch should be faster than the extension to maximize muscle fiber recruitment.
  • Visualize the rotation as a whip starting from your feet; your fist is merely the end of the whip delivering the energy.
  • Keep your shoulders relaxed between strikes to avoid premature fatigue and maintain hand speed.

Make it harder

  • Add a 'slip' (lateral head movement) or a 'roll' (ducking under a hook) after the final uppercut to integrate defensive footwork.
  • Hold light dumbbells (1-2 lbs) to increase the demand on the deltoids and core stabilizers.

Frequently asked

What muscles does the jab cross left hook uppercut combo work?
The jab cross left hook uppercut combo primarily targets the abs, calves, obliques, and quadriceps, and also works the biceps, forearms, and serratus anterior as secondary muscles.
What equipment do you need for the jab cross left hook uppercut combo?
The jab cross left hook uppercut combo requires no equipment — just your body weight.
Is the jab cross left hook uppercut combo good for beginners?
The jab cross left hook uppercut combo is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • Cross Left Uppercut Cross Left Hook ComboIntermediate · abs, biceps, calves, deltoids, obliques, pectorals, and quadriceps
  • Marching On Spot Shoulders RotationBeginner · abs, calves, deltoids, glutes, obliques, pectorals, and quadriceps
  • Alternate Side Step Jump Side BendIntermediate · abs, calves, obliques, and quadriceps
  • Assault RunIntermediate · calves, glutes, hamstrings, and quadriceps

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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