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  3. Exercises
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  5. Shoulders
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  7. Boxing Jab With Bag And Gloves

Exercise guide

Boxing Jab With Bag And Gloves

  • Intermediate
  • Compound
  • Rep-based
  • Lower arms
  • Shoulders
  • Upper arms
  • Waist

The jab is a fundamental long-range punch that builds shoulder endurance, core rotational power, and cardiovascular fitness. It emphasizes the lead deltoid, triceps, and obliques through a rapid, snapping extension used to control distance and setup power shots.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Boxing Jab With Bag And Gloves demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Biceps
  • Deltoids
  • Forearms
  • Serratus anterior

Secondary

  • Abs
  • Obliques
  • Triceps

Equipment

  • Body weight

Setup

  1. Stand with feet shoulder-width apart, then step your dominant foot back and turn slightly sideways (Orthodox: left foot forward; Southpaw: right foot forward).
  2. Keep your knees slightly bent with your weight distributed on the balls of your feet for agility.
  3. Raise your gloves to cheek level, elbows tucked into your ribs, and chin slightly tucked toward your chest.
  4. Position your lead hand slightly further forward than your rear hand, aligned with the center of the punching bag.

How to do it

  1. Rapidly extend your lead arm straight toward the target, rotating your fist so the palm faces down at the point of impact.
  2. Exhale sharply through your mouth as you punch, engaging your core and snapping your lead shoulder forward.
  3. Impact the bag with the two largest knuckles, ensuring your wrist remains straight and locked.
  4. Immediately snap the hand back to the starting guard position at your face as quickly as it went out.

Form checklist

  • Keep your rear hand glued to your chin for protection while the lead hand punches.
  • Avoid 'telegraphing' by not pulling your hand back or dropping your elbow before throwing the punch.
  • Ensure your lead shoulder rises slightly to shield your chin during the full extension.
  • Keep your elbow pointing down until the final moment of extension to maintain a direct path.

Pro tips

  • Think of the punch as a whip or snapping a towel; focus on speed and retraction rather than pushing the bag.
  • Pivot your lead foot slightly inward as you punch to transfer energy from the ground through your hips.
  • Maintain a 'soft' grip inside the glove until the moment of impact to save energy and increase hand speed.

Make it harder

  • Perform 'Double Jabs' by throwing two consecutive punches with the lead hand before returning to a full guard.
  • Incorporate a small step forward with your lead foot simultaneously with the punch to increase range and momentum.

Frequently asked

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

Related exercises

  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals
  • Alternate Front Kick In Place With Arm CirclesBeginner · abs, calves, deltoids, and pectorals
  • Aztec Push UpIntermediate · pectorals, serratus anterior, and triceps
  • Band Bent Over One Arm KickbackBeginner · biceps, lats, rhomboids, 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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