Jawbreaker

The jawbreaker exercise uses one dumbbell to work one arm at a time. It really isolates the triceps muscle as the upper arm is held in position using the other hand.

Teaching points

  • Lay on a bench on your back holding a dumbell in one hand.  
  • Start with the arm straight and hand pointing to the ceiling with the palm facing your feet.  
  • Support the lifting arm with the other hand around the upper arm if you prefer.  
  • Bend the elbow to lower the weight towards the opposite side of the jaw.  
  • When the weight reaches an inch or two above the jaw, straighten the elbow back to the starting position.  

Variations & progressions

  • Perform in a standing or sitting position, with the arm straight overhead.
  • Bend the elbow behind you so the elbow points to the ceiling (keep the upper arm still).  

Muscles worked

  • Triceps Brachii.  

Alternative exercises

  • Tricep extension using a resistance band.  
  • Overhead tricep extension using a resistance band.  
  • Tricep dip.  
  • Tricep kickbacks.  
  • French press.  
  • Tricep Press.  

Related injuries

  • Inflammation and rupture of the triceps tendon.