Now this i did today and an exercise i never see much. This exercise can really improve your bench press because it strongly works the medial and lateral heads of the tricep...a real boost for benching...
execution is :
1 grasp a Dumbell in 1 hand and roll back onto a flat bench.
2 Extend your working arm straight over your chest
3 Brace your working arm Biceps with your non-working hand, then bend your elbow untill the DB touches your chest(keeping your upper arm in a stable .. static position.
once you finish reps with the working arm swap over arms...and ENJOY:
The picture below does not show the working arm braced but i find it better.
FANTASTIC EXERCISE......3 SETS AT THE END OF THE WORKOUT.