Lie flat on a bench holding a dumbbell with a pronated (palms-forward or overhand) grip. Extend your arm straight above your shoulder. Keep your upper arm fixed and slowly bend your elbow to lower the dumbbell toward the side of your head. Pause briefly at the bottom when you feel a stretch in your triceps, then extend your elbow to lift the weight back to the starting position. Keep movements controlled and avoid flaring your elbow or using momentum.
Log your dumbbell pronate grip triceps extension sets in 1RM.fit and watch your estimated 1RM update automatically as you get stronger.