Cable One-Arm Triceps Extension Bodybuilding Exercises Training Methods Weight loss by admin - 9 June 20179 June 20170 Cable One-Arm Triceps Extension Target and strengthen your arms with the cable one-arm tricep extention.The Move: Cable One-Arm Triceps ExtensionWhy: Isolating the triceps one arm at a time with cable extensions helps concentrate on the triceps muscle and ensures continuous muscle tension throughout entire exercise.How: With your right hand, grab a single handle attached to the high cable pulley. Stand directly in front of weight stack. Now pull the weight down so that your upper arm and elbow are locked into the side of your body.