To do the lying L-fly, lie on your right side on a bench while placing your right hand on the floor for balance. With a small plate or very light dumbbell in your left hand, form a 90° angle at your left elbow. Then put your left elbow on your left oblique muscles (or hip, depending on your body structure). Lower the weight until your left forearm rests against your abs, then raise your left lower arm as far as possible. Always keep your left elbow against your side. Inhale on the descent, and exhale on the ascent. Finish the set, turn around, and then work your right side.
Do the exercise slowly—at least two seconds for the lifting phase and another two seconds for the lowering phase. And use a weight which permits you to perform at least 8 reps with no more than 5 lbs for a man, or half of that for a woman. Add weight very slowly. Depending on training experience, a man may need a year or more to build up to using just 10 lbs. This is
quite a lot of weight for this movement; and 15 lbs may be enough for even a very strong man. Never train shoulder external rotation to failure. Keep the very last rep in you. Never get to the point where you need to raise your elbow or roll backwards a little.
The lying L-fly can help your shoulders. But push it too much or too quickly, and you will irritate your shoulders. After a few months of consistent work on the lying L-fly you can progress to the standing L-fly, or even use both movements in a program—one work set of each per arm.
Standing L-FLy
Quote:
Stand alongside an incline bench. The top of the bench should be positioned at the height of your nipples. Bend at your knees or raise the height of the bench to achieve this positioning. With a small plate or very light dumbbell in your left hand, rest your left lower triceps on the top edge of the bench. Then place your right hand on the bench directly under the lower triceps of your left arm. Keep your left elbow bent at a right angle throughout the exercise.
The angle between the bench and your shoulders should be about 60°, and certainly less than 90°. Starting with your left hand pointing to the ceiling, slowly lower the plate or dumbbell to a little below the point where your forearm is parallel to the floor. At this point your left forearm will be down on the opposite side of the bench to where you are standing. Then slowly raise the weight to the upright position. Inhale on the descent, and exhale on the ascent. During each set you must maintain the initial setup that has the top edge of the bench level with your nipples.
Do not lift or lower your torso. When you have finished training your left side, change over and work your right side. The safety rules of the lying L-fly apply to the standing version: Use slow and controlled form, avoid low reps, do not change your elbow positioning or angle during a set, and do not work to total failure.
Source: McRobert, Stuart, The insider’s tell-all handbook on weight-training technique
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