The rear delts are a stubborn body part for the majority of people. Front delts are easiest, followed by side delts, and after that rear delts. I always thought reverse flys were the most efficient method to develop this area, however I was incorrect. Here's a video that shows a better exercise to build your rear delts. He demonstrates an exercise I have actually never ever seen before, but the most crucial takeaway is WHEN to train the read delts.
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