Element Glute / Ham Developer GHD51 A machine that tortures your glutes and hamstrings? Yes this is that machine! Great for developing strong glutes, low back, ham strings & abs. Functionally, it is one of the best hamstring exercises because it trains your hamstring at both joints (knee and hip). When you run, jump or squat, your hamstrings are challenged at both joints. Adjustable horizontally. Levelers to protect floors and ensure a balanced station.