While it may be well past harvest time outside, it is prime harvest season for equipment at Zum. We have new items sprouting up left and right, one of which I am particularly excited to talk with you all about. It’s what we call the GHD, which is an abbreviation for Glute-Ham Developer (or Glute-Ham Destroyer for those with a more sinister mind!) While it looks a bit complicated, I assure you that it is a fairly simple–and extremely effective–piece of equipment [see figures below].
The name is a little bit of a misnomer, as the GHD is designed to primarily work the hamstrings and calf muscles–although, it is worth mentioning that it works the glutes, just not as much as the name would have you believe. By locking your heels in against the cushioned pegs, you are isolating the lower portion of your hamstring and upper portion of your calf. This is important because exercises like the straight leg deadlift or Romanian deadlift (RDL) tend to isolate the work in the upper portion of the hamstring muscles.
The real strength (excuse the pun) of this machine is its use across sports to prevent hamstring injuries with a high degree of success. A large study of 942 professional Danish soccer players had athletes progressively train their hamstrings for ten weeks doing eccentric hamstring curls (starting with 2 sets of 5 on week one, and finishing with 3 sets of 12-10-8 on week ten). They saw a 70% reduction in acute hamstring injuries and re-injuries. Think about that: a 70% reduction in injury is a huge result. If you like to run, jump, bicycle, or play basketball, soccer, or any field sport, you really need to be doing this exercise. Check out the images below for a quick rundown on how to perform these movements, and then give it a try (But please, warm up first. It’s not a smart idea to do a hamstring curl on this piece of equipment cold!)