I have been recently trying to develop strength to do a Glute Ham raise by doing the eccentric phase to a point where I can get myself back up without help.
I don’t have a glute-ham machine, so I put my ankles underneath my bed and use a pillow under my knees for cushioning.
When my knees are extended somewhere beyond 90 degrees, there is a great deal of pressure on my knee caps.
Does anyone have any ideas on how I could protect my knees while doing this exercise?
Place more padding under your knees.
I have a similar issue when doing GHRs off the seated calf machine. If I don’t position myself right there is more pressure on the knee than should be. The angle of the lower leg will play a role in how much pain you experience.
I dont like putting my knees under undue stress. There are other options for building glute/hamstrings.
Barbell hip thrusts thrash the glutes.
Deadlifting with an emphasis keeping the legs straight (something like a RDL) will do the hamstrings.
Sprinting can complement this kind of work well too.
just a suggestion based on something i read somewhere but maybe a foam roller might work? obviously depends on the height the bed sits off the ground, and i guess you’d put it either just above or just below your knee
Your issue is that a) you need padding under your knees, and b) that the natural glute-ham raise is an advanced movement which places a great deal of stress onto the connective structure of the knee. Work slowly into it- or find a gym which has a glute-ham raise machine!
The machine is much easier and, at least in my experience, is restorative for the knees.
Either that or do what the people suggested- stiff legs, rdls, good mornings, sprinting, etc.
Blasta,
I had the same problem, someone on here suggested the following which worked for me;
-Use the lying Hamstring curl machine, set the pad so it’s extended as far as it can go (the pad is what you will use to grip your calves against)- set the pin in the weight stack so it has the maximum weight to act as a counter-balance
-place a bosu ball under your knees with the flat side on the ground, you will need to adjust your position until it feels right
what I do is start from the ground with the combination of a push up and some momentum from my hamstrings, I then perform the de-celeration back to the ground as slowly as possible, after a few weeks I can now really control the movement on the way down and my hamstrings kill me 
here’s a video: Glute Ham Raise Alternative - Phil Felice - YouTube
I hope this helps-
@Gerrard08: Thanks for the video. It helps a lot; points out what vigilanteavenger said.
@vigilanteavenger: That’s kind of what I had in mind, because the knee caps won’t be pressing against anything after the knees are extended beyond a certain angle. I’ve noticed the glute ham machine is built to get the same effect.
@yarni: Those are good ideas, but I forgot to mention I don’t have acces to a gym. All I have
are sandbags, but thanks: I might try to adapt some of those exercises if I can’t make the GHR work.
Thanks guys!