Stiff leg deadlift

I read that you shouldn't lock your knees but this demo from Dorian Yates it looks like he is, whats the correct way?

LINK

It would be good to get one of the training mods opinons on this, personally I use stiff legged deads on my leg day to work hamstrings. But I stand on a raised platform so I can go deeper, I lock my kness but don't stand vertical at the end of the movement, I stop short to keep the tension on

I went with locked as well, I was ok up till the 3rd set then I found for the last two I was struggling to get the weight down. Might try doing them before squats next time.

Jumped in the bath after training then almost fell down the bloody stairs I just had nothing left lol

I had a trial with them, just seemed like an injury waiting to happen.

I belive it's an effort to keep the stress on the hamstrings. I'd just stand up right.
 
If you've locked out the knees standing upright will make zip al difference to the stress applied to the hams.

You shouldn't lock your knees, you get better rom with a slight bend, if you need to do them off of a platform then your back can't be anywhere near straight.

teapot


You shouldn't lock your knees, you get better rom with a slight bend, if you need to do them off of a platform then your back can't be anywhere near straight.

Locking knee is fine. Technically the straighter the legs the greater ham recuritment not more, neither will you have greater ROM. 
 
As on standing on a platform I don't see the need but neither would I worry about the back being straight. I bit of a curve in the upper back and even the lower back will be fine, as long as you have adequate control. This is not somethinmg I would get a beginner to do but an experinced strong lifter with a healthy back should be able to lift in a somewhat rounded back and be fine.