What is the differnce between Straight leg deadlifts and normal deadlifts?

I keep on hearing how sldls are good for legs, and normal deadlifts are good for your lower back, is there a differnce between the two? Also, if here isnt a differnce should I do them on my back day or on my leg day?

Some light reading

http://www.discussbodybuilding.com/a_question_about_deadlifts/m_128889/tm.htm

My home away from DBB

yea ive been kinda confused about that too i mean i would think its the other way around cause with deadlifts u use ur legs to do a sort of squat movement and only get the weight up with ur back half way where as with straight legged dead lifts your only using ur back, its just like a hyperextension which is a back exercise. so i really dont know why its that way but i do know that deadlifts defenetly do work the lower back well and sldl work the hamstrings and lower back.

Duke of the Emancipation Detoxification

Back or leg day?... the eternal conundrum

Properly done, deadlifts are supposed to stimulate your glutes and hamstrings the most. But the truth of the matter is, DLs are one of the only exercises that can be turned into a near total-body workout. With a little shrug thrown in at the top, there simply is no greater upper back/trap stimulating movement. And few rowing movements get your core working like DLs do.

That said, it's really up to you. When I do incorporate DLs into a workout, I do them on days when I feel I have the most energy left to tackle them with passion. For example, if I kill myself on leg day, I'm not going to be too enthusiastic about throwing a tactical nuke like DLs on top of that. Better to save them for back day.

Just remember, they produce so much spillover stimulus, that it really doesn't matter what day you do them on -you're going to end up hitting something before it was fully recovered. All told, I still think this is a good thing.

My home away from DBB

They both work your hamstrings although regular deadlifts also work the quads as well as the glutes. If your trying to focus on building your hamstrings either stiff leg deads or goodmorning r probably the best way to go. I prefer olympic style squats to regular deadlifts but they both should be done. 

They are both great exercises. If you want to work your hams more, don't have your knees bent as much. Keep your legs nearly straight ofcourse not locking them out.
 
I would switch them every now and then or from cycle to cycle for added stimulis

"if you like animals with cages, then you must be gay"

o damn ive always locked out on sldl.  whats the difference between a good morning and a sldl?

Duke of the Emancipation Detoxification

 
The first is a good morning and the second is a stiff leg deadlift (SLDL). As you can see it is the same general movement focusing on the glutes and hamstrings. The SLDL is much safer simply because the weight is held below the body and can be easily set down, as opposed to the good morning where the weight rests on the shoulders and runs the risk of rolling up onto the neck.
 
For safety reasons I would highly recommend the SLDL.

Add me on facebook!

U shouln't go all the way down like the guy in those pictures or have your head down. Doing that  stretches the ligaments in your lower back. You should lower your self no more then 80-85 degrees anything more then that puts undue burden on your spinal erectors.

that seems stupid. its the exact same movement except with good morning u can hurt urself, i think ill just stick with the sldl's.

Their both good exercises and both equally dangerous. People tend to go further down in the sldl thus putting their back at major risk for injury.

There are many other good exercises that hit your hamstrings like a good morning or sldl. My personal favorite is the weighted hyperextention.
 

Add me on facebook!

i always thought that was just back but i guess it is pretty much the same movement.

I agree to not going down all the way.  I go down until the bar is a little bit under the knees.  anything more than this will involve the lower back until the bar gets up around the knee area. i wouldnt lock out either, a slight bend of the knees would be great.  also remember to keep the head up.

an SLDL u can do with legs slightly bent and u use more low bac and hams. Regular deads u use more muscles then just ur legs and low back.