Synergists: Hamstrings (Biceps Femoris, Semimembranosus, Semitendinosus), Adductor Magnus
Important stabilizers: Erector Spinae
Grasp a barbell using a shoulder-width pronated (overhand) grip or a mixed grip.
Keeping your back straight, head up, and hips low, lift the barbell into a standing position.
Flex your knees a little.
Keeping your back straight and your knees slightly flexed (stiff), inhale as you push your hips backward and slowly lower the barbell down the front of your legs. Descend until you feel a mild stretch in your hamstrings.
Exhale as you pull the barbell back up to the starting position by pushing your hips forward.
Comments and tips
Keep your knees stiff, your back and arms straight, and your head up.
Keep the barbell close to your body to improve mechanical leverage.
If you can lower the barbell low enough for it to touch the floor, perform the exercise on an elevated platform.
Contrary to what some people think, the barbell straight back stiff leg deadlift targets your gluteus maximus and not your hamstrings. The reason is that by flexing your knees even just a little, you place your hamstrings in a state of mechanical disadvantage, thus forcing your gluteus maximus to work the hardest during hip extension. If you want to target your hamstrings, keep your legs straight (in which case the barbell straight back stiff leg deadlift will become the barbell straight back straight leg deadlift).