Try to keep your legs as straight as possible and let your hands dangle or place blocks under them if they don't reach the floor.

Billy Rogers

Pixels Eliana Fairytale

Forward Bend

Some teachers will tell you it's alright to bend your knees in this pose if your low back hurts. That's true,

Another option for a standing forward fold is to take your legs out wide.Keeping the legs at about a 90-degree angle allows for a good hamstring stretch.

Pixels Marta Wave:

Standing Legged Forward Bend

For full hamstring effects, concentrate on keeping your weight in the balls of your feet just as much as in the heels.

Try instead to release the heels down but have the feet in a position where the heels hover off the floor. Downward dog is an awesome pose for many parts of your body.

DOWNWARD FACING DOG

Janu sirsasana, it's easier to get a hamstring stretch than it is with both legs straight. If forward bends hurt your back, loop a strap around your flexed foot.

JANU SHIRSHASANA

Pixels Elina Fairytale

Imagining the pelvis as a bowl slowly tipping forward helps encourage the correct rotation of the torso over the legs.

UTTANASANA

It"s important to keep the feet strongly flexed throughout and to engage your thighs as much a possible.

Even though your leg might not look as straight, a microbend, which is a slight softening, at the knee is a safer position for your joint health.

PYRAMID POSE

Pixels Miriam Alonso

Standing split has much the same form as half moon (above), except both hips are pointing toward the floor. It doesn't matter how high your leg can go.

STANDING SPLIT