Sit like a happy dog - with your tail up in the air
Sad or naughty dogs tuck their pelvis rounding their lower backs so their tail tucks underneath them - that's how most of us sit these days - like sad naughty pups with our tail between our legs.
This puts our pelvis into a posterior pelvic tilt, rounding out our lumbar spine into a C-shaped kyphosis. However, our lumbar spine (lower back) is designed to be positioned in the opposite way, in what's called a lordosis.
So next time and every time you sit down practice sitting like a happy dog!
Stick the bum backwards, hinging from the hips. Keep the chest high and the lower back curved inwards rather than rounding outwards. Bend at the hips rather than bending or rounding the lower back.