Hi all,
I've been having my first rides on my recumbent and the posture which the seat puts my back in is quite different. On a diamond frame, I would straighten the back quite a bit in order to protect it while pedalling hard. Now when lying down, the back is worryingly "passive". Aren't we supposed to engage the back lower back muscles to protect it? Foremost I'm worried about my pelvis rounding up in order to fit the anatomical shape of the hardshell seat.

Thanks in beforehand!