All great questions. I’m not exactly sure what caused it. I did go off the track a few times but it wasn’t major. I would guess that repetitive normal driving caused the bruising (combined with being really out of shape). Bruising is only on my left side. The bruising is where all the pressure was being created from the tight seat + rib protector (the previous seat was so tight I had trouble breathing in corners). The last time I drove was very painful and I was inflating my lungs and holding my breath through left handers to try and compensate for the pain.
Thanks in advance for any experience you can share.