u/Visplay

I started using the adductor machine a couple months ago and I noticed stretch marks? near my left inner thigh. I've never gotten stretch marks before so I'm not sure if they are stretch marks or not. They're reddish in color and the skin feels tender and slightly sunken (they don't hurt or anything). Should I pause this exercise? Im seeing more of these marks compared to a month ago

How is power modeling done in industry and/or research? I feel like performance modeling is easy to understand with needing to model cycle behavior, but power seems much more difficult to estimate with abstract representations?