Sub for squats/lunges


I’ve finished FB30 round 3 and I was planning to start Abs round 2 next week. However the last 2 weeks I’ve had problems with varicose veins in my left leg and I’ve read squats/lunges are not good exercises to do. I will go see my Dr, but I’m expecting to get referred out to a specialist. Meanwhile, I want to keep going with FB. I still want to do Abs as my core is pretty weak, but does it have a lot of squats/lunges? Any substitutions I can do instead? Some days I could sub a Pilates type lower body workout, but what to do in a HIIT or cardio/strength routine if there’s squats or lunges?

I’m bummed I can’t keep working out as I was, I finally could keep up on squat jumps :(. But I need to listen to my body and do low impact/sub in different exercises for now