Back Squat

I did "true crossfit warmup," which entailed:
2 rounds of:
- 5 air squats
- 5 pushups
- 5 situps
1 round of 10 of all above exercises; did these between the sets of 5 reps
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back squat, 5 rounds of 5 reps
- supposed to shoot for 85% of 1rm, but I was nowhere near this
- my legs were really shaky and sore from yesterday's workout,
- everything felt really heavy (1RM was 110 so 85% would have been like 90lbs)
- did 2 sets of 5 on 45 lb bar, then went up to 55lb, did 5 reps once
- 55 lbs felt really heavy because my legs were so sore and weak
- then did some more air squats to work on form and warm up more
- did 35 lb bar, 2 sets of 5
- tried to stretch really well to ease some of muscle tension