Knees brushing/hitting during speed work

Today during my first speed workout of the year, I noticed for most of the reps that my knees kept brushing against each other, it was really annoying and concerned me. I’ve been running long distance for the last 12 years and this doesn’t normally occur. I’ll add that I haven’t been strength training for the last few months (bad I know). A quick Google gave me some ideas but wanted to ask here if anyone has any advice on why it might’ve happened or how to fix/try to solve? Thanks!👟💙