Minor Injury - How to proceed?

Howdy,

I just started the Foundation series about two weeks ago, and was progressing through the mastery checks and the first few workouts. At this point I've been able to pass many of the mastery checks without much issue (except for RC1, which was horrible - hah!).

Here's my issue: after the mastery check workout last Friday (for SL3/MN3/SLS3), I did a gentle squat to stretch afterwards and had a horrible grinding sound in my left hip. I think it was just a minor strain of rectus femoris, and I'm not sure if it was directly from the workouts or if it was a freak thing from the stretching afterwards, since I've had some similar issues with this hip in the past (though it was probably a combination). My default reaction when something like this happens is to back off and let it rest, which I've done since Friday.

My question is this: how should I progress once the injury heals? I think it'll only take a week or two since it's relatively minor, so should I restart with the mastery checks once it's feeling better again? Or should I start something new (like starting at week 1 on one of the progressions to take it extra easy)? I'm leaning towards this since it's possible that even though I could pass the masteries due to previously established core strength, I may have had a weak link with rectus femoris that I'll need to address.

Also, I was thinking of starting on the handstand series while this heals (since the injury area is unaffected by handstands). Is this a bad idea for any reason?

Thanks for any input you may have.

In case of a tweak like this, my experience is that it is always best to proceed conservatively. Reduce the volume and/or ROM for the progressions that load the affected muscles and let it recover properly.  You could maybe start at block 2 or something.  In any case you should absolutely avoid movements that cause any acute pain.

Handstand series is designed to be run in parallel with foundation, so I don't see any reason not to start with it.