bummer, sounds 'made for PT'. You doing those 'good mornings' or 'russian glute/hamstring curls'? I never saw that sign - maplewood track on manchester?
hey I got a brilliant idea, if only hurt at interval pace, do cruise intervals at 5k or slower instead!
it was getting progressively more stiff, even when I jogged part of that last rep, so think it just needs some rest; I'm almost convinced it was from the over-stretching because that was the only thing unusual, not the usual yoga type downward dog stuff, different instructor did more hurdler type stretching