I understand the difference between stiff/medium/etc but is there an actual unit of measurement to determine it ? I think fishing poles have a "flex rating" measured in pounds, could rackets be measured the same way ?
There isn't any standard measurement - the closest is probably SOTX's test, which involves placing a weight (20kg IIRC) on the T-Joint, and measuring how much the shaft bends. I think there's another company that secures both ends of the rackets, and then places the weight halfway along the shaft, again measuring how much it bends. Honestly though, these tests aren't very meaningful at all, as a racket can feel dramatically different from what those figures might suggest. Head-heavy rackets and rackets with longer shafts always feel more flexible than they actually are, and some rackets flex higher up the shaft (have a higher "kick point") than others, due to tapered shafts etc.
