Adding two strides is not something I would do with beginners, or poor hurdlers!
I do it with experienced hurdlers who can handle having more speed than usual, who need some extra challenges… So the two girls I have used this with this year both ran under 15 sec in the 100m hurdles. For the same reason (to experience and learn to handle more speed), I take hurdles away – so they run for instance hurdles 1-2-3-5-6-7 or even 1-2-3-6-7-8 (or some other variations)…
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