I'm on week 19 of Herrick's 1/2 IM training plan (see: http://www.beginnertriathlete.com/cms/article-detail.asp?articleid=... Toworrow, on the run session, I have to do 20 seconde strides. It may sound silly, but, what does it mean ? (sorry, I'm French Canadian :-) ). I always related the word with the movement of the legs while running but not as "accelerations" as it seems to mean in the plan... Can anyone light me there ?
Strides are a drill to help you improve your running cadence through monitoring the number of right foot strikes in twenty seconds. Basically, start counting the number of times that your right foot hits the ground in twenty seconds - aim for thirty strikes. If you are under (which you probably will be) pick up your cadence for the next set of strides. Ultimately you would like to maintain 90rpms for the duration of the run - the strides just help you to learn what that feels like.
I had meant them as accelerations...20-30second bursts which build up towards max. speed with an emphasis on clean striding and footstrike. Not too concerned with counting footstrikes here--do that during normal running. The point of these is to get your body used to very quick turnover.
If you're running on a trail/field or other place far away from roads, cars, bikes, trees, etc you can do a derivative of this drill that I call the Darwin drill. Do the same accelerations but with eyes closed-maybe build up speed for 10seconds then continue with eyes closed for another 10 seconds and visualize where your feet are striking, upper body movement, pushing off from the hips, etc. Again, only do this in an extremely open, flat area. Otherwise we will see you as a Darwin award nominee.