Arizona Marathon: T-22 Days

O.K., so I think I’ll do a short series of posts on my current training regimen.

What is Speed?

There are two basic elements to running speed: stride length and stride rate. 

Stride Length

Stride length is the basic measure of how long your stride is.  There are a few ways to measure that but the most direct is to just find a clean soft surface and run across it with your normal stride.  Then go back, hopefully you left shoe impressions, and measure the distance between the heel marks of one foot and the heel mark of the other foot.  That will tell you how long your stride is.  (Yes, you can measure toe to toe instead if you want)

Another way to measure it to count how many strides it takes you to cover a known distance and then divide.  Maybe you have a high school football field handy and you can start at the goal line, run at your normal pace and count how many strides it takes you you to get from the 10 yard line to the 20 yard line.  If it takes you 10 strides to cover that distance (30 feet) then you have a 3 foot long stride.

If you have 3 foot long stride then it will take you 1,760 strides to cover 1 mile and 46,112 strides to complete a marathon.  If you can add just 1 inch to your stride length you can reduce that number to 1,712 strides per mile or 44,854 strides to complete the marathon.  That’s a savings of more than 1258 strides over the course of the marathon!  If you average 125 strides per minute then just by adding that 1 inch to your stride rate you can cut more than 10 minutes off your marathon time. (assuming you maintain that same 125 stride/minute cadence).

Of course there are some dangers to increasing your stride length…first of all you might reduce your stride rate.  If you increase your stride length by 2.5% but reduce your stride rate by 2.5% then you haven’t gained anything.

The bigger danger of increasing your stride rate is that you might start to over-stride and that can cause injury.

Stride Rate

Stride rate is simply the cadence at which your footfalls land.  It’s pretty easy to measure, while you’re running at your race pace just count the number of strides you take in one minute.  Do several counts and average them – since they might not all be exactly the same.  A typical average rate might be 125, 150 or even higher.  Elite marathoners will reach upwards of 180 strides per minute.  Some recreational runners may be as low as 80.

If you can increase your stride rate, without reducing your stride length, you can increase your speed.  If you can increase your cadence from 110 strides per minute to 120 strides per minute, for example, you can cut about 30 minutes off your marathon time (again, assuming you maintain a 3′ stride length).

So…if you want to run faster you need to either increase your stride length or your stride rate or both!

Next post we’ll talk about doing that and about the third factor in Marathon training: Effort.

-B-

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