Sunday, 4 September 2011

The AST percentage, how it works

Posted by speedygeoff on Sunday, September 04, 2011 with
For our Veterans Athletic Club races, you will often see me publish a "percentage" figure next to the time for each athlete. This is the AST percentage, with which you can compare performances by allowing for the differences in age and gender, and with which you can compare your own performances across different events or from year to year as you slow down with age.

The formula is very simple:

AST = WMA / TIME * 100

where WMA is an age standard time from a World Masters Athletics table of times at or near world bests, smoothed, for each individual age, not just age group.

Suppose for example 10 minutes were 100% (ie WMA = 10), here are some of the percentages

10 mins = 100%
15 mins = 66%
20 mins = 50%
30 mins = 33%
40 mins = 25%
50 mins = 20%, etc.

Close to the “100%” mark the AST changes rapidly, but as times get slower the AST changes much more slowly, it never reaches zero unless you were to take an infinitely long time!

And if you want to know what the value for WMA is in any instance, simply invert the formula, so that it reads

WMA = AST * TIME /100

Jen Bright managing an impossible zero AST at Mt Taylor. i.e. she didn't compete there.

Results
BBQ Stakes Wednesday 31/8
Gary Bowen
28:04 27:04
Andy Matthews 28:08
Helen Larmour 28:10
Bob Harlow 28:15
Roger Pilkington 29:02
Jen Bright 29:03
Ruth Baussmann 35:40
Kerrie Tanner 36:18
Caroline Campbell 39:47

At today's High Noon meet, Kathy Southgate smashed the ACT W55 3000m record. and was only 3 seconds outside the national record. Fantastic run, about 11:17!