The Diamonds monthly P/AR competition

 The Diamonds monthly P/AR competition 

Vianney Koelman 

Dutch Eindhoven Rowing Association Beatrix 

and

The Diamonds (Over Sixties Erging Group)

 

Cyclists are used to a power-to-weight performance metric measured in Watts per kilogram. The power-to-age-reserve ratio (abbreviated as P/AR and measured in Watts per year) provides us with a somewhat similar metric. The objective of this novel metric is to create a level playing field across sexes and ages for ergometer events such as RowErg and BikeErg competitions. 

So what is 'age-reserve'? We are all aware that once we enter our thirties, the power our bodies are capable of generating will gradually drop. Every year we grow older, the odds are our power figures will be less than those from a year before. This also holds for world-class athletes. As an example, below figure shows the power delivered by male and female RowErg 2k world record holders against the athlete’s age. 

Straight lines fit nicely through both sets of data points. These straight lines effectively represent the age decline of world-record level fitness for males and females.  When extrapolated to high age, both straight lines will cross the age-axis, indicating a vanishing power figure. This happens at around an age of 120. So the age at which world-record level fitness drops to zero corresponds to the maximum age achievable by humans (also roughly 120 years), as it should be. 

The age-reserve measures the number of years an individual is away from the age above which the athlete's power is expected to vanish. In other words, the age-reserve for an individual equates to 120 minus the age of that individual. 

In above plot, as both male and female power performances follow straight lines that crosses the age-axis at the same age of 120, it follows that by a re-scaling both straight lines can be made to overlay. Effectively, if one multiplies the powers generated by females by 44, and the power generated by males by 28,  the female and male performances nicely overlay. We use these sex-corrected powers to define the P/AR ratio. So, for males this ratio is the 28 times the power generated divided by the age-reserve. For females it is 44 times the power generated divided by the age-reserve.  

In order to realise a level playing field also across weight classes, we expand the use of these power multipliers. Using multipliers of 28, 32, 44 and 49 for heavyweight males, lightweight males, heavyweight females, and lightweight females, respectively, we achieve a level playing field across sex and body weight classes.  The thus-defined P/AR metric is used to create the monthly Diamonds-internal CTC challenge that attracts hundreds of male and female participants of varying ages and covering a wide range of body weights. This is achieved simply by creating a leaderboard based on the P/AR score for each participant that is calculated from the average power realized during the challenge.