The best average power or an athlete can produce for a given amount of is their Peak Power. The term was called Critical Power for many years, and you might still find it called that, but now as coaches we are calling it Peak Power, or P, but you might see Critical Power expressed as CP.
This is expressed with a number after it, that represents the time period it is referring to, in minutes. If we are to discuss an athlete’s best power output for 1 minute, we would express this as their P1.
An important power metric for a half-ironman athlete would be P120, or their best 2 hour power output, as that is a race specific value. An Ironman athlete would want to look more at P180, or even P240, (although you won’t find that value common). A more common peak power value that is tracked is 30 minutes, since athletes tend to have a lot of 30 minute samples to track.
This metric is also used with pace in running, known as Peak Pace. It is expressed the same way, just average pace is used instead of average watts. I would recommend athletes and coaches track this value in a small unit, such as kph, (kilometers per hour), or even m/s, (meters per second), rather than mph. This smaller unit allows us to see small changes better, as going 1 mile per hour faster is tough to do.
Start tracking these values and you'll begin to understand when you're fit and where your weaknesses are. You can especially gain valuable insight when you place these into your PMC chart in WKO+, and track the trend of improvement, (or lack there of), such as here, where an athlete prepping for a 70.3 is seeing many of the pace values specific to that performance show he is ready to perform well...
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