This. Or Lap Normalized Power. Hit lap every once in a while and you get a fresh set of numbers to average against. This is because you can be doing 400 watts and that will barely move the needle on your total average of 250 if you've been riding for an hour or more. But if your lap is only 20 minutes long, that 400 watts will make that 20 minute average move big time and send up red flags.

So let's say your target is 250 watts for a race. This 20 or 30 minute lap you hit 249. Next one aim for 251. Next one is 253? Aim for 247 the next. Like the other guy said, it let's you go a bit high for hilly sections and a bit low for easy sections (net downhill or tailwind). Works great.

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