I've been looking into the impact of heat, humidity, and solar radiation on running times, but most data is on actual race results. See this example of research. For calculations see this example.
Are the calculations biased by data from actual races since effort levels are generally higher during a race? How much so? Some research on the central governor theory, or other effort related exercise research which I can't remember the source for, actually got professional athletes to perform equally under a higher heat index.
What I want this theory for is to track training, predict performance, and compare fitness level under different weather conditions.I find the actual calculations to be a little conservative and would like to improve them with a simple rule of thumb.