Standard candles and what they mean for racing

Astrophysics and triathlon?! How do the two even relate to one another? Here we discuss how a tip to understand how far away starts are can help us ascertain how our race result actually was and can help us give a truer understanding of what went well and what we would need to work on for the next race.


Everyone has a race which they do and they may or may not be disappointed by their result. This will be purely based on their times or their outcome against their age group overall results or otherwise.

As a coach, this is a really common conversation: someone will be happy because of their position or they will be really disappointed by a time they achieved (or vice-versa) and as a coach we need to be able to look at this in a very objective manner.

The open water swim is a really excellent example of this. No matter how hard people try it is impossible for the course to be identical each time. Tide times, currents, wind, evaporation in lakes, etc will make the swim course different each year even if the buoys are in exactly the same place (Not to mention the drafting effect or how straight people swim!).

How you felt the race go can be very easily misconstrued. You make get a stitch in the final km of the run and have to walk in and not realise that you nailed a new PB off the bike, or perhaps you improved your overall swim position but got disappointed because your time was slower or maybe you felt happy because you biked a faster time but weren’t as aware of that wonderful tail wind you had on a long section or your subsequent poor run. All these scenarios and many others can result in a false positive or false negative on what should be an objective reflection on how the race went

Cue “Standard Candles”

Standard candles are a name given to stars in the universe which are a known luminosity and subsequently a known distance from earth. By using both these facts, some smart trigonometry and understanding of how light intensity reduces with distance, we are able to know how far away other stars are from earth by working out the comparison to these known “Standard Candles”. Clearly, with stars being all sorts of different distances, and brightness, you couldn’t simply stay the dimmer the star the further away it is nor the opposite.

In the same way just because you were quicker on a course, it doesn’t mean you are actually quicker and just because you were beaten, it doesn’t mean you were slower!

How does astrophysics relate to triathlon results?

Simply, there will always be standard candles within a race that you can compare to. When racing there are only really two outcomes you can look at: One measure is your time, another your position. “Feel” is subjective, but shouldn’t be taken into account at this point. However, when you start looking at both of these items you may start seeing information or patterns and these patterns become more apparent when you compare it to people whom you know their relative ability compared to your own.

For example: perhaps your position overall has jumped up even though your age group position hasn’t changed and you were slower? Or maybe you were faster than someone you usually lose to. Or perhaps the winner was also slower this year (we often use the top 10% position’s time as a way of comparing overall difficulty of the course - the first athlete is likely to have had a standout day, so look at someone closer to the average than that (or maybe the top 10%, and 50%!). Perhaps the 20th placed athlete finished a lot quicker than last year indicating that perhaps times were quicker and you can adjust your objective conclusions as such; or maybe your club were racing and you went significantly faster than people you are normally training buddies with. When you begin to think about it, there are loads of very easy and very objective ways of understanding how people’s performances adjusted.

No matter what or whom you use, it is important to use a few reference points to subsequently decide on how your race went or you can assess how things are going in race too and not be disappointed by a seemingly slow swim! It is absolutely critical not to work on just one of these variables. Therefore, if you only look at time, only look at position, or only look at how you did compared to your friends, you will miss the complete picture. Use all the information you have available and see what you can learn from your result.

Now, time to go and practice some trigonometry...!