“To measure is to know” and “If you can’t measure it, you can not improve it”
Wise words, indeed, from Lord Kelvin, the early 19th century mathematical physicist .
As someone who changed his life by tracking data (read my debut BJSM Blog ) this is the sort of confirmation bias that I cling to when I read articles, like this one , which cites research that implies that the more we track an activity, the less we will enjoy it.
With Lord Kelvin’s quotes fuelling my stance, I was ready to quickly dismiss the idea that tracking physical activity could be anything but a great idea.
And then, I remembered one of Lord Kelvin’s less celebrated quotes :
“ X– rays will prove to be a hoax”.
Whoa, if he could be so wrong about x – rays (they also changed my life ), what else did he get wrong ?
So, I read the story further and I considered if my tracking of steps, pace, distance, calories and even heart rate had become an addiction and even a chore?




re heavily discounted to the extent that it is often not much more expensive to buy four of five bars than one. Again, we could criticise people and parents, but does that actually achieve anything? Instead, let’s encourage better promotion of healthier options and motivate and inspire people to make healthier purchases.
