My Eddington Number

Whilst trying to sort out why it was so difficult to get the GPS traces from my Garmin Edge to display when loaded into various Mapping websites I came across an interesting Blog: Tlatelet - "Ridding the World of Grumpy Old Men" - basically the Blog of another silver cyclist! I think there must have been an interesting snippet on GPS. somewhere in it. However what caught my eye was a reference (and Post) to the Eddington Number for cyclists. Sir Arthur Stanley Eddington (link 2) was an Astrophysicist who amongst other things developed the Eddington Limit which relates to the natural limit of the luminosity of stars. Apparently he was a gifted communicator as well as scientist and during the 20s and 30s give many lectures as well as Radio Broadcasts where he added a philosophical twist to the physics of the time - Relativity and Quantum Physics.

He graduated from Cambridge and later came back to Cambridge as the director of the Cambridge Observatory. I like to think that his time in Cambridge (a cycling City) as an Undergraduate led to his interest in cycling. The Wikipedia article has a small footnote on the Eddington Number (cycling), E. E is defined as the number of days a cyclist has cycled more then E miles. So if in a lifetime of cycling you had an E number of 56 it would mean that on 56 occasions you had cycled 56 miles (in a day). The implied message being that a high E number is good. The way I look at it is that the degree of difficulty follows a square law - since to achieve an E number of 10 requires 10 x 10mile rides, a total of 100 miles. Whilst an E number of 20 requires 20 x 20miles, a total of 400miles. So although the E number doubles the total number of miles increases by 4 (2x2). The further twist it is mileage per day that is counted then it requires consistency in cycling long distances rather than just clocking up miles. So the intensity increases - 10 miles in 10 days is much easier than 100 miles on one day!

I first started logging my cycle trips back in '94 (19th Aug '94 to be exact). I am not totally sure why. I had resumed cycling to combat a sedentary life a couple of years earlier. I had a sales role which involved a lot of international travel and had a young son and so felt the need to improve my fitness. As I discovered with sales it is important to track and measure progress on accounts (rather than just the eventual sale) and so for the same reason I started to log my cycling - most of the time it was a 30 minute cycle of about 12Km - all I could fit in. All of this was kept on a spreadsheet - and when a few years later ('97) I got a Psion Series 5 it became the repository for my cycling records. I have always enjoyed cycling, I was born in the days when it was common for school-kids to cycle to school, come rain or shine (which I did). The bicycle was my passport to roam. In my first job the bicycle was the mode of transport for socialising (Er well going to the pub with my mates really).

This is a long way of saying that I have all my data on a spreadsheet - well over several pages actually. I keep a separate page for each year and then a summary page comparing past years. The record is continuous (all my cycling) - but I did not cycling during 2000 and 2001. I had a Millennium moment and tore the cartilage in my left knee. (It was probably in August '99 which is when records stop). After enduring the problem for some time it got worse and after seeing a Specialist , who thought I was too young for the op' I re-started cycling as a way of stabilising the knee. (With the Doctor's agreement of course.) So I have around 112,000Km (70,000 miles) of cycling recorded and it was pretty straightforward to create a page to calculate my E number. This is one of the charts I keep, it summarises the yearly number of kilometres I have cycled. This year (2010) at the end of Month 5 (May) I have cycled a little over 5,000Km so am on track to hit my target of 12,000Km. I managed to achieve over 12,500Km last year despite being off the bike for 6 weeks after being SMIDSY'd by an inattentive car driver.

My E number calculator is not sophisticated you have to enter a number of miles and then it reports on the number of days when my cycling has exceed that number. So you have to increase the number of miles and see how many days get reported. My E number - well I have cycled in excess of 75 miles on a total of 77 days. I have cycled 76 miles on 75 different days so one more ride of 76 miles will increase my E number by 1! In 2005, when I cycled from Land's End to John O' Groats, I exceeded 75 miles on 22 days.