O.O'Brien

More GPS tracklogs overlaid on high-resolution aerial photographs in Ascent:

1. The Bushy Park Time Trial (5K) route – now going clockwise around the park.

2. A quick (700m) warm-down jog up and down one of the tree-lined terraces in Bushy Park. Notice you can see every tree.

3. Today’s exhausting orienteering race at Woolbeding Common – M21L. Quoted distance was 11.9km, but, per my GPS, I actually ran at least 14.5km.

4. A mistake on the Woolbeding Common race – at number 18 – approaching from the left. It was just after the 12km mark and I was tiring badly, so my concentration went. I swung away from the control too early, and strayed too close to the distinct vegetation change. I only found the control “by luck”, while starting to relocate back onto a path.

5. Finally, from Google Earth, a view of my steep descent from near the summit of Arthur’s Seat in Holyrood Park, Edinburgh, during my orienteering race there last summer.

I’ve been doing a few street orienteering races around London recently. These are generally in the evening, when it’s dark, but I don’t need to geek out with a head torch as street lighting is normally sufficient to be able to read the map. The races are score races – you choose your own route and aim to get as many controls in 1 hour, with stiff penalties for being late back.

Here’s my route from tonight’s LOK event in London’s West End, as viewed in Ascent’s very cool map. The start was actually at the same place as the finish (chequered flag) but my GPS only gained reception after a few minutes of running. My route included an “interesting” stretch along Oxford Street, weaving in and out of the Christmas shoppers, then down Carnaby Street, across Regent Street, and into Theatreland, Soho, Chinatown and Covent Garden, before heading back to the University of London, where the finish was.

Another interesting thing – my HR during the race has a distinctive pattern – dipping noticeably every time I stopped at a control. A “control” on a street race like this one, consists of writing down a word you would only know if you were at the correct place, into a box on the back of the map. Examples included the name of the pub in front of you, how many pillars in the church entrance, and Statue of William who? (The Lamb & Flag, 6 and Pitt, in case you were wondering.) Unlike a normal race, where with good “flow” and forward planning you can almost keep running while punching, you generally have to stop for a good 10 seconds to write down the answer. Hence, the noticeable dip, 21 times, corresponding neatly to the 21 controls I visited, and the final dip at the finish. My highest HR, 190bpm, was during a long, straight run, around halfway through, between the two clusters of controls that I visited.

Here’s an extract, again from Ascent, for a SLOW street race in suburban Wimbledon, that I ran a few weeks ago. Only part of my race is shown. Here, the colours on the route correspond to the speed I was travelling at. Dark blue is slowest and green is fastest. The blue generally occurs at the points where I’m at a control – I typically make a sharp turn here too, due to my possibly non-optimal route to the next control. I had difficulty finding the plaque on a church in the top-middle of the picture, hence why I was walking (dark blue) around it. Caxton road was on a hill, hence why I’m going fast (green) one way down it. At this resolution, you can see where I crossed each road, and whether I went straight across, or at a diagonal, or even just ran down the middle of the road to avoid slow pedestrians.

Ascent is a very impressive program, and is working great so far with my Garmin 305 wrist-mounted GPS and HR monitor.

ps. Altitude estimation is hopeless with GPS – apparently I climbed 1170m in tonight’s one hour race. In fact, the race was completely flat, I probably actually climbed no more than 30m in the entire race. Momentary echos off the high buildings in central London will probably have caused this apparently impressive climbing feat.