It’s the Dereham 10 Mile race tomorrow. Will I get a personal record? What do the race prediction algorithms say?
It’s only been a week, but it’s race day again tomorrow! This time it is the turn of my nearest running club, Dereham Runners AC, with their first major event of the season, the Dereham 10 Mile. It is also race number 7 of the 2023 Sportlink Grand Prix.
Unlike all my other races to date this year, I have run this race before. In fact I ran it last year in a time of 72m15s, which was a recent best for me. And given that I ran the Reedham 10 Mile back in January of this year in 69m54s, I believe that my personal course record of 70m06s is at serious risk of being broken.
As depicted in the map above, the course is a lollipop route, starting / finishing in Dereham, run solely along country lanes to take in some of the villages and hamlets to the north east of the town. The first kilometre is a very gentle incline, which then turns into 8.5 km of gradual descent. At this point, whilst not directly running back on yourself, the gradients reverse but are more severe. Meaning, the hill that you just ran down over 8.5 kms, you have 5.5 km to get back up. You are then rewarded with a final km of a very gentle descent to the finish.
Training
In view of recovery needed following last week’s race, this week of training has been expectedly very light. Consisting purely of short easy Economy runs, totalling a similar volume to the previous week, as illustrated in the chart below.
Predictions
Below is a table of predictions from various algorithms / sources. An important point is that the Running Watch and Data Analysis Platform do not provide 10 mile race predictions, and so I have estimated values based on their 10 km and half marathon predictions.
| Algorithm | Pace (min/km) | Time (mm:ss) |
| Riegel (3.2 km Assessment) | 4:47 | 1:17:01 |
| Riegel (6 min Assessment) | 4:46 | 1:16:54 |
| Running Watch | * 4:22 * | * 1:10:20 * |
| Data Analysis Platform | * 4:15 * | * 1:08:28 * |
| TrainAsONE | 4:11 | 1:07:21 |
| Riegel (10 km Race) | 4:10 | 1:07:00 |
As can be seen in the table, Riegel, based on my latest 10 km race, is predicting a time dead on 67 minutes, with TrainAsONE only 21 seconds behind. There is then a gap of over a minute before the other algorithms have me finishing. With the slowest, Riegel (3.2 km Assessment), predicting a time around 10 minutes slower than the two fastest – Riegel (10 km Race) and TrainAsONE.
So it looks like I’ve got to target a time of 67 minutes (or just outside).
Looking at last year, I took 40 minutes to get to the bottom of the hill and consequently 32m15s to return to the finish. This represents a 10 % drop in pace from 4:19 min/km down to 4:48 min/km. Looking at the same statistics for my course record, the drop in performance was 6 %.
I’m much fitter than last year, and believe the 6% difference between up and downhill pace is more likely this year.
Consequently, in order to hit a total time of 67 minutes I would need to get to the bottom of the hill in a time of around 38m45s (a pace of 4:04 min/km). This would leave around 28m15s (a pace of 4:20 min/km) to ascend the hill and return to the finish line.
Additionally, I have uploaded the route into the pacing guide for Running Watch. It suggests that for a 67 minute time, I would need to be at the bottom of the hill at 39m32s (4:09 min/km pace), leaving around 27m30s (4:13 min/pace) to complete the race.
I plan to run at a 4:10 min/km subjective effort. It is nice to have these numbers at the back of my mind when I hit that return point, and start the ascent. It will be interesting to see whether either of these two scenarios play out tomorrow – or something else…
Wish me luck!
(I’ll let you know how it goes.)
