It wouldn?t be a 100 without some sort of discussion on start times and checkpoint opening times, so I thought I?d start one off! Given the start times of 10:00 and 14:00 for the Cinque Ports 100, and the checkpoint opening times on the website, I can foresee that there will be problems with queues at the early checkpoints with many people arriving early ? this is likely to cause problems of congestion for both the walkers and the checkpoint volunteers. It may be that the website opening times are only provisional and will change, in which case these problems may not arise. In any case, I think the analysis I have done to arrive at this conclusion is interesting (at least to data buffs like me!) ? and it may prompt a re-think of the timings. I will go into some detail about how I have come to this conclusion ? so well done if you read through all of this post.
I have completed 25 LDWA 100s (+ 1 unofficial 100) ? the first four of these had times of 44 hours or more and thus meant walking through both nights. For the following 22 hundreds I have finished in time to get to bed on Sunday night, and I now have a fairly consistent finishing time of between 33 and 36 hours. This means that if I start at 10:00 I can be pretty confident of finishing before it gets dark on Sunday (~10pm), but that if I were to start at 14:00 then I would be almost guaranteed to have to walk into the second night. When I talk to other walkers near the start of a 100 (after we have sorted ourselves out in the first few miles), the overwhelming aspiration on finish times is to finish in the light on Sunday ? this gives a great psychological gain, and I think that this should be taken into account when planning opening times.
On this basis, it would be reasonable that a walker/runner should be OK with starting at 14:00 if they are still confident of finishing in the light on Sunday ? this gives 32 hours, and allowing a lee-way of 2 hours for being slower than expected, this would mean that anyone expecting to finish in 30 hours or less should be happy to delay their start to 14:00, and those expecting to take >30 hours should start at 10:00.
The Cinque Ports checkpoint opening times appear to be based on a 28 hour finish time at a constant speed of ~3.61mph starting at 10:00 (sets time for CPs 1-8) and a 20 hour time at a speed of ~5.05mph starting at 14:00 (sets times for CPs 9-finish). At first glance this may seem fine as a cut-off of 28 hours is quite reasonable and more generous than the 30 hours I?ve suggested above. But of course we all know that it doesn?t really work like that, as (unlike elite athletes) we will slow down as we get further through the walk. The reasons why we slow down are many, but include:
? We spend longer at checkpoints later in the event ? we arrive at CP1 with no time spent stopped and are likely to have only brief breaks to start with, and longer breaks later in the event (particularly the breakfast CP). As an example, looking at my own timings over the past 20 hundreds, I spend an average of 2 hours stopped at CPs in the first 50 miles, and 4.5 hours in the second 50 miles.
? We slow down for many physical reasons such as blisters, aches, tiredness, sickness, low energy, you name it ?.
? We slow down when it gets dark
? We slow down for mental reasons when it gets harder to make decisions and be confident of route finding
So it is reasonable to ask the questions as to what times a walker might be expected to get to each CP for a given finish time. Fortunately we now have a lot of data to answer this question as the recent results have the CP arrival times for each walker. I have looked at the times for all the finishers of the last 2 hundreds (Dorset at NYM) and have determined the following, based on some 687 hundred completions:
? The average speed in the first section from the start to CP1 is ~143% of the overall average speed ? so someone who completes a hundred in 30 hours, with an overall average speed of 3.4mph, can be expected to reach CP1 at a speed of 4.9mph. Or looking at this the other way round, someone who arrives at CP1 at a speed of 3.6mph can expect an overall average speed of 2.5mph and a finish time of almost 40 hours (involving 4 hours of second night darkness).
? Some 90% of walkers reach CP1 at a speed faster than 128% of their eventual overall average speed ? so we all display a similar pattern of slowing.
? Well over half the hundred finishers take less than 40 hours so, with the present opening times, more than half of the walkers will have to start at 14:00 to avoid arriving early at CP1! The alternative (and more likely scenario) is that there will be a queue of at least 150 people waiting for the checkpoint to open.
? By the time a walker reaches 25 miles, the average speed will be down to 130% of the overall average, at 50 miles it is 115%, and at 75 miles 105%. The figures that we can be confident that 90% of walkers will exceed are 121%, 110% and 102% at these distances.
Given this ?normal? profile for slowing, it is possible to calculate what opening times are consistent with a particular overall average speed and starting time. Using the 28 hours (10:00) and 20 hours (14:00) targets, this gives opening times (present and suggested revision) as follows (apologies can't get the table to format nicely):
CP____Miles___Present______Revised_
Start__0_______Sat:10:00____Sat:10:00
1_____6.5_____Sat:11:40____Sat:11:10
2_____12.1____Sat:13:20____Sat:12:20
3_____18.4____Sat:15:00____Sat:13:40
4_____24.3____Sat:16:40____Sat:15:00
5_____31.5____Sat:18:40____Sat:16:50
6_____41.1____Sat:21:20____Sat:19:20
7_____44.4____Sat:22:10____Sat:20:20
8_____48.9____Sat:23:30____Sat:21:40
9_____57.8____Sun:01:20____Sun:00:10
10____66.6____Sun:03:10____Sun:02:10
11____72.5____Sun:04:20____Sun:03:30
12____77.7____Sun:05:10____Sun:04:40
13____83.2____Sun:06:20____Sun:05:50
14____89.3____Sun:07:40____Sun:07:10
15____93.9____Sun:08:30____Sun:08:20
16____97.5____Sun:09:10____Sun:09:10
End__101_____Sun:10:00____Sun:10:00
So ? in summary ? can I request that the CP opening times are reconsidered (if indeed the present suggestions are not just provisional) in order to avoid much over-crowding and congestion at the early checkpoints?
Thanks for reading this far.