We’ve all had that feeling. You’re exhausted, at the top of a massive hill, and you’ve been walking for half the amount of time the route said it would take. You look at your map, and you’re not even close halfway.
At least, I’ve had that feeling many times when I’ve been out walking.
It’s worse when you’re the one that’s spearheaded the expedition – promising reluctant pals that they’ll be rewarded with a country pub lunch, only for them to feel irritated with your apparent inability to figure out walk timings.
So how do you calculate walk timings? Most routes will come with a rough estimate, and there are also nifty calculators you can use, like this one.
It’s also good to get into the habit of calculating it yourself. A common way is to use Naismith’s rule – William Naismith was a Scottish mountaineer from the 1800’s, way back before the first Garmin watch was invented.
Using this rule, you should allow one hour for every 3.1 miles (5km), and then add on an hour for every 600m (2,000ft) you ascend. You can also break down the ascent to an additional 10 minutes per 100m (30.5 ft).
So say you’re doing the Chess Valley walk – it’s about 10 miles in length, with an ascent of 205m in total. Using Naismith’s rule, you’d want to give yourself 3 hours and 40 minutes to complete the walk.
But not everyone’s pace is the same, right?
You can adjust any timings you calculated using Naismith’s rule with the table below, called Tranter’s Corrections. If you do this, make sure to calculate the timings based on the slowest person in the group.
|Time taken according to Naismith’s rule (hours)|
|15 (very fit)||1||1.5||2||2.75||3.5||4.5||5.5||6.75||7.75||10||12.5||14.5||17||19.5||22||24|
|40||2.75||4.25||5.75||7.5||9.5||11.5||Don’t even try it!|
Fitness in minutes is calculated as the time it takes to climb 305m over 0.5 miles.
So, I might adjust our previous walking time depending on who I’m going with – a pal who’s rather unfit might take 4 hours and 15 minutes to do the Chess Valley walk.
These are all just starting points for calculating walk timings. When you’re on the ground, you’ll inevitably experience delays – you’ll lose the footpath, take an intentional detour and of course stop for breaks. You can always reassess when those delays do happen.
It’s also a handy weapon to have in your back pocked for keeping up group morale: yes, you may have only covered a third of the route in half the time you thought the whole walk would take, but if the next section is on flatter ground then your original calculation was probably about right.