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July 25, 2017

What goes up must come down: working out the impact of hills on the difficulty of a race

Tim Beeson-Jones is fresh out of his fluid mechanics PhD at the University of Cambridge and has been to developing our analytical tools at LetsDoThis.com

Try racing up Ben Nevis at a speed that would impress a mountain goat and you’ll find it’s a lot harder than running the same distance on the flat. But by how much? Tim has been doing a bit of research to try and find out.

William W. Naismith was a Scottish mountaineer who walked upon mountains green and pastures pleasant towards the end of the Victorian era. A hiking legend, he completed the first winter ascent of the North-East Buttress of Ben Nevis in 1896, and at the age of 60 he walked the casual distance of 100km from Glasgow to the summit of Ben Lomand and back in just 20 hours. Naismith founded the Scottish Mountaineering Club and, fortunately for us, documented his trips.

An unlikely photograph of W. W. Naismith (1856–1935) in his least used position: sitting down.

The last sentence of one of his post-jaunt reports was the very helpful note that “men should allow 1 hour per 3 miles on the map and an additional 1 hour per 2000 feet of ascent”. It has been noted that, for most runners, this is roughly equivalent to saying “to account for any changes in elevation, add on 8 times the distance of ascent to the distance you thought you were going”. This is really handy for people who find themselves orienteering in hilly areas as they can then work out the Flat Equivalent Distance (FED) of, say, going over a hill rather than round it and then choose the shorter route. But how accurate is this rule?

We reckon with its unrelenting up’s and down’s, that 42k marathon is really more like a monster 58k ultra…

Naismith arrived at this equivalence through a lifetime of experience (and also a good old fashioned finger in the air). It is, however, a slightly simplistic model insofar as the additional time doesn’t explicitly depend on the slope of the hill, just the total ascent. It also doesn’t account for what happens when you’re going downhill. Indeed, one might expect a shallow downhill gradient to be beneficial until a critical steepness is reached, at which point one might expect further steepness to slow you down as you try and keep your balance. We’ve used the research from a leading UK sports university to gain insight into the relationship between the additional effort required and slope (including both positive and negative incline). Building on this, we’ve calculated the FEDs for a number of different popular races and found some interesting results. For example, if you were disappointed with your time on the CTS Dorset Marathon then fear not! We reckon with its unrelenting up’s and down’s, that 42k marathon is really more like a monster 58k ultra, so don’t sweat it. Or in fact do…loads.

Beware of the saw-tooth Coastal Trail Series Dorset Marathon: it may bite if provoked

This information will do a few things:

  1. It feeds into the difficulty rating we’re developing so you know what you’re signing up for when you book an event through letsdothis.com.
  2. Once you’ve decided to take the plunge, if you tell us roughly what time you might run it on the flat (or your target overall pace) then you can use the split guide we’re developing to balance out the different sections, with hilliness factored in.
  3. Finally, this info feeds into the predictor we’re developing, which will give people times to aim for given past performances and their training data. Watch this space!
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The Challenges Women Face in Running and How It Impacts Participation

Running is often lauded as one of the most accessible sports—just lace up your trainers and go. However, for many women, the barriers to participation go far beyond the logistical. While safety concerns are frequently highlighted, deeper systemic issues like access to the sport and unequal treatment are also preventing more women from running. It was a topic keenly discussed at our In Her Stride panel held at the end of November, with key members of the female running community including Sophie Power, Tasha Thompson, Rehana Mawani and Emily Shane. 

Running is often lauded as one of the most accessible sports—just lace up your trainers and go. However, for many women, the barriers to participation go far beyond the logistical. While safety concerns are frequently highlighted, deeper systemic issues like access to the sport and unequal treatment are also preventing more women from running. It was a topic keenly discussed at our In Her Stride panel held at the end of November, with key members of the female running community including Sophie Power, Tasha Thompson, Rehana Mawani and Emily Shane. 

Before we kick things off however, we should highlight that female participation in running events is growing, and this is a great thing! According to data from Let’s Do This, women in their 20s are the fastest-growing demographic in event participation this year. However despite this, women are still 16% less likely to run every week compared to men. This disparity is particularly striking given that women report higher levels of personal benefits from running, such as improved fitness, better sleep, and reduced stress.

The reasons for this are complex and personal, however we have broken down three key challenges discussed during our panel and the solutions explored that could help address them.

1. The Pressure of Pace

One of the biggest hurdles for many women is the pressure to run faster. Despite the average UK woman’s running speed of 06:37 min/km (according to Strava), most run clubs don’t cater to this with the slowest pace often around 6 minutes per km. Add to this the relentless focus on personal bests and fast times on social media, and it’s no surprise that many women feel too intimidated to join in. 

Thankfully, there are starting to be more people rebelling against this speed obsession, including our panelist, Emily Shane. Emily has been leading the charge to encourage more women to disregard pace and focus on the experience of running to drive uptake amongst women. Initiatives like events without cutoff times and more inclusive pace groups at running clubs are vital to creating a more welcoming environment and broadening the benefits of running to the experience and community. 

2. Perception of Sport in Schools

One of the topics hotly discussed was how for many girls, the barriers to enjoying physical activity start at school. Puberty, coupled with changing bodies and fluctuating emotions, can make sports feel daunting and uncomfortable for teenage girls. Research highlights this disparity: only 38% of girls enjoy sport and exercise compared to 53% of boys, and just 26% of girls feel confident in physical activity versus 43% of boys.

The panel emphasised the need to address this such as:

  • Introducing a wider variety of sports and fitness activities to cater to different interests
  • Providing more supportive and confidence-boosting PE kits.
  • Showcasing more female role models in sport to inspire young girls.

By addressing these issues at the school level, we can foster a love of sport that lasts into adulthood.

3. Treatment at Events

This is a topic that panelist Sophie Power, founder of SheRACES is incredibly knowledgeable and passionate about. Even at organised running events, women often experience unequal treatment. From “unisex: t-shirts (which are actually designed for men) to a lack of sanitary products in portaloos, these "small things" can collectively make women feel like an afterthought. Prize money inequality and rigid event policies—like no deferral options for pregnant or postpartum women—further highlight these disparities.

Thankfully, initiatives like the 50:50 campaign by Threshold (a campaign to get 50% of women at Ultra startlines vs. the current average of 30%) and the advocacy work of SheRACES are driving change, and there are many amazing event organisers such as Maverick, Threshold, Why We Run and many more, that are working hard to make their events are inclusive as possible for women. 

Despite these challenges, the panel and attendees felt overwhelmingly optimistic about the future of running for women and the benefits it brings us. Progress is being made, however we all need to add our voices to the conversation to help more women get into the sport and reap the benefits. 

Some Helpful Resources

Here are a few helpful resources. This list isn’t exhaustive by any means, however is a good starting point for those looking for inspiration on where to start. 

Female friendly events: 

Female Only Run Clubs

From Radio to Race Day: Hattie Pearson’s Path to Endurance Event Glory

Hattie Pearson is the type of person who doesn’t just dabble in fitness (or most things…!) She dives in headfirst, often with no hand-holding (except, perhaps, metaphorically). From her first triathlon in 2021 to a series of jaw-dropping endurance feats in 2024, she’s been redefining what’s possible with determination, community, and a big ‘YES’ attitude.

Hattie Pearson is the type of person who doesn’t just dabble in fitness (or most things…!) She dives in headfirst, often with no hand-holding (except, perhaps, metaphorically). From her first triathlon in 2021 to a series of jaw-dropping endurance feats in 2024, she’s been redefining what’s possible with determination, community, and a big ‘YES’ attitude.

Just say YES

Hattie’s ‘yes’ streak started when a friend and her decided to do a sprint triathlon together. “We had such a great time,” Hattie recalls, “and I was like, I want to do more of this.” That spark quickly turned into a blaze of ambition. By the following year, she was competing in Outlaw triathlons and even signing up for a full-distance Ironman—before completing her first half-distance event. “I didn’t give myself the choice to not carry on,” she says.

The Power of Community

For Hattie, discovering the 10IronWomen network—a group committed to gender parity in triathlons—was a game-changer. “It’s amazing to see a community encouraging women and non-binary folk to show up,” she explains. “Seeing others doing it made me think, I want to be a part of this.” That sense of solidarity and shared purpose has been a recurring theme, whether she’s lacing up for a winter triathlon in the Alps or a grueling ultra-marathon closer to home.

A Year of Big Goals

This year, Hattie set herself a dizzying list of challenges. She swam 500 kilometers (yep, that’s half a million meters!) and tackled a range of events, including a winter triathlon complete with ski touring, the Étape du Tour cycling challenge, and her first ultra-marathon. Each was hard in its own way—whether it was battling snowy trails with crampons or smashing out seven-and-a-half-minute miles for 13.1 miles. But for Hattie, the difficulty is the point. “Every time I achieve something I thought was impossible, I remind myself: I can do hard things.

Balance and Burnout

With goals that ambitious, fitting it all in can be a challenge. Early mornings help. “I’m one of those people who can get up at 5:00 a.m,” Hattie admits, however it also takes a lot of discipline. With her work on Hits Radio starting later in the day, she carves out time for training, dog walks, and the occasional tantrum over broken goggles. “I’ve definitely had those ‘forgetting-my-swimming-costume’ moments,” she laughs. But her key to staying motivated is simple: keep it fresh and fun. Whether it’s joining her triathlon club for training or trying a completely new event, keeping it fun and different is the secret to staying motivated and on track to reach your goals. 

Advice for Aspiring Endurance Athletes

For anyone looking to follow in her footsteps (or strokes), Hattie has this advice:

  • Be patient. Results don’t come overnight, and the journey is as important as the destination.
  • Stop comparing. “Your journey is completely your own. Social media only shows the highlights,” she reminds us.
  • Find your community. Whether it’s a running club, a neighbor for early morning jogs, or an online network, accountability and camaraderie make all the difference.

What’s Next for Hattie?

In 2025, Hattie plans to tackle her first multi-day event, the Monster Triathlon. Admittedly it is as scary as it sounds, kicking off with a 5K swim in Loch Ness, followed by a 1,000-kilometer bike ride to Windsor, and wraps up with a casual 50K run to London(!). Her goals also include more open-water swimming, trail running, and maybe—just maybe—an even bigger endurance challenge. (Though definitely not swimming the English Channel: “No way am I swimming through jellyfish without a wetsuit!”)

Hattie Pearson’s journey is more than a personal triumph. It’s a testament to the power of showing up, saying yes, and proving that with the right mindset, anything is possible. Whether you’re tackling your first 5K or dreaming of an ultra-marathon, Hattie’s story is proof that the finish line is worth the hard miles. And when you cross it? You’ve won your race—medal or not. 🏅

Make your own electrolyte drink

Why spend on expensive sports drinks when you can make a natural, hydrating electrolyte drink right at home? With just a few simple ingredients, you can create a refreshing blend packed with essential minerals and hydration-boosting properties. Perfect for fueling your workout or post-run recovery, this homemade option keeps it natural, affordable, and effective.

Why spend on expensive sports drinks when you can make a natural, hydrating electrolyte drink right at home? With just a few simple ingredients, you can create a refreshing blend packed with essential minerals and hydration-boosting properties.  Perfect for fueling your workout or post-run recovery, this homemade option keeps it natural, affordable, and effective.

Ingredients:

  • 1 pinch of high-quality sea salt
  • Small piece of fresh ginger, peeled
  • 500ml coconut water (e.g., Rebel Kitchen)
  • Juice of 1 lime
  • Fresh mint leaves

Instructions:

  1. Prepare Salt & Ginger: Add a pinch of sea salt and the peeled ginger to a blender.
  2. Add Coconut Water & Lime: Pour in the coconut water, squeeze in the lime juice, and add a few mint leaves.
  3. Blend & Serve: Blend until smooth, pour into a glass, and garnish with extra mint. Enjoy your refreshing, hydrating drink!

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