Leading The Pack?
How the London Marathon is redefining event sustainability
Running the London Marathon is a testament to the endurance of the human body and spirit. Participants push themselves through the 26.2 mile course, but after the finish line the event has previously left as much as seven tonnes of rubbish and four tonnes of recycling behind.
For most runners, the historic environmental impact of the London Marathon was in direct opposition with ingrained positive practices at the event, such as a culture of raising money for charity that saw a world record £73.5 million donated in 2024. As a result, the running community has emerged as an unexpected catalyst for sustainable event practices, and organisers are trying to keep up the pace.
This article asks why the running community has a unique environmental consciousness, highlights what the London Marathon has done to meet these demands, and suggests how sustainability markers should be used for the event's future progress.
Grassroots
The running community's demand for sustainability
The motivation for running a marathon goes far beyond the desire to challenge your body and mind. From supporting other's fitness goals to raising money for charity, runners' impetus is more than their own PRs.
These motivations are often found in informal initiatives, beginning with a few friends who decide to start a run club or a local movement like Park Run. While other sports require a level of structure and organisation — purchasing equipment, booking a pitch, gathering the right number of players — running's low barrier to entry naturally creates a culture of self-organisation. In that vein, sustainability at running events begins with runners themselves.
Three years ago, Tony Piedade read a Guardian article revealing that trainers take an average of 1,000 years to decompose in landfill. A passionate member of the running community, Tony had already created the platform JoggingBuddy in 2009 to help others find running partners and whole-heartedly believes in the positive impact of the sport. When he couldn't find a solution for recycling his own trainers, he was frustrated that his running community was part of the environmental problem.
In the spirit of running's self-organisation, Tony created his own recycling campaign, JogOn, and began collecting unwanted shoes in his garage five days later. He remembers, "That was it. There was no planning. There was no business plan. There was no overarching strategy. It was 'let's do something and see what happens'." Without any partnerships or publicity, JogOn quickly grabbed the attention of the running community and shoes were donated in droves.
Since 2022, JogOn has grown drastically, partnering with the London Marathon from 2024 and collaborating with name-brands like EveryoneActive and SportsShoes. The campaign has also outgrown Tony's garage to its own warehouse system and now operates a collection network through a partnership with Evri. But, JogOn is still inherently self-led, managed by a handful of volunteers. Their impressive results — 32 tonnes of trainers removed from landfill as of February this year — despite any sponsorship illustrates a mindset at the core of the running community: they don't wait for top-down change to make an impact.
“Well, the thing about runners is that it is an amazing community, right? We love being outdoors. We value being out in nature. And by a natural osmosis, there's an attributed value to protecting it.
So do runners mostly stop and think about the impact of their shoes or the impact of their gear when they discard it? Not all of them, but it is increasing. And I think as a cohort, they will actively seek out events that provide sustainability credentials as part of that experience.”
Many runner's passion for sustainability stems from personal connections with nature. In preparing for a marathon, runners log thousands of hours and miles outdoors, which fosters an inherent appreciation for the environment and provides personal motivation to care about the sport's impact.
This readily translates to grassroots initiatives, and naturally affects attitudes to running events themselves. The Trees Not Tees movement, which aims to combat unwanted event merchandise that goes unused or ends up in landfill, has a familiar origin with the running community.
The idea was born out of frustration at the ridiculous number of t-shirts produced for events that often end up unworn in the bottom of a wardrobe, or piled up in landfill.
We were founded by ultra-runner Jim Mann, who saw a way to flip that model on its head and give people something they could feel genuinely proud of — a tree sponsored in their name, in a real forest, forming part of a much larger climate solution.”
This ethos of personal responsibility sets the running community apart, and the recent passion for sustainability initiatives intersects with the existing altruistic efforts of runners. Individually, more and more runners are opting to sponsor environmental charities. A spokesperson for the environmental chairty Plantlife highlighted that 2025 London Marathon participants had already raised £10,000 for the charity, which has "not only raised important funds but also heightened awareness of our mission to protect and restore wild plants and fungi, ensuring they thrive for generations to come."
But broader synergies are also being forged between environmental and social concerns. The Salvation Army's partnership with the London Marathon collected a record-breaking 18.9 tonnes of discarded clothing from the start line last year, filling charity shops and funding the charity's social initiatives.
A commitment to sustaining our planet helps to drive lasting social and environmental change. We work with community groups, large organisations, local authorities, schools, colleges and individuals — all who share our aims to help others and help protect our planet.
The funds we raise as the trading arm of the charity support the work of The Salvation Army. In communities across the UK, Salvation Army officers, volunteers and employees are helping those struggling to make ends meet or providing opportunities to help transform lives.
Further illustrating the intersection between environmental and social justice, JogOn has begun sorting through collected shoes, donating those in good condition through local partnerships with schools and HM Prisons, alongside contributing to global humanitarian appeals.
With such a strength of grassroots sustainability initiatives, the pressure is on for organisers to keep up the pace.
The Long Run
The London Marathon's sustainability journey
Harnessing the demand for sustainability initiatives, the London Marathon began making significant strides towards sustainability in 2018. Change was low-stakes at first, such as encouraging the use of reusable water bottles, but has now grown into a central pillar of the event.
2018
Partnership with the environmental consultancy Environmental Resources Management
- Developed an Environmental Management System for collecting data and tracking performance.
2019
Initiatives begin with reducing single-use water bottles
- Used recycled plastic water bottles
- Trialled compostable cups
- 30,000 edible, seaweed-based, biodegradable capsules full of Lucozade
- Bottle belts made from 90% recycled materials are used by 700 runners
2020
Launched the sustainability report “Leaving The Right Impression”
- First comprehensive public report on waste and emissions
- No mass-participation event due to Covid-19
2021
Introduced a £26 carbon levy for international participants
- Use levy to fund offsetting projects
- Clothing donation system introduced at the start line
2022
TCS becomes Title Partner
- Mile markers made from event waste and recycled ocean plastic, created by Scaled
- Six fully-electric lead vehicles
- New Balance finisher T-shirts, made from 100% recyclable polyester
- Closed-loop system to recycle empty bottles
- First use of the ReScore App
2023
Gold Certification from the Council for Responsible Sport
- Partnership launched with Trees Not Tees offering an alternative to Finiser t-shirts
- Partnership with CUR8 for carbon removal of 280 tonnes of CO2
- 100% electric lead vehicles and over 50% electric logistics vehicles
- Finisher bags made from sugar cane
2024
Synergy between social and environmental initiatives
- Partnership launched with JogOn to encourage the reuse and recycling of running shoes
- Leftover food and drink donated to the Felix Project
- Partnership with the Salvation Army for recycling discarded clothing
- 1,935 tonnes of CO2 removal credits purchased from CUR8
- Medals made from recycled zinc
2025
First Organiser to receive the Evergreen Organisational Certification from the Council for Responsible Sport
- "Verified Champions" initiative launched for TikTok creators to document the event’s sustainable initiatives
- NPK Recovery recycles urine into fertiliser
- Smart registration technology
- Goal to remove more carbon than their event operations emit by 2025
2030
Total Net Zero Goal
The Data Challenge
The difficulty with measuring and implementing sustainability metrics
While there's clear momentum, measuring the environmental impact of the London Marathon's initiatives presents a significant challenge. As a result, the partnership with the Council for Responsible Sport, which assesses and certifies sporting events, is critical in benchmarking the event's sustainability. In a familiar origin story, the Council began with small-scale running events and has since grown into a widespread organisation that has certified some of the world's largest events.
The council was founded in 2007 by sports and sustainability professionals who crossed paths in their different careers and said, "hey, I think we're seeing this trend."
At the time, it was much smaller events in Oregon and California that needed a sustainability marker, but there was nothing there.
The London Marathon initially received the Council's Gold Certification in 2023, endorsing the event for two years. This year, London Marathon Events became the first organisation to receive the Evergreen Certification — an endorsement of the entire organisation — demonstrating continuous improvement of all their events against environmental targets.
Measuring event sustainability is a complex task, and the Council's assessment was created in collaboration with both environmental experts and sporting events organisers to create a comprehensive framework. The approach was "academic", with peer reviews and an open discussion of the Council's initial plans before the certifications were launched. In the 18 years since, the Council's standards have adapted to stay abreast of sustianbility trends.
In 2007, saying we recycle or we don't use single use plastic at our events was a big deal. Doing that now, it's still wonderful, but there's probably more we could do.
So we go through and update [the standards] over time, just to make sure it's really aligned, and people that are undertaking the certification push the barrier a little bit more — it's that little step above what a regular event might be doing.
The assessment process itself is rigorous, involving continuous reporting and an on-site assessment from a member of the Council. Events organisers must give evidence and are scored across five categories:
- Planning & Communications
- Procurement
- Resource Management
- Access & Equity
- Community Legacy
Kat Phelan describes the process for the Gold Certification by the Council for Responsible Sport
While it's a large task, much of the assessment is made possible by Tata Consultancy Services' (TCS) ReScore app. The technology enables sporting event organisers to measure, report, verify, and certify against the Council's sustainability standards in real-time. Used by more than 50 sporting events, the app gives organisers the much-needed data for sustainable decision making and evidence for their impact.
“At TCS, we see sport as a powerful platform to advance sustainability. Through innovations like the ReScore app, we’re helping race organizers and participants measure and reduce their environmental impact.
By combining our technology with our values, we’re making every stride count toward a more sustainable future."
Just as particpants get access to data on their marathon progress and timesplits through the TCS London Marathon app, providing individuals with data on their environmental contributions also proves powerful. Trees Not Tees have recently begun providing all particpants with their own profile on the platform Sumthing, where they can track every tree that they've sponsored. Their lead, Abbie McGrath, described it as "a more transparent, connected way to commemorate an achievement and be part of a bigger picture."
Each of the 7532 trees planted through Trees Not Tees collaboration with the London Marathon can be seen below by searching 'London Marathon'.
Though comprehensive event data is guiding the marathon's approach and there's clearly participant appetite for greater visibility, the public can't quite get the full picture of the London Marathon's sustainability markers. In the event's annual Leaving The Right Impression Report, the data changes year-on-year, reducing visibility of the long-term improvements. Similarly, the event's carbon removal practices can be a misleading contributor to headline net-zero statistics, with 'credits' purchased in carbon offsetting projects to justify emissions rather than avoid them.
Further, the net-zero problem is unavoidable for the event without significant changes to its operations. A core challenge for marathons remains international travel, with 95% of total emissions from the 2022 London Marathon coming from its 9,920 international participants. No use of electric vehicles or public transport schemes can counterbalance this effect without drawing upon flawed external aids like carbon credits.
This creates a central problem for the event's sustainability — how to balance accurately measuring it's environmental impact with maintaining the iconic practices of the event.
The sustainability story is double-sided... I think I would always caution this sort of balance between doing an event or not doing an event because of the sustainability criteria.
Radical action, like preventing international travel to the event, would undermine the community benefits, and restrictive sustainability practices could create friction that prevents action from both participants and events organisers. While there's no denying the ambitious speed and scale of the London Marathon's sustainability initiatives, it may be best to stick to a joggers pace and incrementally progress to the 2030 net-zero goal.
I always say we can shut up shop and close our doors when sustainable sport and doing certification like this doesn't feel like an extra added piece on to what you're doing. It is just a process that you follow and it's so ingrained in your culture that it doesn't feel like an add-on
In the move towards sustainable events, it's clear that marathons are leading the pack. Kat added "I do think sports have always served as a guide for a lot of people. It's such a gathering place, and so it's very well poised to create this kind of cultural shift in how we view mass participation events." But, other event types are following suit, with the Council for Responsible Sports recently certifying the New Orleans Jazz & Heritage Festival and the Isle of Wight Festival declaring its mission to become 'the most sustainable festival in the country'.
There's much to be learned from the London Marathon's ability to overcome the inherent obstacles in organising sustainable large-scale events, from the trust-building exercise of independent assessment to ingenious environmental practices like transforming urine into fertiliser. But, the core of the London Marathon's success has been engagement with grassroots initiatives and it's important for the community to set the markers in its future progress.
