Starting on Friday 21 August, endurance adventurer and mental health activist Alex Staniforth will be taking on the national three peaks challenge, aiming to run the route in under nine days. The current record for the journey of over 440 miles linking the UK's three highest mountains - Ben Nevis, Scafell Pike and Snowdon (Yr Wyddfa) - was set by Tom Mountney in 2019, who completed it in an impressive 9 days 11 hours 46 minutes.

"Tom has been very supportive with my own attempt" says Alex, who in 2017 made a record breaking 5000-mile self-propelled round of the UK's 100 county high points:

"Since Climb The UK I'd been looking for another UK-based endurance challenge, and since moving to Kendal I've been mostly running in the hills. Running has been my main passion for the last few years so it made sense to focus on my (sort of) strengths.

"The National 3 Peaks was my first challenge back in 2011 aged 16 (my stepdad drove between) which ultimately inspired my Everest journey. That knackered me. In 2014 I climbed and cycled between the peaks in 4 days. That also knackered me. Completing the same journey on foot will be a totally new experience - we have to keep pushing the bar and challenging ourselves."

The schedule demands an average of 48 miles on foot per day, with over 44,000ft in total height gain. By pushing himself Alex wants to challenge the stigma of eating disorders in men, he says, and raise awareness to prevent others from developing them.

An Ordnance Survey Get Outside champion 2020, Alex has himself suffered with depression, anxiety and the eating disorder bulimia for many years. He believes that attitudes such as 'earning calories through exercise' have re-enforced an unhealthy relationship with food and exercise.

Being male, he says, made it especially difficult for Alex to talk about and it took three years before he sought help.

The stress, anxiety and isolation during lockdown has caused significant strain on mental health across the UK, with the Royal College of Psychiatrists warning there could be a 'tsunami of mental ill health' once lockdown restrictions are eased.

This year Alex co-founded a new charity, Mind Over Mountains, to help restore wellbeing through outdoor experiences. The charity provides walking events in UK National Parks, helping people build resilience and get back in touch with nature.

Alex is aiming to raise £10,000 to support people who have suffered serious setbacks from the lockdown: "We've been facing our own 'mental health mountains' recently and lockdown has helped us appreciate how important spending time outside is for our mental and physical well-being.

"At Mind Over Mountains we are determined to support those most affected and help them reconnect through the power of nature. We have just announced four new events through August to October to help people get the space and support they need."

And he suggests that the isolation resulting from the recent COVID19 lockdown may have been especially difficult to manage for people with eating disorders.

"We've all had our goals and plans thrown up in the air by COVID-19, and obviously my run was insignificant considering people were losing loved ones to Coronavirus" he tells us.

"This [3 Peaks run] was originally planned to take place in May. However the delay gave the chance to get more training and preparation in during lockdown. This time it's been very different though - it was hard to commit to a date with the lockdown restrictions and worrying about backlash, until all the elite runners came out of the woodwork smashing records! Then I managed to sprain my ankle a few weeks ago which pushed things back again. Trying to stay motivated when the finish line kept being pushed further away has been an emotional roller-coaster. But it's good practice for the real thing."

Originally he'd planned to go self-supported, in similar style to runners such as Mark Chase or Jamie Ramsay (who completed the challenge a few years ago), but with his recent ankle injury felt it was "biting off too much on a challenge that is already the hardest I've probably tried to attempt."

"A good friend Rich will be joining me for the first few days in Scotland to carry spare kit, water and food where it's quite remote and to save some weight off the pack on the hills" says Alex.

"Another friend Paul will be doing the same in the Lakes a few days later. Otherwise I've arranged my hostels and B&Bs and have prepared to be self-sufficient where needed.

"I've done most of my challenges solo, and always preferred having the space where it's a personal battle against the elements with my own routine, and where only I can let myself down. But it's also a huge boost to have support through the moments of weakness and to break up the long duration alone - I certainly wouldn't have got through many of my challenges without it."

Though the three hill stages anchor the route, more than two-thirds of the total distance will be on roads. "I've done a lot of road running in the past, so hopefully the shins remember too" he says.

"In terms of route planning I looked at the previous attempts and highlighted some variations, for example I want to run through my home village and hometown of Chester, which isn't the most direct route. Plotting it with Strava was fairly easy as it selects the most popular route to avoid any nasty surprises. I then fine-tuned it for more pleasant routes, going through towns for re-supply, and choosing trails or canal-paths where possible. Much more straightforward than plotting a route for the 100 county high points!"

48 miles, or nearly two marathons a day, would be a big achievement over two or three days (OK, just one day would do it for most of us), but nine days back to back is likely to take a huge toll. While marathons have been Alex's strongest distance to date, he's fairly new to ultra-running and admits to a lot of uncertainty as to how the cumulative miles will feel.

"Maybe that's part of the adventure" he says. "To aid recovery I'll be taking Mountain Fuel Recovery sachets and ensuring a very large meal in the evenings along with the usual stretching and foam rolling. Compression sleeves have always helped me, I take turmeric capsules and will have frozen peas on standby."

Mental resilience on the hoof is, he says, a matter of breaking the big picture down into manageable stages.

"If you think about the remaining days it can feel quite insurmountable. I tend to play number games with myself and create little incentives, for example, focusing on the next food stop in 30 minutes, or waiting until the next mile before playing a new track through the headphones. This strategy maintains momentum, offers a distraction and chomps away at the mileage. Most of all you have to remember why you're doing it and all the sacrifices you've made so far - checking your fundraising page and the encouragement on social media gives a huge boost."

"I've been very humbled that a number of businesses have donated to my charity target, pushing it towards £4,000."

• You can track his progress here
• Donations can be made here

Alex Staniforth is sponsored by: Rab, Hostelling Scotland, Ellis Brigham, Inov-8 and OMM