Running 100 miles in under 24 hours.

Mag Balfe, winner of the annual ‘Safety Solution’s Belfast 24hr’ 100-mile event, reflects on the ups and downs of running, her training and the determination needed to run 100 miles under 24 hours. 


For Mag, the build-up to last October’s ‘Safety Solution’s Belfast 24hr’ 100-mile event began almost four years ago, in 2018, when she ran the Belfast 24-hour event for the first time and racked up 85 miles. She ran it again in 2019 and achieved 94 miles before the cut off. Hungry for the achievement of completing the 100-mile distance in a single run, she signed up to the 2021 100-mile event as it gave competitors a cut-off time of 26 hours.


Retrospectively, Mag’s build-up looks calculated and precise. But back in late 2019, the 46-year-old, a seasoned marathoner, hit a rough patch with her running.


After the last Dublin Marathon event, she felt drained and that the marathon distance had become a physical and mental struggle. Although she finished, she decided the ups and downs of running had taken a toll on her and she was done with marathons.


After a month off, Mag – from Enniscorthy in Co Wexford – sought some advice from a friend who pointed her towards David Hogan, a marathon coach. David convinced Mag to give the distance another go. Initially, the training was intense but Mag was seeing results and feeling better for a structured training regime with built-in rest days.


“Your rest days mean you rest. You don’t go do a handy 5k or 6-mile walk. I would look forward to my rest day every week as the other days were long miles.”


Even though her training was going well, her marathon disappointments were not behind her as the lockdown postponed her targeted event, the Manchester Marathon, in April 2020.


As the race calendar in Ireland was effectively cancelled for the rest of 2020 due to Covid, and with Mag not wanting to do an all-out marathon effort during a virtual event, she continued to train and felt: “If there was ever a time for me to give the 100 miles a lash, now is it.”


Over the lockdown, Mag stayed motivated over her long runs by going out with a group of like-minded women known as the Ballymurn Runners. After convincing them to also sign up for the 50 km- event, Mag helped guide the group’s training by posting runs into their WhatsApp group each week.


Between September and April, Mag’s typical weekly distance was between 100 and 110 km. Her longest run during the training block was 56 km on the Waterford Greenway. Her weekly distance target, coupled with a 40 plus hour working week, meant she had to fit her training in whenever she could. Mag seldom had weekends off work so she couldn’t fit in back-to-back runs, a staple training block for many distance runners.


“There were days when I came home from work after being on my feet for 10 hours and the last thing I wanted to do that evening was to go out and run a half marathon, but I wanted that 100 miles so, so bad.”


Her training programme was uncomplicated; clock-up 100 km every week no matter what, with anything additional considered a bonus.


“I just had a focus and that is what I had to get done each week, but it never felt like a chore because I always had company with the Ballymurn girls.”


After six long months, the day finally came and the 100-mile event started at noon on Saturday, October 16. Although Mag’s focus was solely on completing the distance, by 10pm that night she found out she was leading the women’s race.


With the pressure on and nearly 13 hours of racing left, Mag knew she had a tough night ahead of her, made even more difficult by incessant rain. Her pacing strategy on the day was to not drop below a 14 min/mile pace, including any miles where she walked.


“When I knew that I was leading I just said to myself, ‘you are not giving up now. I am going to win this, and I don’t care what happens.’”


The course was a simple loop, with runners from the other events all competing at the same time. The 100-mile competitors were tasked with going around the inside of the track 98 times.


Early on Saturday night Mag was suffering with nausea and thought this might be the end of her race but knew from experience she had to keep eating small amounts of food.


Due to ongoing gastric issues, Mag follows a vegan diet. Her stomach is aggravated by a lot of different food types so she does not take any gels or supplements except the odd protein shake after a long run. She kept her nutrition plan simple during her training.


“I ate when I was hungry. I used to bring extra food to work with me and I would sneak up to the bathroom to eat it.”


Mag was adamant about getting her nutrition right during the event. She did some research into what other runners use to fuel for ultra-distance events and found that TUC crackers and watermelon are a big hit.


Alongside her research, she also relied on Pringles and bite-sized brownies during the race. According to her Strava file, she burned roughly 11,290 calories over the 23 hours, nearly a week’s worth of calories for a normal person.


Mag had been concerned her performance would be hindered by digestive problems that would at best slow her down and at worst be a reason for her to withdraw from the competition. But she got her fuelling right this time and the only time she stopped was when she had to change into warmer clothes or swap her shoes. There were no rest stops.


“I had told my crew unless I was vomiting, and vomiting bad, not to allow me to stop.”


Mag brought a crack team of three to Belfast, her brother and sister in-law, Kieran and Lorraine Sludds, and friend, Orla Doyle. They were tasked with ensuring Mag finished the event by minding her nutrition, keeping her on pace and providing moral support in the tough moments.


“They would come out on the course and tell me, ‘you’ve done so many miles now, you need to come in and eat’ … they were absolutely outstanding with me and with my nutrition, they got everything perfect.”


Mag brought two pairs of Nike Pegasus with her and changed her shoes around 3am after she began to complain that the sole of her right foot was ‘burning’, which later turned out to be a large blister. The other key pieces of her winning kit were simple and inexpensive; a €4.60 pair of track pants from Dunnes Stores and a yellow plastic poncho to keep the rain off.


Between 4am and 5am fatigue had taken hold, and Mag was struggling to keep her eyes open. She began to drift across the track, resulting in her running for an additional 2.5 miles. When she pitted, she begged her crew for five minutes of sleep but was told in good spirit that unless she needed some food, to ‘jog on and keep going.’



Credit Michael Donoghue.


Alot can go wrong in events this long. Digestion issues, injury, exposure to the elements, or plain exhaustion can all stop a runner in their tracks. The deep of the night is often reported as the most difficult part of the run mentally and physically and can be difficult to prepare for in training.


But the tough love and perseverance paid off and Mag finished first in the women’s event in a time of 23 hours and 20 minutes. With the additional 2.5 miles, her actual distance was 102.5 miles (or 165 km).


Mag hopes to go back and defend her title next year, but her priority is to go back to her coach in January and to target two spring marathons.


“My husband told me, ‘when you turn 50 you can do all of the ultra-marathons you want’. I will be 47 next February.”

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