How to run 5k faster with intervals

How to run 5k faster: “Nailing interval training improved my 5k time in just 4 weeks”

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Looking to beat your 5k personal best? It took writer Megan Geall just four weeks to improve her Parkrun time – and she claims you can do it too.

If you told me before Christmas that I would cut down my 5k time by almost a minute in just four weeks, I would have laughed. And yet, a month on, I’ve done it – almost entirely thanks to nailing interval training.

Every week, I take part in Parkrun, a 5k run (or walk) around a local park. Not only does Parkrun get me, my mum and my sister up at 9am on a Saturday morning (crazy, I know) but it also gives us an amazing sense of achievement when we come panting over the finish line, clocking our times. We’ve all fallen in love with running and it’s become something of a weekend ritual.

I decided to add one interval training session into my workout plan after my times plateaued. Interval training is all about putting your cardiovascular fitness to the test by switching up how hard you work. Instead of going out for a 30-minute jog, you might choose to do eight 200m sprints (for example), followed by a minute’s walk or very slow jog to recover. 

My experiment began with the New Year’s Day Parkrun. While I was definitely hungover from one too many glasses of prosecco, my run was enjoyable, and I completed it in 23:23 – pretty much the same time that I’d been getting for umpteen weeks.

Week one: getting to grips with intervals

In a bid to break that impasse, I set out to do at least one session of interval training each week – which was definitely a struggle to begin with. I’m more used to running longer distances slower, so switching things up and running fast for short periods took a lot of getting used to. 

It was hard, but after a few minutes, I actually started to enjoy the sensation of raising my heart rate before letting it recover in my rest periods.

That first Saturday quickly came around and I was ready to get back to my longer runs. I completed Parkrun in 23:11 – a new PB. I didn’t feel particularly different during my run although I was more aware of my breathing. The interval training had made me focus on controlling my breathing as I was running at a higher tempo during the sets. 

Week two: struggling to build speed

By the time I reached my second week of intervals, training had become a real chore. Everything about it felt unnatural as I struggled and failed to get into a comfortable stride. 

My run that Saturday morning started off frustratingly. It was a very cold morning with ice on the paths and a lot of runners had turned up to Parkrun, so it took longer than usual for everyone to spread out.

Despite these difficulties, I was shocked to see I got another PB. I wasn’t particularly focused on pushing myself for a fast time as the main aim was to avoid slipping on patches of ice. The longer I ran, however, the more my confidence grew and while I didn’t have energy left for a final sprint, I ended up almost breaking the 23 minute mark. 

Almost as soon as Megan started adding intervals to her weekly agenda, her 5k time improved.
Almost as soon as Megan started adding intervals to her weekly agenda, her 5k time improved.

Week four: picking up the pace

For the final week, I decided to make my training more difficult. I increased the pace of my rest periods to a slow jog instead of a walk, and that reduced recovery made the overall session a lot harder. Still, I was shocked to notice how much my stamina had improved in such little time.

By the time that final Parkrun rolled around, I was determined to push myself harder than ever (after all, I’d got three PBs under my belt with little effort – how much faster could I go if I really tried?). I started quicker than normal and with each lap, tried to increase my effort. By the end, I was exhausted. And I was relieved to find out that I’d run my fastest time ever, at 22:31: 52 seconds quicker than on New Year’s Day.  

Running is a great way to exercise but it can be frustrating if you don’t feel like you are making any improvements. Interval running is the perfect training technique to challenge yourself and get results.

Online coach and personal trainer Charlotte Lockett suggests that interval training is a great tool for any runner: “Since interval training is highly customisable, anyone who can safely jog or run can do it,” says Lockett. “If you are just starting out, I would recommend a longer warm up to avoid the risk of injury, and then aim to increase work and decrease rest ratios during each session.”

A 2020 study into the effects of HIIT, published in the International Journal of Environmental Research and Public Health, found that this kind of training is “a time-efficient means to improve CRF [cardiorespiratory fitness] in as little as two weeks in adults”. As a form of HIIT, interval runs can help to increase your cardiovascular fitness and improve your stamina, power and endurance.

Hannah Walsh, women’s ultramarathon running coach, tells Stylist that “interval training is a good complement to easy base running”. However, one of the most common mistakes that beginners make, she warns, is “not balancing the interval running with lots of easy mileage. It shouldn’t be considered a shortcut to fitness or a standalone method of training”.

While I definitely prefer my longer runs, interval running provided me with a fresh method of training that challenged me in new ways. I can’t say that I’ll stick with doing an interval session every week, but I’ll definitely come back to it, should my Parkrun times plateau again. 

For more running tips, visit the Strong Women Training Club.

Images: author’s own

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