I added these four basic core moves to my training schedule for 30 days—here’s what it did for my running

Despite my love-hate relationship with running, I’ve picked it up again in the last month—with the lighter evenings motivating me to get outside.

The last time I ran regularly was in January 2025, when I did a mile a day charity challenge for the Motor Neurone Disease Association.

Since then, I’ve been fairly inconsistent, doing the odd 5K Parkrun along the beach at my mum’s place in Exmouth or the 2km junior Parkrun with my daughters in Oxford.

I’m not a natural runner, but I started again a few weeks ago, aiming to run at least once a week, hopefully twice, for around 30 to 45 minutes, and my favourite route is a 3km run along the towpath and river near my house. Looking at the wildlife and scenery helps distract me!

I do a regular run every Wednesday lunchtime with my good friend Amy, and I’m hoping to do a few longer runs now that the weather is warmer.

But I know that the secret to becoming a better runner—and enjoying it more—is to include exercises that support running in my week, too.

As well as traditional strength training, runners should do core work, which aids balance, good posture and reduces the risk of injury.

Although I regularly tell my personal training clients what to do to build core strength, I don’t always dedicate enough time to it myself.

So, I decided to make a conscious effort to add a short core workout to my usual exercise regime, focusing on four essential core moves for a month—choosing the plank, side plank, dead bug and Russian twist.

I chose the plank because it works the transverse abdominis, one of the biggest abdominal muscles that supports and stabilizes the spine and pelvis. Strengthening that muscle should promote an upright running posture.

The side plank hits the obliques (colloquially known as the side abs) and glutes. Glute strength is important for runners because it helps generate speed, power and keeps the body upright so you are balanced when in motion.

The dead bug made my list because it involves moving the opposite arm and leg at the same time, mimicking the movement pattern of running. It also works the deep core muscles, helping improve stability and balance.

I wanted to include the Russian twist because it’s a rotational move that strengthens the obliques and deep core, which helps reduce excessive rotation from the torso when running, to save energy.

I aimed for 10-15 minutes a day to build up core stability—I generally did the workout as a standalone circuit before the kids got up for school, working my way through each exercise for 40-60 seconds.

I continued aiming for two runs a week, and at the end of the month, as well as being able to hold a plank for longer, the mini core workout had a positive effect on my running performance. Here’s what I discovered after 30 days.

My running posture improved

Before starting my core training challenge, I had noticed that when I tried to run further than my usual 3km riverside route I tended to slump forward a bit when I got tired.

But the core strength I built up from doing planks and side planks for a month really made a difference to my runs.

I found that I was able to maintain a good upright position, and my running stride was more consistent and efficient.

In the past, I think I’ve stepped too far forward when running (overstriding), especially when I’m getting tired, and this is probably contributed to those occasions when I’ve ended up rolling my ankle or tripping over something.

I felt that being more stable and stronger in my core helped me to run more efficiently, and not overstride—a common mistake new runners make.

Having not done side planks for ages, when I first started, I could only hold the position with good form for 30 seconds or so, but by the end of the challenge, I was able to stay up for over a minute.

I felt less injury-prone

I don’t want to jinx myself by saying this out loud because I’m naturally clumsy, but doing 30 days of core training—particularly exercises like the dead bug that involve control and coordination—made me feel so much more confident when I ran because I felt less injury-prone.

Previously, when I’ve run consistently, I’ve had issues with my left knee and hip. I’ve also had a few cases of twisting my ankle, which has put me off making running a habit. I wondered if my weak core had also been making injury more likely, so I spoke to a professional to find out more.

“The core’s job is to provide stability to your spine and pelvis so you can generate power in your arms and legs,” says Dr Ashley Katzenback, physical therapist and owner of Cape Concierge Physical Therapy.

“For runners, a weak core prevents sufficient power generation for forward propulsion, leading to excessive shear force through your pelvis and hips, which translates down to the knees.

“If our core is weak, we will land on our heel instead of our midfoot. This will put excessive impact through our knee, potentially causing it to give out or buckle under the load.”

By week three of core training, I realised I felt more stable in my stride, and I also had more confidence, too. I used to start every run assuming that at some point I’d trip and/or roll my ankle, but this fear soon faded.

I felt less tired at the end of a run

As a fair-weather runner, I often felt overly tired by the time I got home from a run—probably because I wasn’t doing it often or consistently enough.

My realisation after 30 days of core training is that rather than me not being cut out for running, I was just doing it inefficiently.

It’s fair to say that I could just be getting better at running because I’m doing it more often, but I also just feel like I’m doing it better. I’m more upright, I’m less clunky in the way I move, and I finally feel like I’ve found my running rhythm.

When the core is weak, you move and twist your torso a lot more during a run, which wastes energy. But a strong core helps you maintain good form, so your energy and effort are put into propelling you forward instead.

This was one of the top benefits of my core training—but it didn’t happen overnight. I’d say it was at least two weeks before I noticed a difference, and then I built on that week by week.

Bonus: It also stopped me slouching at my desk

Working as a freelance fitness writer means I’m often sitting at my desk for long periods without moving.

I’m terrible at sitting up properly, and over the day I tend to naturally slip down my chair or sit on my foot—or another awkward, back-bending posture.

But within two weeks of my core training challenge I found I was sitting up taller, not slouching as much, and paying more attention to how I was sitting. It’s also worked wonders on the neck and shoulder ache I used to get at the end of a shift.

I’ll definitely be keeping up with the core training beyond the challenge. I really feel like it’s helped me run better and, to an extent, enjoy it more—I’m still working on trying to love running!

To keep challenging myself, I’m going to add some resistance to the exercises, and plan to include more rotational moves, such as the wood chop, to work on mimicking the torso’s natural twisting motion when running.

The four core exercises

1. Plank

Time: 30-60sec

• Get on your hands and knees.
• Engage your core.
• Place your forearms on the mat, with your elbows directly under your shoulders.
• Step your feet behind you.
• Hold your body in a straight line.

2. Side plank

Time: 30-60sec

• Lie on your right side, propped up on your forearm, with your elbow directly under your shoulder, and your left foot on top of your right.
• Lift your hips so your body forms a straight line from your head to your feet.
• Keep your other arm by your side or stretched toward the ceiling, and hold.

3. Dead bug

Time: 30-60sec

• Lie on your back, with your knees raised and bent to 90°.
• Extend your arms up.
• Engage your core to gently press your lower back into the floor.
• Slowly extend and lower your right leg, and lower your left arm behind your head, until your right foot and left hand are just above the floor.
• If your lower back rises off the floor, stop lowering your leg just before your back lifts.
• Return to the start with control and then repeat on the other side.
• Continue, alternating sides for time.

4. Russian twist

Time: 30-60sec

• Sit on the floor with your knees bent and your heels on the floor (or hovering just off the floor to make the exercise more challenging).
• Lean back, forming a 90° angle between your torso and thighs.
• Extend your arms in front of you at shoulder height.
• Keeping your knees and hips still throughout, rotate slowly at your waist to move your hands to one side.
• Pause, then return to the center.
• Repeat on the other side.
• Continue, alternating sides for time.