HOW INTERVAL RUNNING CHANGED THE GAME FOR MY TRAINING

Published: 23/12/2025 | By: Tommy Trees

Tommy Trees has spent years pounding the track and the roads, and if there’s one thing he’s learned, it’s that running isn’t just about putting in the miles – it’s about how you run them. Interval training, with its mix of hard efforts and recovery, has completely changed the way he approaches workouts. In this article, he shares his experiences, tips, and lessons from the track, showing how a few focused sessions can make you faster, stronger, and more confident – both on and off the track.

Interval training has completely changed the way athletes and everyday exercisers approach fitness. Unlike traditional steady-state workouts, interval training alternates between periods of high-intensity effort and recovery, pushing the body to adapt more efficiently in a shorter amount of time.

This method has revolutionised performance across a wide range of sports by improving endurance, speed, and mental resilience. As research and real-world results continue to support its effectiveness, interval training has moved from being a niche technique to becoming one of the most powerful and widely used methods in modern fitness.

WHAT IS INTERVAL RUNNING AND WHY IT WORKS

At its simplest, interval running involves repeated high-intensity efforts followed by planned rest or easy recovery. Think hard… easy… hard… easy.

Unlike steady continuous runs, interval training challenges your body to adapt in a more powerful way. It delivers measurable improvements in:

• VO2 max – the maximum amount of oxygen your body can use during intense exercise.
• Running economy – how efficiently your body uses energy at a given pace.
• Lactate threshold – your ability to sustain faster speeds without fatiguing.

Interval training works because it stresses both your cardiovascular and muscular systems in a way that steady-state runs alone cannot. During the high-intensity periods, your heart, lungs, and muscles are pushed to their limits, while the recovery periods allow your body to repair, adapt, and become stronger.

THE TURNING POINT – MY FIRST INTERVAL SESSION

I still remember my first proper interval workout. My father and I went to the local track and completed 10 sets of 400m at what felt like a “fast but manageable” pace. By the second repetition, I was gasping for air, my calves were on fire, and my brain was screaming at me to stop.

What surprised me wasn’t the physical discomfort – it was the mental challenge. But soon after the session, the endorphins washed away the pain and left me buzzing with energy. I was hooked. That workout became the turning point in my running journey. For the first time, I realised that I could push past perceived limits and actually come out stronger on the other side. From that day, interval training wasn’t just a workout; it was a game-changer that transformed how I approached every run.

That confidence carried into races and hard training days. I became more comfortable with discomfort, which is one of the biggest mental advantages a runner can have. Interval training taught me that I could handle more than I thought – not just in running, but in life.

THE SMALL WINS THAT SNOWBALLED

Once I committed to consistent interval running, the improvements started stacking up:

• My 5K time started to get quicker and quicker.
• Easy runs began to feel significantly more comfortable.
• Interval sessions became much less daunting.
• My form felt more controlled at faster speeds.

I didn’t need perfection. I just needed small improvements, repeated over time. That’s one of the most powerful lessons interval training taught me.

HOW I STARTED AND HOW YOU CAN TOO

If you’re new to intervals, here’s a simple format that works:

1. Warm-up: 10 to 15 minutes of easy jogging and mobility exercises.
2. Intervals: Hard efforts followed by steady recovery.
3. Cool-down: 10 minutes of relaxed jogging and stretching.

My beginner interval plan:

• 8 x 400m at 5K pace, with 90 seconds rest between repetitions.

Progression over time:

• Add more repetitions: 10, 12, 14 x 400m.
• Reduce recovery: 75 seconds → 60 seconds → 45 seconds.
• Increase distance: progress to 600m, then 800m, then 1000m.

Tip: Track your effort, not just your pace. Some days won’t feel great – that’s part of the process.

Suggested Kit

You don’t need fancy equipment for interval training, but the right kit can make a big difference:

• A lightweight, supportive pair of running shoes to protect your joints during faster efforts.
• Comfortable, breathable clothing to help regulate your body temperature.
• A watch or phone with a timer, plus a secure armband or belt to hold it in place.
• Reflective gear and a lightweight jacket if training outdoors in low-light or changing weather conditions.

A simple, practical kit like this keeps you focused on your intervals and maximises the effectiveness of each session.

WHY RECOVERY PERIODS MATTER

Recovery periods in interval training are just as important as the high-intensity efforts. They are what make interval training effective rather than simply exhausting.

1. Recoveries allow your heart rate and breathing to partially return to normal, making it possible to repeat multiple hard efforts in a single session.
2. Recovery time helps your body adapt. During rest, your muscles clear waste products like lactate and begin repairing tiny muscle fibres, leading to increased strength, endurance, and speed.
3. Recoveries train your body to become more efficient at bouncing back. Over time, your heart, lungs, and muscles learn to recover faster, improving performance in both intervals and races.

HOW INTERVAL TRAINING TRANSFORMED MY PERFORMANCE

When I first started interval training, my main goal was to break the 20-minute barrier for the 5k. Until then, I had relied mostly on steady and easy runs. While these built endurance, my pace had plateaued.

Once I introduced structured intervals, everything changed. My body adapted quickly to running at higher speeds, my confidence grew, and races began to feel more controlled and manageable. Within a few weeks, I went from struggling to break 20 minutes to running a 19-minute 5k – and soon after, an 18-minute one. Interval training didn’t just make me faster; it completely transformed the way I ran and approached racing.

PROGRESS OVER PERFECTION

My final tip for anyone starting interval training is simple: focus on consistency over perfection. You don’t need every session to be flawless or hit every interval at exactly the same pace. What matters most is showing up, putting in the effort, and building the habit over time. Stick at it, trust the process, and the improvements will follow.

Interval training rewards patience and persistence, so keep going and enjoy the journey!