It took less time than an average lunch break for world champion boxer Mea Motu to leave me physically spent, mentally broken and unable to lift my arms properly for a week.

She did it with a smile on her face.

The super bantamweight world titleholder – shortly after announcing her upcoming fight in Whangarei, and not long after she defended her title with a dislocated shoulder – agreed to let me train alongside her.

Walking into West Auckland’s Peach Boxing on a drizzly Monday morning, I heard the 33-year-old champ before locking eyes on her.

In the back of the warehouse gym – the logo of which is etched permanently in ink on her neck – she was firing shots at the pads of 8-year-old trainer, Zen (who has just turned 9), hissing with every exhale. Each quickfire blow was met with a loud crack as it hit the young boy’s pads – a sound that seemed to echo through the concrete-floored gym.

It was an intimidating noise. Still, I wrapped my hands with naive confidence.

I’m just a journalist, after all. I’ve jumped into a few awkward situations in the past – many spurred by my boss being hit with a “fun” idea. Surely the pro – whose muscles protrude from every inch of her diminutive figure – would take it easy on an out-of-shape 42-year-old who hasn’t trained combat sports in close to a decade.

“No chance,” Motu said with a wry smile before an impatient-looking Zen called us onto the gym floor to get stuck in. He may have looked unassuming, but this young badass didn’t take kindly to slackers.

The next half hour was a brutal assault on my severely under-trained lungs and endurance. I was on the floor for the final time that morning, struggling to breathe properly, mourning the loss of full use of my shoulders, and regretting every time I’d casually put off cardio training until tomorrow.

“Tomorrow” had finally arrived. And it hurt like hell.

I’m neither graceful nor gutsy enough to be a fighter. When learning Muay Thai kickboxing a decade ago, I was told by the trainer I had a “Forrest Gump leg thing going on”. I cried the first time I landed a punch on someone’s face.

That discomfort had not magically dissipated after years of not training. I learnt this quickly when Zen declared it was time for “light” sparring.

“Hit me anywhere, keep going,” Motu encouraged, giving me multiple chances to take a shot before lightly throwing jabs my way, that I tried valiantly – but failed miserably – to dodge.

“Hit me like you did the bags,” she said, always moving – light on her feet – before tossing another jab at my glove. It was a light punch, but caught me unaware, and I hit myself in the face.

My lungs were burning, I was broken, exhausted and frustrated over being unable to land any kind of punch on someone much faster, fitter and much better than me. None of those feelings are remotely helpful in a sport that relies on discipline and controlled emotions.

And then there was that extreme discomfort when trying to actively hit someone.

The more frustrated, tired and sore I got, the more wayward punches I’d miss, as Motu easily danced around me, throwing quick jabs, refusing to let me pause to catch my breath.

In case there’s any doubt – journalist turned professional fighter is a very unlikely career trajectory at this point.

Zen, our young taskmaster, worked us through a few areas of the gym – plastered floor to ceiling with fight posters, with rows of heavy bags lining the walls.

Punching bag rounds seemed a never-ending cycle of body or power shots, jabs and hooks and speed drills before finally being given the call of “time”, barely allowing a moment for water before dragging my already-heavy shoulders to the next station.

Each time I figured we must almost be done, Zen would reset his timer for another go. We worked through heavy bags and speed work. Zen held pads and I managed to land a few hits with a satisfying crack they give off when you aim just right. “Cool down” rounds of shadowboxing with Motu – practising light jabs that don’t connect – was a very awkward waltz for someone heavy on their feet with no grace.

Cries of “faster” and “keep going” or Motu’s encouraging “use your hips” sandwiched between intimidating hissing did little to help. My shoulders had nothing left to give.

The morning became a blur of never-ending rounds of pain. At one stage, as Motu and I alternated speed punches, I could hold the bag steady only by collapsing myself into it – forearm-shaped sweat marks a clear indication of how far gone I was.

My “power” punches had no power. When I stopped for a breather, Motu demanded I keep going. All I was capable of in response was a grunt. I put my head down and tried not to think of how much I’d suffer in the days following.

But despite the exhaustion, the pain and the inability to lift my arms once it was over, I was left buzzing. I emerged from the pain cave – exhausted enough for my boss to look a little concerned – but filled with smile-inducing endorphins.

Motu, who will take the ring again in the first weekend of December, is a fierce competitor in the ring. But outside was welcoming, encouraging and an absolute badass.

I – having finally regained full use of my shoulders – can only wait, a little apprehensively, for the next “fun” idea to land on my desk.

Motu will defend her title on December 2 in a doubleheader at the Whangārei’s McKay Stadium.