I am woefully out of shape. Naturally, then, I was the one sent out for an exercise session just after the stroke of midnight.

While thousands of people have taken up running or HIIT training with Joe Wicks during lockdown, I've been sat on the sofa watching films.

Therefore, I was filled with apprehension over the entire weekend as I replayed a conversation I'd had with the team at Kingsmead Leisure Centre on Friday.

“Just how difficult is it going to be?” I muttered down the phone. “I haven’t exercised for at least four months.”

My inquiry was met with a chuckle, before the Canterbury sports facility’s communications officer said: “I think it’s going to be quite lively.”

And then I read more about the class - the first to be held indoors since restrictions were relaxed. It was set to include activities called “body attack”, “body pump” and “body combat”.

By the time I stepped out of my car and towards the leisure centre on Sunday night, I was racked with worry that I’d either pass out or end up unloading the contents of my stomach. I was ushered inside and told I needn’t wear a mask indoors.

Cool air wafted through the open doors at both ends of the hall. Bits of white tape were stuck to the floor, delineating the socially-distanced squares in which each member of the group should stand. I made a beeline for one tucked away at the back of the room and waited for the hour-long class to begin at 12.01am.

The event was being held in memory of former Kingsmead Leisure Centre general manager Jonathan Wake. The 56-year-old died just three months after being diagnosed with a brain tumour in March 2020. Each participant paid £5 to take part, which will be donated to charity.

After the last of the 40 or so people taking part ambled in, it started. One of the instructors at the front facing us blasted out commands through a microphone, while up-tempo music resounded through the hall.

“Stand side on. Elbows in. Hooks! Four uppercuts,” she bellowed.

“Four, three, two, one, down and jab. One more. Turn! And push.”

Feeling stiff and uncoordinated, I tried to follow the instructions, but quickly found myself out of step with everyone else in the room. Despite this, I was having fun.

We were then told to kick the air in various ways, in between skipping around our boxes, running on the spot and other fast-paced activities. But soon enough, my lack of fitness caught up with me as my movements became ever more ungainly.

When we were told to start doing burpees, my attitude changed. Instead of lapping it all up, I was wishing for the next water break to come and my breathing grew increasingly laboured.

I felt light-headed and attempted to grab breathers at every available opportunity, patting myself on the back for sticking myself in the far corner of the hall. I looked on despondently as almost everyone else continued to bounce around with brio.

“Get your bars now,” another instructor announced.

In front of each box lay a barbell, with a pile of light weights that needed to be attached at either end.

“And squat. Three, two, one and up. Shuffle wider. Let’s go. Get deep, and hold," she said, as the music continued to blast out of the speakers.

"Push. Reset. Again."

I struggled on, my mouth hanging open as I staggered up and down. However, I took pauses with even greater regularity and found myself completely out of step with the rest of the class – I was dipping when everyone else was rising and standing as they squatted.

Soon enough, we were alternating between bicep and triceps curls, before concluding with balancing exercises. By this point, I was a quivering mess unable to support my own body weight, stumbling over whenever we were told to stand on one leg.

And then, it was over. The class dispersed and we all made our way out into the 1am gloom. I waddled towards my car, my legs stiff with tiredness. As I guzzled water from my bottle, I noticed my sweat-soaked clothing sticking to my skin.

But as I reflected on the last hour and my embarrassingly feeble efforts, I wanted to do it all again. It was tremendous fun. Maybe I’ve turned a corner.

• The proceeds of the class will be given to charity Brain Tumour Research. For more information, visit www.facebook.com/challengesforjonathan/.

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