As I leaned against an exercise ball pressed against a wall in a seating position with no seat, I felt my legs slowly begin to give out. The ball began to drop as I watched my legs quiver—first the left, then the right—as a fiery sensation filled my thighs.

I looked to my right, where a man with a left thigh as big as both of mine together, sat there calmly against his ball. The instructor—a petite woman in her 60s with toned arms and curly dirty blonde hair—counted down into her microphone. Much like the man next to me, she seemed unabated by her seated position.

She seemed harmless enough when I first walked into the studio for a morning Muscle Blast class. But in that moment of burning legs, dead arms and a mind screaming “STOP, YOU IDIOT!” there was no one I hated more.

“Five more seconds,” she called out over her microphone.

Five more seconds felt more like a minute as I looked down at my trembling legs, looking like I was trying to do the stanky leg than sit in an invisible chair of burning hell.

Four…

Three…

Two…

One.

Not even a second after she said one I pushed myself to a standing position as the blood rushed back through my legs, feeling like a thousands red fire ants simultaneously bit into my thighs.

That was it. I was done. I’d reached my max workout and was ready to walk out of the studio when I noticed the instructor and the rest of the class leaning back against their exercise balls doing another crazy version of squats.

“Oh, fuck that,” I mumbled under my breath.

The man next to me laughed.

“Don’t give up on me now,” the instructor said to no one in particular. But I knew—she was talking directly to me.

The burn in my legs subsided long enough for a brief moment; long enough to convince myself that I could do a few more exercises before calling it quits. Right as I pressed my back against the ball, I felt the burn return and more intense than before. Not only did it feel like fire ants were biting every inch of my thighs, but it felt as if someone had lit the ants on fire, both pissing them and causing them to bite harder, and burn my legs into charred mush.

How could this woman, who seemed like such a wonderfully nice lady, cause so much pain?

“Only five more,” she called out again.

“Only three more until my legs fall off,” I thought.

Four….

Three…

Two…

One.

At the end of the exercise, we retreated to blue mats on the floor to wind down our workout with various yoga stretches and light exercises.

I ignored her call for planks, push-ups, crunches and sit-ups and laid there having met defeat in the form of a 60-year-old woman who just kicked my ass.