Natural Shape
I ran, chasing after Seora noona's back.
"Heok, heo-eok."
Maybe because I'd slacked off on exercise for a while, my breath caught up in an instant. My breathing was off and my throat ached.
Seora noona, having slowed down, came up beside me and said,
"Don't breathe only through your mouth. Didn't I tell you?"
"Yeees!"
"Your stamina's really tanked. Let's run to that bench over there and take a short break."
When we reached the bench, I gulped down the air that had surged to my throat. Then another round of nagging flew in.
"Don't pant through your mouth, breathe slowly. Inhale, exhale."
"Hoo, haa."
"That's it."
Seora noona became quite strict when exercising. But if I did as she said, the effects were clear.
Once my breathing had calmed down somewhat, Seora noona clicked her tongue (tsk tsk) and gave my back a light slap.
"It's because you took a break."
"I only rested for a week..."
I felt a little wronged. After busting my ass for two whole months, to end up like this just because I rested a measly week.
"That's how the human body is. Just when you think you've adapted, if you rest even a little, you quickly revert. Building muscle is hard, but gaining fat is easy."
"The human body is really inconveniently made. If there's a god, they definitely messed up."
"Ahaha. I think so too. Still, it's better than when you first started running, right?"
Well, that was true. My stamina had dropped compared to a week ago, but compared to when I first started running, I was practically a different person.
"Alright, run again!"
"Whaaat? Let me rest a bit more!"
"You've rested plenty. You can't rest until your body cools down. Now, run!"
"Uwaaaaah!"
Seora noona pushed my back forcefully, so I had no choice but to run. Just when I thought my breath had returned, I was miserable again.
Seora noona ran a little ahead of me. Running side by side supposedly didn't help. She said it was more efficient if I ran so as not to lag behind the person in front. I ran like a horse chasing a carrot, watching her ponytail sway left and right.
It was hard, like my heart was going to burst, but it wasn't all bad. As I ran, mesmerized by her ponytail, I naturally caught sight of other parts too.
A twitching butt.
Even though she was wearing joggers, her well-defined glutes were visible. Maybe because she was an athlete, they had an incredible lift. I felt sorry for her, but I squeezed my stamina to the limit, using my perverted drive as fuel.
*
An Seo-ra glanced back. She saw Kang Cheol-jin chasing after her as if his life depended on it.
"I have to admit, he's impressive."
His mental strength was even more impressive than his stamina. Even though she pushed him to the brink, the way he tried to keep up somehow looked endearing. So she ended up picking up the pace a little herself, and he still chased after her frantically.
'He's a different person compared to the beginning.'
Who would see that and remember the weakling from the first day? It hadn't even been two months since they started running together, but he'd improved so quickly.
Was he originally athletically gifted? Anyway, since he followed her teachings well, he was a rewarding newbie to teach. It also felt like walking a large dog.
"Hmm. Though his motives seem a bit impure..."
She wasn't oblivious to Kang Cheol-jin staring intently from behind. At first she hadn't noticed, but with that intense gaze, she couldn't miss it.
It was a bit cheeky, but she didn't bother to scold him. She figured if that motivated him, then it was all good. It wasn't like it was the first or second time men stared at her body.
An Seo-ra was used to men's gazes. In both good and bad ways. So Kang Cheol-jin's gaze didn't really bother her that much.
Still, it was cheeky all the same.
"N-Noona, you're too fast!"
"No, you can run more."
She upped the pace. Just enough for him to be on the verge of passing out. If he still had the wits to stare at her butt, he wasn't at his limit yet.
*
"Ughhh..."
Groaning like a zombie, I collapsed onto the bench. Now I really couldn't run if my life depended on it. Maybe as punishment for skipping exercise, I ran twice as hard as usual.
'I feel like we ran 10km...'
It wasn't an exact figure, but since we ran twice as much as usual, that was my estimate. It took almost an hour to finish.
Meanwhile, compared to me gasping for air like I was dying, Seora noona only had slightly ragged breathing. She wiped her sweat with a towel, drank water, and smiled as if she felt refreshed. What the hell, that workout freak...
At that level, shouldn't she be doing marathons? I think I heard she's in the Sports Science department, but from the way she runs, she's a talent who should be a competitor, not just support.
"Noona, don't you participate in marathons? Seeing you so relaxed after 10km, I think you could even place."
"Huh? What are you talking about, we only ran 9km."
That's basically the same, isn't it? I stared blankly, and Seora noona chuckled.
"People who are really good run 10km in under 40 minutes. Athletes do it in around 30 minutes."
"They're monsters..."
"Well, I can do about 40 minutes if I run properly. Since the topic came up, want to prepare together? I've wanted to try participating in a marathon."
"Heek. I'll pass."
I bolted upright and waved my hands. I ran 9km in an hour and felt like dying, and she wanted me to compete? I immediately envisioned a future of puking while running.
Seora noona smacked her lips as if disappointed. It gave me chills how genuinely disappointed she seemed.
I decided to change the subject. I had a favor to ask her anyway.
"Forget the marathon, could you teach me some exercises?"
"Huh? Exercise? Other than running?"
Seora noona's eyes sparkled. Seeing that was a bit scary, but I had made up my mind, so I continued.
"Weight training. Lately, just running has been a bit boring, so I want to switch things up. Oh, of course, I'll pay for the PT."
Seora noona was a professional trainer with Level 1 fitness and rehabilitation certifications. She said she works as a trainer at a gym after her school lectures.
"Of course! It's normal to get bored repeating just one thing. Good thinking. The most important thing for a beginner is consistency."
Seora noona nodded enthusiastically. She was totally excited. I was a little worried, wondering if I'd made a mistake...
"Let's go right now!"
"Y-Yes? Right now?"
Seora noona grabbed my arm. Flustered, I asked again, and she said firmly,
"We have to go as soon as it's mentioned! You have afternoon lectures today, right? I know your schedule, so don't think about running away."
...It wasn't the time to worry. I'd already been bitten.
Still, I made one last desperate attempt and hurriedly said,
"N-Noona. From tomorrow..."
"Come on, I won't make you work hard. Let's just give it a try."
"Isn't the gym not open yet? It's only 7!"
"It's a 24-hour gym. And since I'm a trainer there, I can get in even when it's closed."
"...."
I gave up. Running away was already impossible.
I was dragged along, arm in Seora noona's grip.
*
When we arrived at the gym.
"Whoa... there are people here at this hour."
I saw more people than I'd thought. Even roughly counting, there were nearly ten.
"Of course. There are people even at dawn. Some exercise in the morning before going to work."
"That's amazing, for real."
I'm just a college student, but I can't help but respect office workers. A day of work alone must be tough, yet they still exercise.
The gym Seora noona brought me to was incredibly spacious. It spanned multiple floors. Racks, machines, spinning rooms, and stretching rooms were all separately equipped.
"Since it's your first time, shall we measure your InBody first? Go to the bathroom first. You have to empty your bladder to measure."
"Yep."
I went to the bathroom and then climbed onto the InBody machine. She said it was convenient to link the app, so I immediately downloaded it and entered my height and age.
"Don't let your armpits touch, and don't talk."
"Yep."
"I said don't talk."
"...."
I shut my mouth and the numbers started appearing.
The immediately visible ones were weight and body fat percentage.
[Weight 96.3kg]
[Body fat percentage 26.2%]
Embarrassing. Still, I thought since I'd been exercising for a year, I'd be under 25%, but no way.
As I recalled, the average body fat percentage for men in their 20s was 15-20%. Around 15% apparently shows you've exercised quite a bit.
"This is serious, isn't it...?"
I asked, slightly crestfallen.
"What are you talking about? It's way better than I thought. Cheol-jin, why do you have so much muscle?"
A completely different reaction from what I expected came back.
"R-Really?"
I asked again with a slightly dubious expression. Was this noona just trying to console me?
But Seora noona spoke with an expression even more surprised than mine.
"Yeah, for real. At this level, you're not really obese. Cheol-jin, it's just because you have a lot of face fat, but your body fat is lower than I thought."
"?"
My body fat came out over 26%, so I didn't know what she meant. As I blinked with an expression of incomprehension, Seora noona pointed to the printed sheet and explained.
"Look, if you just look at BMI here, it does say obese."
"Yeees..."
The paper had BMI values marked by ranges.
Underweight, normal, overweight, obese, severely obese.
My BMI value was pointing all the way to the right even within [obese]. If my weight had been just 1kg more, it would have been classified as severely obese.
But Seora noona still had a bright expression. No, she even looked a bit excited. Her eyes sparkled at me in a way that felt overwhelming.
"But actually, BMI isn't a very meaningful number. It's measured purely by weight relative to height."
"Uh... is that wrong?"
"There's a lot of debate about its measurement method. Think about it. Even with the same height and weight, people can look completely different. That's all because of muscle mass differences. But BMI doesn't account for muscle mass and classifies obesity based only on height and weight. Is that really accurate?"
"Ahh!"
I understood clearly.
Let's consider an extreme case.
There are two people, 180cm tall and weighing 90kg.
A is someone who has never exercised in his life, and B is someone who has exercised all his life.
The two are the same height and weight, but their bodies are completely different. A is pot-bellied with thin limbs, while B has broad shoulders, thick arms, and visible abs.
Since the two have the same height and weight, their BMI values are the same, but the actual visible appearance is completely different.
"So what really matters is muscle mass and body fat. But you, compared to your weight, have a lot of muscle and low body fat. Originally, with your height and that weight, having over 30% body fat wouldn't be surprising."
"Ooh..."
I felt proud, thinking that my efforts over the past year weren't in vain. At this level, wasn't I in the normal range?
But it seemed I was beyond just that level.
Seora noona looked me up and down and asked,
"Did you do separate strength training? Or is your frame naturally built? How is your skeletal muscle mass over 42kg?"
"I did some home workouts. Push-ups and pull-ups."
A health channel I enjoy watching on Wetube once introduced a push-up and pull-up program. Based on that, I had been doing push-ups and pull-ups.
"Every day?"
"Not every day, just often..."
"How many push-ups can you do at once?"
"Nonstop, about 60?"
"...Pull-ups?"
"Ah, I can only do five pull-ups."
"...."
Seora noona looked up at me silently. Was that too few after all?
I was starting to feel a bit embarrassed.
"Cheol-jin, take off your top for a moment."
"Okay... wha—?"
Reflexively, I crossed my arms over my chest.
"Here?"
"Yeah. Don't mind others. There aren't many people anyway."
"No, but still..."
"I'm just trying to check something."
"Yees..."
Is taking off your top something people normally do? I thought it was just to show off in Wetube videos.
Anyway, I took off my top while glancing around, but surprisingly, nobody paid me any mind. Seems it really is a common thing.
'I was a bit embarrassed, but it's a relief.'
Of course, it was still embarrassing, taking off my top in front of a woman. I wasn't that embarrassed during sex anymore, but doing it at the gym felt different.