"Mira, you look tired lately."
Sora called out to Mira. In the corner of the library, Mira had her eyes closed with a book still open.
"I'm getting enough sleep," Mira answered softly.
Leo approached. "Physical fatigue and mental fatigue have different mechanisms."
"Different?"
"Yes. Sleep mainly recovers physical fatigue. Mental fatigue is more complex."
Sora opened their notebook. "In psychology, this is called cumulative stress response."
Mira showed interest. "Cumulative?"
"Small stresses pile up," Leo explained. "Each one is small, but when the total exceeds a critical point, you become suddenly exhausted."
"Like water in a bucket," Sora compared. "Each drop isn't noticeable, but when it's full, it overflows."
Mira pondered. "Lately, I have no motivation for anything."
"That might be a warning sign," Sora said carefully. "It resembles early symptoms of burnout syndrome."
"Burnout?"
Leo opened his tablet. "Christina Maslach's research. Burnout syndrome has three elements."
"Emotional exhaustion, depersonalization, and reduced personal accomplishment," Sora continued.
Mira nodded slowly. "I feel like all of them apply."
"Mira, what have you been doing lately?" Sora asked.
"Classes, committee work, part-time job, helping at home..."
"That's all?"
Mira hesitated a bit. "I was also listening to friends' problems."
Leo frowned. "Rest time?"
"...I didn't think about it."
"That's the problem," Leo pointed out. "Cognitive resources have limits. Continuous consumption without recovery causes system collapse."
Sora drew a diagram. "In the stress-recovery model, the balance between stress and recovery is important."
"When stress continues to exceed recovery, mental energy depletes."
Mira said quietly. "But I feel guilty when I rest."
"Why?"
"Because everyone's working hard. Just me resting is..."
Leo shook his head. "That's cognitive distortion. Based on comparison thinking."
"Comparison thinking?"
"Judging your own legitimacy by comparing with others," Sora explained. "But that's based on a false premise."
"False premise?"
"The premise that everyone has the same fatigue threshold," Leo answered. "In reality, individual differences are large."
Sora continued. "Moreover, you can't see others' inner states. Activity level alone can't measure fatigue."
Mira thought. "So how do I know my own fatigue?"
"Listen to your body's signals," Leo said. "Decreased concentration, irritability, listlessness. These are warnings."
Sora added. "Keeping a diary is also effective. Record emotions and activities, and find patterns."
Mira took out her notebook. "What should I write?"
"Three things at the end of each day," Sora suggested. "Fatigue level, main activities, mood. After a few weeks, you'll see trends."
Leo supplemented. "Especially focus on which activities cause the most fatigue."
"What causes fatigue differs by person," Sora explained. "Social interaction that's fun for one person can be the biggest stress source for another."
Mira started writing. "Today... fatigue level 8, too many activities, feeling empty."
"Good start," Leo acknowledged.
Sora asked gently. "Mira, what helps you recover?"
Mira pondered. "...Drawing. Listening to music."
"When did you last do that?"
"Two weeks ago."
Leo was surprised. "No recovery activities for two weeks?"
Mira nodded slightly.
"That's the answer," Sora said. "Without recovery, the heart depletes."
"But I don't have time."
"Time is made," Leo stated. "It's a matter of priorities. Without recovery, all performance declines."
Sora continued. "Remember airplane safety instructions. Put on your own oxygen mask first, then help others."
Mira smiled. "Recover myself first."
"Exactly."
Leo showed his planner. "I block at least one hour of recovery time daily. As non-negotiable time."
"Mira, let's set that kind of time for you too," Sora suggested.
Mira nodded. "Starting tonight, I'll make time to draw."
"Wonderful," Sora smiled.
Mira closed her book. "I didn't notice I was tired."
"Noticing is the first step to recovery."
The three quietly left the library. Mental fatigue is invisible but cannot be ignored. Understanding this was the path to health.