Takuma wheezed as he ran around the farm with the weighted vest, ankle and wrist weights that were more like demons trying to pull him into hell than training aids. A burning and painful amount of lactic acid had built up in his muscles, and after a mere two hours of running with the weights on his body, he was finding it hard to lift his legs and swing his arms. He could sprint for a good chunk of the day, but the weights had slashed all of that to a less than two hours.

He was so slow that while he was trying his level best to run, Anko was keeping up with a light jog. She had been supporting (prodding) him to keep going despite his request for breaks. She had refused all of his requests other than his requests for water.

"Why are we doing this?" asked Takuma, unable to contain the whining tone.

"Finally. I was expecting to get the question an hour ago. You endured beyond my expectations," she chuckled. "Think about what that says about you—you may or may not like that about yourself.

"And to answer your question, let me pose one to you. It's quite simple. What is chakra made of?" she asked.

"… It's a product of two components found within every living being. The Physical and Spiritual Energy which fuse together to produce chakra," he answered.

"Correct," said Anko. "To increase your chakra reserves, one must increase the Physical and Spiritual Energies to be able to create a higher amount. It's simple math. Next question: How can you increase your Physical and Spiritual Energies?"

Takuma spoke with difficulty as he continued to run. "Physical Energy is collected from each of the body's cells and can be increased through training and exercise. To increase Physical Energy, you have to develop your body. The more you train your body, the higher amount of Physical Energy you will have."

According to the prevalent chakra theory, a person's Physical Energy would gradually develop naturally from birth until they reached physical maturity in their mid-twenties. They would remain at that level for the next five to ten years before deteriorating as they grew older.

People who exercised or trained their bodies to extract their body's potential would have much greater amounts of Physical Energy. Shinobi who used chakra and trained their bodies extensively could extend their peak and retain their peak physical potential beyond what was possible by normal people.

But the Physical Energy demanded effort.

Lack of exercise deteriorated physical health, which affected Physical Energy. A peak human specimen at the height of pure physical performance would start going out of shape within two weeks if they stopped training— which would decrease the amount of Physical Energy they possessed. To have the highest possible amount of Physical Energy, a person needed to be in tip-top shape.

Physical Energy was also affected by injury and disease. An unwell body caused a decline in Physical Energy.

Takuma continued, "Spiritual Energy is derived from the mind's consciousness and can be increased through studying, meditation, and experience. Keeping oneself at peace and achieving happiness, and gaining all types of different life experiences is the way to increase Spiritual Energy."

Unlike Physical Energy, which was straightforward, Spiritual Energy was much more elusive. There was no one way to increase Spiritual Energy as shinobi didn't have a concrete way to increase Spiritual Energy reliably. The current chakra theory stated that emotion, life experience, and mental health were related to Spiritual Energy, but there was no consensus on how to harness those components to increase Spiritual Energy.

Spiritual Energies generally increased in a person as they grew up, and they continued to grow until old age when the body would start to deteriorate. There was no peak maturity age or peak period, as every person was unique.

However, Spiritual Energy was fickle.

Like Physical Energy, it was also affected by disease. Impaired mental health, negative stress, unhappiness, and dissatisfaction in life caused a decrease in mental energy. One day, a person could be at 100 points of Spiritual Energy, but the next day, that same person could go down to 80 points because of an adverse incident in their lives.

But simultaneously, negative emotions were good for Spiritual Energy. A person who had overcome depression would see an increase in Spiritual Energy as that was considered another life experience. A person grieving the loss of a loved one could be bad in the short term, but it could have positive effects later on.

Was indulgence good or bad? On the one hand, it made a person happy, which was good for the mental state, but on the other hand, indulgence without limit eroded a person's fortitude against harder times.

Did Spiritual Energy grow more when a person lived a happy life of no difficulties or when they had to face challenges and hardships one after another, leading to a generally unhappy life?

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No one concretely knew how Spiritual Energies worked.

Anko slapped Takuma on his back, which almost made him stumble and fall. Almost. He cursed as he wanted to fall so he could rest, but it was already too late to take advantage of Anko's slap for it and fall down.

"Alright, you can stop running now."

Takuma let himself fall down without hesitation and kissed the ground. He didn't care what Anko thought about him and sprawled out without any shame.

Anko sat cross-legged beside him.

"Do you know that most people have higher levels of Spiritual Energy than Physical Energy?" she said. "In an ideal situation, people would have an equal amount of Physical and Spiritual Energy—but that rarely happens."

"… If the energies are in different amounts… which means chakra volume would be limited by the energy with the lower amount," Takuma muttered as he turned his face towards Anko.

"That's right. And do you know that the difference in amount affects the quality of chakra?" she said.

"Quality of chakra? Chakra has quality?" he said. This was the first time Takuma had heard about it—from his knowledge, chakra was all about quantity.

"Of course. You are aware that every jutsu requires a certain amount of chakra to perform it. If that amount isn't used, the jutsu will fail or won't perform as required," she said. "Most people, however, put in more chakra than needed when using a jutsu— the extra amounts go to waste as chakra can't be stored in the body. Shinobi train the jutsu by performing it repeatedly until they have got the right amount perfected.

"But do you know that people can reduce that required amount. It can be done by going beyond the mastery of the jutsu and understanding its intricacies—but it can also be done by producing higher quality chakra that possesses more 'power per unit' so a lower amount can be used for the same effect."

Takuma didn't know that. He had read some books and papers on chakra theory in his time at the Hidden Leaf, but this wasn't a topic he had covered yet. But then Anko said something that shocked Takuma,

"You have a pretty severe imbalance between the Physical and Spiritual Energy," she said. "A severe imbalance means a lower quality of chakra."

"What? How do you know that?" Takuma asked, skeptical.

"It's in your eyes," she pointed. "People with energy imbalance develop flecks in their iris. Your eyes are dark, so it's not noticeable, but if you look closely, you will see that you have a rather high number of flecks in the inner region of the iris.

"Short, spotty flecks on the outer area of the iris means your Spiritual Energy is lagging behind your Physical Energy. Longer flecks on the inner area of the iris means your Physical Energy is lacking behind your Spiritual Energy," said Anko.

Takuma sat up on the ground, the heavy vest weighing him down. "I don't have enough Physical Energy? But how could that be? I train every day without fail. Conditioning and taijutsu take up the largest measure of time in my training!"

His combat style revolved around getting close to the enemy and using augmented strikes to create openings. To be proficient in his style, he needed endurance and stamina along with agility and dexterity to always be on his feet so as to not get hit while in close-quarters. He trained his body more than he practiced his ninjutsu and genjutsu.

"Well… you're either not training your body… or you have an abnormally high amount of Spiritual Energy in your body," said Anko.

"An abnormal amount of Spiritual Energy?" Takuma muttered.

Could that be it?

'Getting transmigrated into another world is one hell of a life experience. Did that cause me to have the abnormal volume of Spiritual Energy?'

"I don't think training is the problem," said Takuma. "A sensory-nin told me that I am on a Grade-2 chakra scale," which was significantly high for someone Takuma's age, "and if my Physical Energy is lacking, then it must mean that my Spiritual Energy is abnormally high; otherwise, I wouldn't have been able to reach Grade-2."

"Oh, you had your chakra measured by a sensory-nin? Were you worried about your chakra reserves?" she asked.

"No, I hired a sensory-nin to my team," said Takuma.

He was never concerned with his chakra reserves as he hadn't run out of chakra ever in a fight. He only ever paid attention to his chakra control and efficiency with jutsu. But now, Anko was telling him that he had an energy imbalance that was affecting the quality of chakra—he could no longer ignore it.

"I told you that I would be helping you with your chakra control, but I would advise that you take the energy imbalance seriously," said Anko. "I can help you with this, but I wanted to see if it would be a waste of my time—which is why I told you to run with that on." She pointed at the vest. "If you had complained too much, I would've stuck with chakra control training, but you didn't complain once.

She asked, "Do you want to train on the energy imbalance?"

Takuma's answer was obvious. "Yes, I would," he said immediately.

"Good choice," Anko nodded, pleased. "But before we seal the deal. I must warn you of something. Are you aware of the genetic limit?"

"I'm not sure I am," said Takuma.

"As you said yourself, Physical Energy is derived from the cells in your body. But there is a limit to how much energy your cells can hold; once that limit is reached, you won't be able to increase your Physical Energy no matter how much you train. You can continue to grow stronger and faster, but once you hit the limit defined by your genetics, your Physical Energy itself won't grow."

Takuma stared at Anko for a moment as questions popped up in his mind.

"… Does that mean it's possible that if I hit this genetic limit before I'm able to close the gap between my energies, I will be stuck with the imbalance?" he asked.

Anko nodded. "You're still young, and your body is still growing, so I don't believe you will hit that limit anytime soon, but if you continue to train your body diligently, you will hit that genetic limit one day."

"Is there a genetic limit on Spiritual Energy?"

"No, there isn't," she said.

"So, let's say I close the gap one day and then reach my genetic limit. But my Spiritual Energy, which is already abnormally high, will continue to grow, and someday I will again have an imbalance?"

"That is possible," she said.

Takuma sighed heavily. That sounded so bothersome. That even after all the hard work, he could once again find himself in the same place.

"Now, now, don't feel bad. It's an unfairness that all of us face," Anko patted his shoulder. "A good part about having excessive Spiritual Energy is that if you work hard on your Physical Energy, your chakra reserves will grow quickly. And unlike Spiritual Energy, increasing Physical Energy is so much more straightforward. So, cheer up now. You won't get a chance to be happy while we train."

"Eh?"

Takuma felt a shiver go down his spine as he gazed at Anko's playful smile.