Chakra Refinement and Testing

In the basement, Hyuuga Nen held a book on chakra refinement, reading it with great focus.

"Chakra is formed by combining physical energy and spiritual energy. Physical energy comes from the 130 trillion cells in the human body, but the book's description of spiritual energy is rather vague." Hyuuga Nen frowned and set the book down.

After a while, Hyuuga Nen stopped dwelling on the problem. He sat upright, took a deep breath to relax, and pressed his palms together. Following the methods in the book, he attempted to sense his own spiritual energy and combine it with his physical energy to extract chakra.

Half an hour later, Hyuuga Nen silently lowered his hands. "It's not working. I couldn't sense my spiritual or physical energy. Oh well, there's no use rushing it."

Hyuuga Nen calmed his mind, telling himself not to be impatient, and picked up a book on taijutsu training instead.

An hour later, Hyuuga Nen put the book away and stood up, ready to find a place to practice his physical techniques. Tucking the book into his tunic, he walked out the door and headed toward the forest.

Upon reaching the forest, Hyuuga Nen began by practicing punches and kicks according to the techniques recorded in the book. Once finished, he moved on to supplementary training for strength, endurance, and flexibility, performing squats, push-ups, long-distance running, and stretches.

By the time he finished all his training, it was already noon. Hyuuga Nen was panting, drenched in sweat, and his legs felt like jelly.

"My body isn't used to this; it's my first time training," he muttered, slowly making his way back home.

This training continued for three days. Hyuuga Nen gradually adapted to the exercise and finally managed to extract a wisp of chakra.

That morning, Hyuuga Nen sat on the basement floor, closed his eyes, and sensed carefully. Confirming he hadn't made a mistake, he slowly raised his hands. Looking at his palms, a smile tugged at the corners of his mouth.

"Finally, I've extracted chakra. This feeling is wonderful!" Hyuuga Nen calmed his emotions and began to ponder.

"Judging by these past few days of training, my aptitude should be decent. I have plenty of energy; although I was prone to sleeping before I turned six, that's no longer the case. I recover immediately after resting from high-intensity training. Extracting chakra in three days is already quite fast."

At this moment, Hyuuga Nen recalled his previous tendency to sleep excessively. "What caused that? Was it the transmigration? Or something else? I have no way to find the reason now, but I hope it won't have any negative effects on me." Hyuuga Nen suppressed his worries and thought silently to himself.

Hyuuga Nen was quite satisfied with his performance over the last few days. In the days that followed, he spent his mornings refining chakra and practicing taijutsu, and his afternoons studying the theoretical ninja textbooks his father had given him.

Through these materials, Hyuuga Nen learned many methods, precautions, and taboos for ninjas on missions.

At night, it was time for Hyuuga Nen to put his knowledge into practice. This period was primarily dedicated to tracking and anti-tracking training, with Taro serving as his training partner.

During tracking drills, either Hyuuga Nen would track Taro, or Taro would track Hyuuga Nen.

At the start of the training, Hyuuga Nen suffered a major blow. He found it very difficult to locate Taro, and even when he managed to track him, he couldn't catch him—after all, Taro was stronger than he was.

Taro, relying on his keen sense of smell, could easily find Hyuuga Nen. This led Hyuuga Nen to doubt whether he had any talent for being a ninja at all.

Hyuuga Nen adjusted his mindset and applied the methods from the books, such as wading through water or rubbing strange substances on his body, while combining them with the Three Body Technique he had recently learned to confuse Taro.

When tracking Taro, besides using the knowledge from the books, he also learned from Taro himself, utilizing factors like fur, footprints, and scent to track him. Finally, his "track record" began to look a little better.

Occasionally, Hyuuga Nen would even track wild animals in the forest with Taro. Through this period of training, his tracking and anti-tracking abilities improved significantly, and he was no longer a complete novice.

In the evening, Hyuuga Nen finished his "game of hide-and-seek" with Taro and returned home. Seeing him arrive, Rika looked at him with a slightly complicated expression and said, "Nen, I've already told people about your desire to become a samurai."

Hyuuga Nen nodded after hearing this, lost in his own thoughts, and failed to notice Rika's expression.

"It's been three months since I first extracted chakra. I haven't slacked off on my refinement during this time, and aside from the Three Body Technique, I haven't learned any new ninjutsu. Now, the amount of chakra I've accumulated is enough for that experiment. I'll start tomorrow."

The next day, after waking up, Hyuuga Nen skipped his chakra refinement and went straight into taijutsu training. For the entire day, he only performed basic physical exercises and read books; even his evening training was suspended to minimize chakra depletion.

Hyuuga Nen's goal was to test how long chakra could be stored in the human body after extraction and its natural rate of dissipation. After all, he was in a real world now, and his previous understanding of chakra was only superficial; only by understanding it clearly could he better master it.

This experiment lasted for half a month, and Hyuuga Nen reached a preliminary conclusion:

"After chakra is extracted, it can be stored in the body, but it gradually dissipates as it flows through the meridians. If it isn't replenished, it will completely vanish in about half a month. As for the rate of dissipation..."

"I can only say it's neither fast nor slow," Hyuuga Nen added softly. "Thankfully, a ninja's body isn't a sieve. If it were, that would be terrible."

"As for whether someone with chakra recovers automatically once it's depleted, perhaps not, or perhaps they do—the amount might be too small for me to sense. If the opportunity arises, I'll explore that later. For now, I should prioritize increasing my strength. My training plan needs to be revised."

In the following days, Hyuuga Nen modified his training schedule. During the day, he studied theoretical knowledge from books and practiced sessions that didn't require much space directly in the basement.

For training that required more room, Hyuuga Nen would sneak into the forest late at night, such as for shurikenjutsu or ninjutsu practice. During these sessions, he would have Taro stand guard to avoid being discovered by others.

Hyuuga Nen also added combat training to his curriculum. Because his resources were limited, he could only spar with Taro for now. Day after day, through study and training, Hyuuga Nen felt himself growing stronger bit by bit.