Chapter 5: Chakra and Rock Lee

After dinner, Kazuki Haruno returned to his room and took out a book related to chakra extraction. To be honest, he had never studied this hard, even in his previous life.

Kazuki had a basic understanding of chakra, but he didn't know how to extract it. He had thought about asking Siné for help, but unfortunately, she mentioned that although she could still use chakra, she had already returned most of the related knowledge to her former instructors. Besides, Siné didn't recommend extracting chakra before the age of six, as it could have an impact on the body.

Kazuki had been contemplating the concept of chakra. Chakra is a combination of physical and mental energy, and extracting it would inevitably affect the body.

Mental energy determines the amount of chakra one can extract at once, while physical energy determines the total reserve of chakra. Only when physical energy is combined with mental energy can it become usable chakra.

Kazuki also noted that physical energy is influenced by both one's physical fitness and bloodline. Physical fitness can be improved through training, but bloodlines are mostly fixed. For ordinary people, the bloodline coefficient is low, meaning they need excellent physical fitness to have a sufficient chakra reserve. However, certain bloodlines, like the Uzumaki, have an incredibly high coefficient, allowing them to have enormous chakra reserves without requiring extraordinary physical fitness.

Bloodlines also influence recovery speed, but that isn't as significant. Most battles are decided in a few moves, so faster recovery doesn't play a big role in one-time fights.

Kazuki had wondered if there were any treasures in this world that could enhance bloodlines, but none came to mind. The Hashirama Cells? Kazuki wasn't keen on turning into a half-human, half-monster. Instead of transplanting Hashirama Cells, it might be better to plan for capturing a tailed beast, though neither of these options aligned with his goals.

Kazuki wanted to grow to the pinnacle of power as a human, even if other forms could be stronger. He wasn't interested in becoming a Jinchuriki or using artificial enhancements that would turn him into a monster.

After all, if he ended up looking like a monster, he might as well just follow behind the two main protagonists of the series, maintaining enough strength to avoid being sacrificed as cannon fodder.

Kazuki was quite laid-back in his approach. If he could become stronger, that would be great. If not... well, so be it.

After thinking it through, it seemed like there truly weren't any treasures in this world that could improve bloodlines. Perhaps there was the Dragon Vein, but Kazuki couldn't recall exactly when it would appear, and it didn't seem to fit his goals anyway.

With a sigh, Kazuki thought how much better things would be in a world of cultivation. There would always be strange items that could enhance even basic attributes. Although such things were rare, at least there was hope, unlike the Naruto world where most growth relied on natural "mutation."

If such a treasure were given to him now, he probably wouldn't be able to resist using it. Rationally, it was more practical to grow stronger, even if emotionally he didn't want to.

But for now, while he was still weak, he couldn't afford to be picky.

Once Kazuki had grown stronger, he would probably turn down those enhancements. The question was whether he could truly grow to that point or not.

After reading for a while and feeling like his food had digested, Kazuki closed the book.

"Mom, I'm heading out."

"Come back early and stay safe."

Siné was already used to Kazuki going out every day. She had thought today, being the first day of school, would be an exception, but he still insisted on going out.

Playing was not on the agenda. Since chakra was fundamentally based on physical energy, Kazuki had decided to avoid being lazy. He wanted to ensure that he wouldn't face chakra depletion after using just a few jutsu in the future.

Although he had been training consistently, his current physical fitness was probably equivalent to that of an average second-year student.

However, recently he had noticed an improvement in his physical condition. Even though the intensity of his training hadn't changed, it seemed like his body was adapting, likely due to his growing age. This made Kazuki think he could increase the intensity of his training.

That said, he still needed to test his limits. While it was okay to push his potential, he had to avoid overexerting himself. After all, his body was still only six years old, and while strength was important, it was equally vital to ensure he had enough energy for growth. He couldn't afford to sacrifice long-term development for short-term gains.

Still, a few times wouldn't hurt, so Kazuki decided to experiment with pushing his limits today. Maybe even break through them once, just to see.

In fact, breaking through wasn't too difficult for Kazuki. He had done it once before, probably due to the strength of his soul, but afterward, his body had felt empty for days. That was a clear sign of overexertion, and since then, he had avoided training to such extremes.

But today, Kazuki felt ready to try again. He quietly made his way to a secluded training ground. Sure enough, someone was already there.

Kazuki was familiar with this person—Rock Lee. No matter when Kazuki arrived, Lee was always training. Even after Kazuki finished, Lee would still be going strong.

Lee was what you'd call a hard-working genius. Kazuki respected him, but he couldn't help but feel that Lee's training methods were overkill. While Kazuki's theoretical limit was likely higher, it was based on the assumption of an unlimited growth period. In reality, human growth was limited, and Kazuki wasn't sure he'd reach his full potential before his body stopped growing.

So while theory was one thing, reality was another. For now, Kazuki didn't see himself surpassing Lee in terms of physical prowess, and honestly, he didn't care to. After all, he had seen firsthand just how hard Lee worked.

"Oh, Kazuki! You're half an hour late today. You'll need to do extra sets!" Lee's eyes lit up when he saw Kazuki. Though he was used to training alone, having a partner always made him happier.

"Sure," Kazuki replied, deciding to push his limits today. A few extra sets might not be enough for him.

Lee was surprised by Kazuki's response. Usually, Kazuki would refuse extra sets, but this time he agreed right away. Lee's eyes burned with determination.

"Ohhh! Kazuki, you've agreed! This is youth! I'm fired up now! I'll reward myself with a few extra sets too!"

Kazuki felt a bit awkward. No matter how many times he had seen it, Lee's enthusiasm always seemed a bit exaggerated.

With that, their training session began. Though they were in the same space, their training methods differed. Kazuki believed his body was still developing, so he refrained from overly intense exercises, focusing instead on low-intensity training and gradually building up his stamina.

Time passed, and even though the intensity wasn't high, Kazuki was already out of breath. But he hadn't yet reached his goal for the day. His body was nearing its current limit, but his mind was still holding up, allowing him to keep going.

Lee, watching from the side, felt moved to tears. This was what it meant to ignite the flames of youth!

Suddenly, Kazuki's movements became smoother. Lee was all too familiar with this—it was a sign of breaking through!

This time, Lee truly shed tears of joy.

"Phew, finally made it." Kazuki realized his limit was higher than he had expected. Well, it wasn't exactly his true limit, just the maximum his body could currently handle.

After a bit more training, Kazuki waved goodbye to Lee and left, walking away with heavy steps. His body was exhausted, but his mind was still sharp. He figured he'd go home and study some more, hoping to learn chakra extraction soon.

The next day, Kazuki was surprised to find that his body felt fine. Had his physical progress been that significant? He decided to push his limits again.

By the third day, however, Kazuki was done. His body felt fatigued all the time, so he had to resort to basic exercises. It seemed that while breaking through was possible, he couldn't do it continuously. Finding the right interval between these breakthroughs was key.

Kazuki sighed. Physical training, chakra accumulation—it was a long road ahead.

(End of Chapter)