After the training, Yujiro, seeing this as a perfect excuse, went to inquire with his teacher.
"Sensei, since this training takes so much chakra, do you have a way to permanently increase our chakra reserves?"
"Brat, what do you need so much chakra reserves for, you already have more than enough to last the whole training time?"
Hiramasu confused asked.
"If I want to do this kind of training by myself, I need more chakra to do this at home.
So do you have any methods?"
After a while of considering, Hiramasu gave a negative answer.
"Kid, you already have more chakra than Mujin, and he is a member of my Senju clan. We naturally have much more chakra than ordinary ninjas.
As for methods to increase chakra reserves, you can forget about them. The methods I know, either have extremely high requirements, have high risks, or have significant side effects.
Your best method to increase chakra reserves is with training and age."
Hearing Yujiro heard Hiramasu's firm refusal he was surprised.
'I didn't think his refusal was going to be that firm, at worst I thought he would have told me a couple of methods and exaggerated the downsides of the methods, not just straight up refusing to tell me any.
Well no matter, I already know a couple of methods but they are a bit uncertain if I will get the opportunity.
The first one is obviously Hashirama cells, which can be seen from Obito to increase chakra reserves humongously, otherwise it's doubtful that a 14 year old Obito could last in a 1v1 fight against the fourth hokage.
Then there is the tailed beast chakra.
Although it can increase chakra reserves as seen from the seal Minato put on Naruto. I don't know if it has to be a slow progress like how Naruto's eight trigrams seal, slowly allowed the Nine tails chakra to leak into the chakra network, although it eroded the seal, and interfered with Naruto's chakra control, the chakra reserves he got for such minor troubles is enviable.
But I don't have access to either of those right now, the earliest I could get access to Hashirama cells, will be in about 4 years when the Uchiha massacre happens from root, and the earliest I can use tailed beast chakra is when I master a seal like eight trigrams seal, that can leak chakra to the chakra network.
As for where I will get the nine tails chakra, isn't there enough of it in the fire temple?'
After having such thoughts in just a couple of seconds, yujiro showed a dejected expression to Hiramasu.
"Yes sensei."
After seeing Yujiro's dejected look, Hiramasu relented a bit.
"Don't worry, even though the shortcuts to get more chakra we have in Konoha are limited to methods with huge risks or side effects, we have many methods to stably increase chakra reserves with training."
After hearing this although Yujiro knew he could get stronger through this method, he was a bit annoyed as this meant that he would need to continuously train for more than a decade to ensure his own safety in the 4 great ninja war in the least, and that's not even talking about surpassing the level of ordinary ninjas and accenting to the levels of Hashirama and Madara.
After such interlude passed on the next morning when the three woke up, they all noticed something different.
None of them had any soreness.
When they reached the training ground 32, they all gathered around Hiramasu to ask questions.
Hyori, the most impatient one, acted first.
"Sensei, how come I don't feel any soreness? Is this the effect of the chakra reinforcement method you taught us? What are the other benefits of this?"
Hyori bombarded their sensei questions that he had no time to answer.
After a moment of calming Hyori down.
Hiramasu started to explain the questions that Hyori bombarded him with.
"There are several benefits to this method, the first and foremost, is the recovery boost this method provides.
This recovery happens, due to the cell activation that the yang chakra you reinforce your body with.
Due to the high chakra cost this method costs, it will rapidly increase your chakra reserves and control.
The control comes due to the fact that you will instinctively start to control the chakra more effectively over time.
While the increase in chakra reserves is due to your chakra reserves hitting rock bottom and recovering resulting in the increase of your chakra reserves, and the other methods they increase faster than normally is related to the first benefit of this technique, your chakra will increase due to the fact that you can train with more intensity, resulting in higher physical energy."
After explaining the benefits, Yujiro asked a question.
"Are there any downsides, like faster aging due to the fact that increased recovery means faster cell division?"
"While that's normally the case in medical ninjutsu, using yang chakra to increase cell division, this method doesn't increase cell division, instead it increases the activity of your cells.
And unlike you think this method probably has a positive effect on your lifespan, as you can see the members of the Senju clan have a long lifespans."
After a moment more of discussion about the matter Hiramasu put them to training.
"You can ask more questions later, you better start your training, otherwise I will extend the time of your training by double the time you delay."
After Hiramasu made such a threat, the three kids immediately started the training regiment.
Although the training should have been more easy for the chakra reinforcement, the training felt much harder to the three kids due to their sensei, forcing them to increase the restriction that their training seals provided.
And like Hiramasu had predicted, Hyori ran out of chakra halfway through the session, while Mujin ran out of chakra 50 minutes before noon while Yujiro ran out of chakra 30 minutes before noon.
While Hyori was forced to put down the activity of her training seal due to the training time ahead, Yujiro and Mujin were granted no such luxury, they were forced to keep up their training seals at the previous level, and Yujiro was even forced to increase the activity of his seal.
As a result, the three kids were at an almost same state after the morning training.
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