Another theme could be his self - confidence boost. When Naruto is fit, he often feels more confident in himself, which is reflected in his interactions with others. He may be more assertive in making decisions and leading his team. In some fanfictions, his fitness also plays a role in his relationships, like impressing Sakura or showing off to Sasuke.
A common theme is Naruto's enhanced combat abilities due to his fitness. He can execute his moves more precisely and powerfully.
A common theme is growth. Little Mac can grow in his physical abilities with the help of Wii Fit Trainer. Another theme is friendship. They often form an unlikely friendship in the stories.
One common theme could be illness. The coughing fit might be a symptom of a more serious disease that the character is dealing with.
One common theme is character relationships. For example, exploring the deepening friendship between Naruto and Sasuke, or Naruto's romantic relationships with characters like Hinata. Another theme is the expansion of the ninja world. Writers might create new villages, new ninja clans, or new jutsu. Also, the idea of alternate universes is popular, where the events in the original 'Naruto' series take a different turn.
One common theme is alternate universes. Writers often like to create scenarios where Naruto and his friends are in a different world altogether, like a modern - day setting or a fantasy world other than the ninja world. This allows for a fresh take on the characters.
One common theme is the passing of the torch. Older Naruto is often shown mentoring the younger generation, like how Kakashi mentored him. Another theme is dealing with the scars of past battles, both physical and mental.
One common theme is the exploration of their self - discovery. Since they are the same person in a sense, they can see different aspects of themselves. For example, one Naruto might be more confident while the other is more reserved, and they learn from each other.
Teamwork is also a big theme. Despite being the same person in essence, the two Narutos often have to learn to work together. This can be challenging as they may have different personalities due to their different experiences. For example, one Naruto might be more cautious while the other is more impulsive. And the theme of friendship also plays a role, as they are, in a way, their own best friends in these stories.
Another theme is self - discovery. As Naruto faces his dark side, he often learns more about his true nature, his powers, and his place in the ninja world. It's like a journey of self - exploration but with a dark and dangerous twist.
Another theme is perseverance. Changing from an unfit to a fit state, whether it's physical or mental, is not easy. The characters usually face many obstacles. In these novels, they have to keep pushing forward despite difficulties, which shows the theme of perseverance. For example, they might face mockery from others for their initial state or struggle with the hard work required for the transformation.
One common theme is the struggle for power. Naruto has to push himself to the limits to become a brutal fighter, often facing stronger opponents. Another theme is self - discovery. As he becomes more brutal in his fighting, he also discovers new aspects of himself.