Unless your character is made to be ironic, then try to stick to this:

Their body build will depend on their fighting style, genetics, and eating habits.

|| GENETICS OR BODY TYPE ||

SO LIKE BY GENETICS I MEAN THEIR NATURAL BODY TYPE BC EVERYONE HAS DIFFERENT BODY TYPES AND I DONT KNOW WHY IM FUCKING YELLING BUT MY CAPS HAS BEEN ON AND I DIDNT TURN IT OFF FOR THE FIRST TWO WORDS AND I DIDNT WANT TO DELETE AND RE TYPE AND OK LEMME stop.

Generally, (and quite arbitrarily) these are the body types we have for both male and female.

In more detail, when describing your characters shape, there is the general description and the specifics.

For example, you can say that Sakura has a quite boxy shape (not really but eh) as a general description. However, specifics would be something like her muscular thighs and arms or her wide hips or her small chest.

Describing your character's body shape can make them seem more real and give the reader an image of your character. Also it's good to know for like character charts or whatever.

|| EATING HABITS ||

Generally, the amount of food someone eats goes in relation with their body mass.

For example characters like the Raikage probably eat more than characters like Sai. Because they have their incredible muscles to feed.

|| FIGHTING STYLE ||

Ok so, I'll do a more in depth discussion about naruto and their fighting styles and all. This is just a general overview of how fighting style and body build relate.

The thing is, their body build either affects their fighting style or their fighting style affects their body build.

Take characters like Sakura, The Raikage(A), Killer Bee, and Karui. They are muscular because their fighting styles are all about POWER and STRENGTH.

Characters like Hinata and Neji have more soft fighting styles, so although they have muscles, their body build is not as muscular as hard hitters.

Characters like Chouji have bigger body build, so he uses his body to attack. Meaning his body build affects his fighting style.

Notice how characters like Lee and Gai have lean yet muscular builds. This is because unlike characters like the Raikage, they need to be light on their feet

END

PS. ANYTHING ELSE YOU THINK I MISSED? PUT IT IN THE COMPLAINT BOX

oh wait, there is no complaint box.

Oh well.

(trying to get this looks section over with so we can get to the FUN stuff)