How can Boruto handle a Chōōdama Rasengan? We see that at the end of Boruto:Naruto the Movie,


   Boruto defeats the enemy by hitting him with what it seems a Chōōdama Rasengan (IMHO it looks larger than a Chōōdama Rasengan). I think Naruto infused some of his chakra in Boruto's jutsu to make it that big.


We see it took time for Jiraiya and Naruto to master the Rasengan, and Naruto was actually the only one to take it to the next level by adding his wind chakra (at the time).

So how can Boruto handle this large amount of chakra? Yes everyone says that Boruto can easily beat Naruto if you compare them at the same genin stage of their lives, but that doesn't mean Boruto is trained to manipulate such an insane amount of chakra. How was he able to pull it off?
The only strain Rasengan users show is from the chakra required to create it - It requires a LOT of chakra to create. Manipulating the chakra, while difficult to master, doesn't seem very draining. Even genin Naruto was able to spend entire days practicing the chakra manipulation part. Since we've seen Boruto make his own Rasengan, we know he understands the chakra manipulation part, so he can obviously handle using/attacking with it. He doesn't however have the completely bonkers reserve of Chakra that Naruto has, so he can't make the Giant Rasengan himself.

There's no reason to assume that the mechanics of the Rasengan change as it gets larger, so Boruto's own ability to manipulate chakra flow should be similarly applicable across all sizes of Rasengan.

I'd even wager that the manipulation part isn't particularly important, since we see Naruto give his friends Rasengans of their own to use during the Fourth Shinobi War, implying that it may be a completely self-sustaining jutsu so long as there is a chakra supply.