In the hit manga series, Dragon Ball, Goku and Vegeta are constantly training. While the story is largely fantasy, there is actually some scientific basis to it. The training the Goku and Vegeta undergo may not be entirely possible, but the underlying principles are legitimate.
Goku and Vegeta are Super Saiyans who routinely fight threats to Earth and participate in fighting tournaments. As a result, they are constantly seeking to grow stronger. They spend a great deal of time in the series
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