Now, I am just giving my best guess, but I think I was able to connect the dots on why. So, here we go.
Firstly, the picture below is just one of many examples of gags Akira Toriyama placed into his manga series, Dragon Ball.
The next photo shows Akira hanging out with martial artist and actor, Jackie Chan (1954- present), who is also known for his COMIC TIMING in film.
So, Akira is clearly a fan of Jackie Chan, which means he likes Jackie's comedy. If one watches Jackie's movies, he or she will see his comedy in Akira's work. But were does Jackie's comedic influence come from? I think it might derive from the performance of American actor, comedian, and stunt performer Harold Floyd (1893-1971). Now, why do I say that?
Below is a still of Jackie hanging from a clock tower in his 1983 film "Project A." And below that is a still of Harold Floyd doing the same thing in the 1923 silent romantic comedy film "Safety Last." So not only is Jackie's type comedy infused in Akira's work but also that of Harold Floyd.
Just food for thought.