One thing to remember is that being shorter, your muscle strands are shorter. I am just over 6-1 and weigh about 220 with a 34 inch waist and I am not fat. That may make me sound like I am a big guy but the muscle is stretched over my 6-1 frame. My muscle strands/fibers are longer than yours due to my height and the length of my arms/legs, and so forth.
What does all this mean? Well, it's easier for you to bulk up than for someone tall like me. Think about it... with shorter muscle strands/fibers, you don't have to move the weight as far as I do. Therefore lifting weights will require less energy output for you than for me. That does NOT mean lifting is easier, it just takes less energy output. This translates to your muscles getting the same workout as me but with less energy output.
Now translate that to your training... what does that mean for you? In theory, your 50th punch should be stronger than the 50th punch of someone with longer muscle strands/fibers than you. Think about that and use that to your advantage. Technically, if you train right, your muscles should be fresher in round 3 than someone who has longer muscle strands/fibers.
Also, when you are inside, your punches will require less energy to have the same force as someone who has longer muscle strands/fibers. You can be devastating inside. Think about that.
But, on the down side, guys, like me, who have longer muscle strands/fibers tend to have bigger d*cks.....
Sorry...couldn't resist that one.