Not every body is built for every exercise. Your body type can place limitations on your general athleticism and the methods you use to get there. Exercise is physics for the body, and unwieldy proportions can make certain movements more difficult. Just like a tall person has the basketball advantage, a short person has the pushup advantage.
The Body as a Lever
During a pushup, your body is a lever, ExRx says. The place where your feet touch the ground is the fulcrum, your hands provide the force and your center of gravity is somewhere in the middle. All other factors being equal, it should be easier for a taller person to do a pushup because the force is further away from the fulcrum, providing more leverage. Think about loosening a bolt with a wrench: The longer the wrench, the easier it turns. But when it comes to bodies, there is more at play than just leverage.
Center of Gravity
The closer the center of gravity is to the source of the force, the more difficult the movement because less weight is being supported by the fulcrum. Taller people generally have longer legs than shorter people, which means that their center of gravity is closer to their hands, making the pushup more difficult. Differences in body type matter, too. If two people are the same height, the one with more weight around the hips and thighs has an easier time doing pushups than the one with more weight in the abdomen.
The further the force must move the weight, the more difficult the movement. Taller people have longer arms than shorter people, so their body must travel a farther distance from the floor on every repetition, according to the U.S. Department of Energy. If two people of the same weight but different heights do pushups, the shorter one has it easier because of the shorter distance to the floor.
Muscular strength is also a factor. The stronger the muscles, the more force the person can apply to push his body from the floor. If two people of different heights are equally proportioned, having the same percentage of muscle mass, they should be able to do pushups at an equal rate because the taller person has a higher volume of muscle to compensate for the other disadvantages.