This is a great question. Here are some points that might help you.
First, appearance matters in our society. There is no doubt about this. We can tell that appearance matters by how much money, time and energy are spent on a person's appearance. We see this not only in people, but also companies that advertise. Furthermore, we need to keep in mind that this is not just something that women do, but also men. In light of this, there is a strong connection between strength and appearance in men.
Second, in light of this, often men seek to portray themselves in certain ways through working out and even in the way they dress. Often in the business world, they wear power suits and ties to show that they are strong. Uniforms also show something similar in the military and other fields as well. All of these examples shows that there is the connection between strength and appearance.