Some will throw in the towel and believe that they have reached their limit. Others will subscribe to the latest diet fad while the rest keep doing the same thing hoping to break through the wall like Kool-Aid Man, "Oh Yeah!" included. What is the deal? What is going on and what should you do? First, take a deep breath.
Now, let's explore!
The human body is AMAZING! Many of us fail to truly appreciate the way our bodies adapt and often we don't even realize that it is. Think about it. If the vertebrae of your neck go out of alignment your body will alter the position of your head to keep it balanced- AMAZING! Normally notice is taken when the pain and/or discomfort sets in which is how our bodies tell us something is wrong. Regardless of the cause, injury or exercise, your body will update and modify whatever necessary to keep you going.
So if you keep doing push ups three days a week eventually your body adapts and you will no longer get the same results unless you change something. It could be the speed of your push up or hand placement, there are many possibilities. Basically your body is at point A, your goal is point C but you are stuck at point B. You have plateaued.
Although at first this may be frustrating keep in mind you have made a difference, congratulations! Now it is time to alter the demands so you can continue ascending toward your goal. Just as every science experiment has a variable and control group the same applies to fitness routines. Let's use running as an example. Someone preparing to run a race will not simply go out and run as much as possible right up to race day. There is mileage that can be shortened or lengthened. Speed or hilly terrain can be altered as well. On top of these variables is the runners' weight training program that prep the primary muscles utilized so they will have the strength to perform well. All of this manipulating a variable and planning is called periodization.
"In training nothing happens by accident, but rather by design."
When you push yourself from point A and get stuck at point B listen to your body and spice things up so you can be on the way to point C. As you reach more goals, accomplishing things you thought were not possible, you will continue to make changes to your routine.