Strength is the ability of the muscles to perform work at a high intensity consistently and it is build, over time, by making muscle groups work under load on the entire muscle fiber. This is a workout that is performed deliberately and with focus. Attention is paid to technique so that form is maintained. You won't get out of breath but you will work up a sweat.
Extra Credit: Do 30-count plank at every set.
https://www.youtube.com/watch?v=sp5cOai5klU
