As you row each day, pay attention over a period of months to the changes in your muscles. Which ones become sore and then lose the soreness? Which muscles tone up and become stronger? Which muscles did you not know you had before, but now use? What physical activities can you do more easily? Which muscles seem to be little affected? Which muscles provide you more power than others? Which muscles are tight, which relaxed? There are many observations you can make. You will find that what you observe changes over time.

The ability of the muscles to adapt is great. Make use of that ability with a daily row.

Technical Note: Exercise physiologists have found that aerobic training increases the number of capillaries in each muscle fiber. Physiology of Sport and Exercise, by Jack H. Wilmore and David L. Costill (1994, Human Kinetics) at page 147. In addition, aerobic training results in more and bigger mitochondria (the cellular structures that help convert food to energy) in skeletal muscles. Id., at 148.In short, you feel better and stronger when you exercise because your body responds and adapts. It actually changes on a cellular and sub-cellular level in a way that prepares your muscles for more exercise the next day.