This is an excerpt from Smarter Workouts by Pete McCall.
Exercise is much more than working up a sweat; when done properly it can change the function and structure of the human body. Mobility training can improve movement efficiency and strengthen the fascia and elastic connective tissues, helping them to be more resistant to injury. In addition to enhancing aesthetic appearance, strength training and metabolic conditioning can be used to improve the ability to convert food to energy, change hormone levels, and increase muscle force output, all of which are critical for performing your favorite pastimes or essential activities of daily living. Using exercise to achieve these and other desired results relies on a number of different variables, including sex, age, resistance-training experience, genetics, sleep, nutrition, hydration, and emotional and physical stressors. Each of these influences how your physiological systems adapt to exercise in general or resistance training specifically; for example, too much stress at work or a lack of sleep may significantly reduce your ability to grow muscle.
An exercise is a movement, and movement is a skill that requires practice to master. It may be tempting to change exercises frequently; however, maintaining some consistency with the same exercises over a period of six to eight weeks can help improve coordination and movement skill as well as muscular strength. Efficient movement patterns require synergistic coordination between all systems of the human body. Exercise programs that emphasize using movement patterns use a number of muscles at the same time, which can make the workouts more metabolically challenging, helping you burn more calories, which is essential for maintaining a healthy body weight.
To create and sustain the energy for dynamic, multidirectional movement patterns, the different components of the body need to develop the ability to function as a single system controlled by the CNS. Compared to the limitations of traditional muscle isolation exercises, using only one piece of equipment to challenge the body to move in all directions can result in a more creative, engaging, effective, and fun workout experience. Multijoint movements such as squats to shoulder presses with dumbbells, lifts with a medicine ball, or kettlebell swings are all examples of exercises that involve large amounts of muscle tissue and, in turn, challenge the heart to pump blood to keep the muscles fueled, which can provide a number of health-promoting benefits.