I am a high schooler from Michigan in the United States. I wrote an essay on the basics of kinesiology. I would love for you all to read it. Here is the link. Introduction to Kinesiology Do what you love and you won’t work a day in your life. I love the study of the human body, so I have made it my goal to inform other prospective students of kinesiology about the basics. Kinesiology is the study of the movement of the human body. The field of kinesiology has grown in recent years. For years, the field was limited to only physical education teachers. The field of kinesiology now includes but is not limited to coaching, sports marketing, sport promotion, athletic training, sports medicine, sports psychology, sports law, personal training, exercise rehabilitation, conditioning coaching for athletes, fitness managing, gym/spa ownership, exercise specialization for the elderly, corporate fitness specialization, physical education, high-level sports instruction, gym exercise instruction, or specialized instruction for those with disabilities (American Kinesiology Association). In most if not all of these careers relating to kinesiology, the knowledge of the inner workings of the human body is required. Looking specifically at the career of personal trainer, their main responsibility is to help their client’s progress towards their fitness goals. They work one-on-one with clients and are employed by commercial fitness centers. Some personal trainers are self employed. A self employed personal trainer makes more money than personal trainers that work at gyms, but have less regular hours. They are similar to teachers and need to be able to motivate their clients. Personal trainers must sufficiently know exercise physiology, anatomy, and diagnostic methods to be able to accurately determine their client’s fitness levels. They also must have a passion for the subject of exercise and helping others. Also, personal trainers should be good role models by maintaining good physical health (American Kinesiology Association). Most everyone has had a physical education teacher at one time or another. Most of them work in public or private schools. There is a variety of ages to teach in this career, anywhere from preschoolers to college students. A P.E. Teacher’s primary responsibility includes curriculum development, lesson planning, and instruction. The love and enjoyment of being around children is a requirement for anyone considering this career (American Kinesiology Association). Physical education class is not enjoyable when you have a physical education teacher that doesn’t like their students. Unless you’re an athlete, you probably have never met an athletic trainer. They are focused on the prevention, diagnosis, and intervention of emergency, acute, and chronic medical conditions. They are qualified to provide health care from the moment of an injury all the way through when the athlete returns to play. Despite the title, athletic trainers don’t just work with athletes, they work with anyone with an injury. Athletic trainers need to know more than just how to remedy injuries; they must also master the knowledge of anatomy, physiology, and applied biomechanics to put each situation in a broad perspective (American Kinesiology Association). Physical therapists are different than athletic trainers. They work with patients to maintain, restore, or improve the function of various body parts, alleviate pain, and prevent dysfunction. They diagnose and treat musculoskeletal and neurological disorders affecting movement. Their job is to assess the movement capabilities, design rehabilitation regimens, and communicate with physicians on patient’s progress (American Kinesiology Association). With all of these careers, there is a need for the basic knowledge of the inner workings of the human body. Most colleges require at least one course of kinesiology at some point during a student’s academic career. How muscles, bones, tendons, ligaments, the heart, the lungs, and injuries work is a central idea in most of these careers in one form or another. Connecting these two ideas is crucial because anyone interested in a career relating to kinesiology needs to know both about what the careers entail and what some of the basics of the human body are as well. People would not be able to move their muscles without the help of adenosine triphosphate, commonly referred to as ATP, which is the energy source for our muscles. Our muscles are able to move because of cellular respiration. Muscles do two things: contracting to make them shorter and relaxing to their regular length. Humans have 3 different kinds of muscles in your body: cardiac muscle, smooth muscle, and skeletal muscle. Cardiac muscles are obviously the muscles in your heart, smooth muscles carry out the involuntary movements like moving food down your digestive tract, and the skeletal muscles are your biceps and quadriceps and such. Think of muscles as ropes made up of smaller ropes made up of threads. Muscle fascicles are made up of muscle fibers which are the muscle cells. This is the big rope made out of smaller ropes. Muscle fibers are made of myofibrils (myo is greek for muscle). This is the smaller rope. Myofibrils are divided into segments called sarcomeres. Sarcomeres are the threads. Sarcomeres do the actual act of expanding and contracting. Muscles expand and contract in a reaction between two protein strands in the body: actin and myosin. This all happens in a myofilament. The sliding filament model is what it is named when all of the sarcomeres expand and contract together. ("Big Guns: The Muscular System." ). It all connects somewhere. Muscles have to connect to the bone somehow or they wouldn’t be much use to us. If we could look at our muscles, they would thicken in the middle (called the muscle belly) and taper at the ends into a tendon. Tendons are made of fibrous proteins, mainly collagen, and connect the muscle to the bone. Ligaments are usually associated with tendons, but are slightly different. Instead of connecting a muscle to a bone, ligaments connects bones to other bones. ("Big Guns: The Muscular System.") The bare bones truth about bones is that they are actually living! Although bones are a symbol of death because they are what is left over when we are no longer here, they are very much a living thing. Most of your bones aren’t even minerals! Even the part that is, is living tissue because it is honeycombed with blood vessels. Your bone matrix is made up of two parts. The hard, dense outside called the compact/cortical bone, makes up 80% of the bone’s mass. The softer, more porous spongy/trabecular bone is the bone marrow. Bone marrow makes almost all of your blood through a process called hematopoiesis. Two thirds of your bone matrix is made up of proteins like collagen, and the other third is made up of calcium phosphate. A full grown adult has 206 bones. When babies are born, they have about 350 bones. As children grow, their bones fuse together. Exercise puts stress on the bones that stimulates bone remodeling, so your aren’t just building muscle, you’re also building bone. ("The Skeletal System: It's ALIVE!") Our heart and our lungs are some of the most important organs in our body. They work hand in hand to get oxygen to where it needs to go and carbon dioxide out of the body. Lungs have a large surface area so they can absorb large amounts of oxygen at once. We have 807 square feet of oxygen dissolving membranes in our lungs. We breathe oxygen in through our nose and mouth and the air passes down the tube in our throat called the larynx. The larynx then splits off from the esophagus to form the trachea which then splits off into two bronchus, one of which goes into each lung. These bronchus branch off into smaller and smaller tubes called bronchioles. The bronchioles eventually end in tiny sacs called alveoli. We have about 300 million alveoli in our lungs. They are attached to tiny blood vessels called capillaries. Oxygen is dissolved through the mucus coated membrane of the alveoli and is absorbed by the blood in the capillaries which transports the oxygen all over your body. At the same time, the capillaries switch off the carbon dioxide so that it can be exhaled. To inhale, the thoracic diaphragm contracts, allowing the lungs to open up. As the volume of the lungs grow larger from the inhalation, the pressure goes down, causing the air to rush in. To exhale, the diaphragm relaxes, so that the pressure is higher than it is outside, causing the air to rush out. The heart works in a similar pump-like system. In the heart, blood flows from areas of high pressure to areas of low pressure. The right atrium has the lowest pressure of any part of the circulatory system. The reason the heart seems a little bit left of the center is that the left ventricle is so large and muscular. The heart’s job is to power the circulatory system and get the blood back to the capillaries in the lungs so that it can collect more oxygen and dispose of carbon dioxide ("Circulatory & Respiratory Systems."). The respiratory and circulatory systems work hand in hand to allow us to do the things that we enjoy most. Everyone always hears about the childhood obesity epidemic, but what about the children on the other extreme of the spectrum? Does any notice the middle and high schoolers who have training schedules comparable to professionals and are being overworked to the extreme? Of the approximately 45 million children and adolescents involved in organized athletics in the United States, 3.5 million of them under the age of 14 are treated for sports-related injuries each year. (Andrews) I am one of 3.5 million. In 7th grade I strained my hip flexor, but it “got better”, so I just ignored it. The pain was on and off, but manageable. In the middle of my freshmen track and field season, I tore it worse than I had before and had to go to physical therapy. It’s a bittersweet story. I learned about a career field that I’m very interested in going into, but will likely not be able to run competitively ever again. Whether you are interested in becoming a personal trainer, a physical education teacher, athletic trainer, physical therapist, or one of the many other career options, an understanding of how the human body allows us to move is a prerequisite. These two ideas mutually benefit each other. In most if not all of the careers in the field of kinesiology, the knowledge of the human body is required. Works Cited American Kinesiology Association. Careers In Sport, Fitness, and Exercise. N.p.: Human Kinetics, 2011. Print. Andrews, James R., and Don Yaeger. Any given Monday: Sports Injuries and How to Prevent Them, for Athletes, Parents, and Coaches : Based on My Life in Sports Medicine. New York: Scribner, 2013. Print. Green, Hank. "Big Guns: The Muscular System." YouTube. YouTube, 27 Aug. 2012. Web. 11 Apr. 2013. <http://www.youtube.com/watch?v=jqy0i1KXUO4>. Green, Hank. "Circulatory & Respiratory Systems." YouTube. YouTube, 30 July 2012. Web. 11 Apr. 2013. <http://www.youtube.com/watch?v=9fxm85Fy4sQ>. Green, Hank. "The Skeletal System: It's ALIVE!" YouTube. YouTube, 20 Aug. 2012. Web. 11 Apr. 2013. <http://www.youtube.com/watch?v=RW46rQKWa-g>.