CHAPTER 1 GENERAL INTRODUCTIONIntroduction”Exercise is an optional, movement is an essential”. Exercise is generally focused on specific action and it does not require much real skills. In modern era, the easiest way to exercising is by using machines such as treadmill make human experts in movement rather than practical and it is limited.Movement is a necessities. Human body with help of muscles are designed to move. Point of concern of public health research nowadays is to develop interest in human to move more move in live, and develop human body to exercise to remain healthy.
For an instance, no other of exercise will undo the pathology that is sitting and remaining sedentary. Conversely, human can enjoy their life without doing exercises but the muscles in the body needs to be moved to remain healthy. Physical ActivityPhysical activity such as walking and sitting on the chair means movement of the body that uses energy. For health benefits, physical activity should be moderate or vigorous intensity.
Movement of body should be in stable state in order to prevent from injuries. WalkingWalking can be considered as a good full body exercise. Although bipedal locomotion is a complex interaction between muscles and bones. While legs are moving, the arms still have to swing and the core still has to work to stabilize our body from falling down and minimize from any injuries. Besides, in such a way that enables humans to adapt their gait pattern to various environment and surfaces such as slippery surface effortlessly without thinking.
The primary muscles involved in walking are the muscles of the lower leg such as soleus, gastrocnemius, tibialis anterior and tibialis posterior.Main muscles involved in walking and their function is a must to know in order to understand the gait cycle. Based on expert , in the gait cycle (Figure 1.2), the muscles have four main functions which are:Controlling the upper part of the body’s posture and balance.Generating energy associated with forward and upward propulsion.Controlling the body’s vertical collapse and shock absorption during loading response.Controlling the body’s center of mass and its displacement.Walking gait cycle consists of one step which it begins when one foot initially touches the ground and ends when the same foot touches the ground again repeatedly after completing its two main phases: stance phase and swing phase.968829241663001519555131657Figure 1.2: The gait cycleFigure 1.2: The gait cycleStance PhaseIn normal walking, about 60% of gait cycle represented of stance phase. As it is describes when the foot make contact with the floor. Stance phase can be divided into for sub-phases: loading response, mid-stance, terminal stance, and pre-swing. Table SEQ Table * ARABIC 22.214.171.124: Explanation of stance phase of gait cyclePhase of stance Percentage of gait cycle ExplanationLoading response Approx. 0% to 10% When the foot first touch the ground (initial contact)Also called heel strikeEnds with toe-off by opposite legInternal flexor of the knee is greater, where the anterior position of the force vector.Mid-stance Approx. 10% to 30% The opposite toe off and supporting limb’s heel off.To stabilize and to maintain progression over static foot.While the foot is flat on the ground, ankle rocker occurs and it symbolized by rotation of forward tibia around ankle.Terminal stance Approx. 30% to 50% Starts with heel off and ends with initial contact or heel strike of the opposite foot.The soleus and gastrocnemius triggered, the heel rises and the tibia continually to rotate around the ankle. Muscles connected to knee completes its extension.Pre-swing Approx. 50% to 60% During peak of hyper-extension, hip joint begins to flex.The tibia rolls forward, the thigh moves forward too.Swing phaseSwing phase of gait cycle is determined when one foot is in the ground while the other one is in the air.Table SEQ Table * ARABIC 126.96.36.199: Explanation of swing phase of gait cyclePhase of swing Percentage of gait cycle ExplanationInitial swing Approx. 60% to 73% When the foot leaves the ground, immediately ends with swinging foot adjacent to the stance foot.Contraction of Triceps Surae stops and Tibialis Anterior starts to active Mid-swing Approx. 73% to 87% Tibialis anterior prepares for huge contraction forces.Contraction of hamstrings start eccentrically, power absorption occurs.Terminal swing Approx. 87% to 100% When swinging of tibia is vertical, terminal stance happens, beginning of a new stance phaseHamstrings starts decreasing it contraction, Gluteus Maximus and Adductor Magnus starts to control indicates a need less involvement of knee joint for hip extension.Stand-to-Sit(STS)The easiest explanation of STS is a movement of sitting down to seated position (Figure 1.2.2). Each person typically performed this activity for several times per day. Most of the elderly persons and individuals with disabilities are faced a hard time doing sit-to-stand or vice versa, stand-to-sit. For example, health condition of the aging persons and other reasons such as people of muscle weaknesses, diseases, and disabilities like stroke and Parkinson’s declines functional mobility. There are more than 600 muscles found attached to the skeleton, the main muscles used to carry out sit-to-stand activity is located in human legs and lower torso. The lower leg muscles such as the calf and ankle muscles such as Tibialis Anterior, Soleus and Gastrocnemius. Besides, muscles in the leg are responsible for human to carry out others activities such as lifting objects, flexing, and stretching and straightening out the body as human sit and stand.Sitting down for too long can cause few health issues such as bad back posture and back pain. In order to avoid back pain, sitting in good posture benefits human such as:Strain on the body can be reducedWear and tear on the joints, muscles, and ligaments can be reducedSpine health can be improved85449821399500CHAPTER 2 LITERATURE REVIEW2.1 Body organization All living organisms are made up of one or more cells. Consist of only one cell like amoebas is called unicellular organisms. Consist of more than one cell like human and animal is called multicellular organisms. To summarize, similar group of cells work together on a specific task to form tissues. Organs are made up of two or more tissues to characterize specific function. A group of organs with related functions build up organ systems. Structure of cells, tissues, organs, and organ systems are closely related to function together to form organisms.Human body is very complex. There are numbers of muscles, bones, tendons, and ligaments. These complexion are linked and must work together in order to move besides to response signals from the brain. At certain situation due to diseases or injury of these structures, movement can be affected. The importance of understanding what are muscles, tendons, and ligaments helps to understand this research. There are four different types of tissues in human body which are epithelial tissue, muscle tissue, nervous tissue, and connective tissue. Table 2.1 shows the explanation of types of tissue.Table 2.1: Types of tissueTypes of tissue ExplanationEpithelial tissue Made up of epithelial cells, joined together to make a single or stacked layers sheet. In form of skin, makes resistance protective cover for the body.Muscle tissue Long and fibrous of muscle cells, arranged in parallel lines and bundled.For contraction, tension of muscles, and it is possible to move body parts.Nervous tissue Cells known as neurons and conduct impulses.Transmits signals and responses from nerves to spinal cord and brain.Connective tissue Provide cohesion and internal support, vary in density and cellularity.Bone, ligaments, tendons, cartilage, and adipose tissue.Table2.2: Ligament, tendon, and fasciaThere are more than 600 muscles in the body and they made up 40% of total body weight. Figure 2.1 shows the skeletal muscles and structure of skeletal muscle. The muscles basically are made of a kind of vey elastic tissues and made up of thousands of tiny fibers surrounded by a lamina. In order to form bundles of muscles, a group of tiny fibers of 40 millimeters long are bounded together by perimysium. Numbers of bundles are differ and they are enclosed by a strong epimysium, which forms the muscle fascia and continues at the ends of the muscles into tendons attached to the bones. Bundled fibers are wrapped together in connective tissue as it supports and protects muscle cells and allows to withstand contraction forces. Table 2.2 shows the explanation of ligament, tendon, and fascia.Ligament Attach bone to boneStabilize joints to moveTendon Located at each end of a muscle, attach muscle to bone.Muscle contracts, attached tendon pulls the bone to move.Fascia Attach muscle to structureSeparates muscles and other internal organs.241300232283000336232524765001543050290830Figure 2.1: Skeletal muscles and structure of Skeleton Muscle0Figure 2.1: Skeletal muscles and structure of Skeleton MuscleHeart, stomach, tongue, and lungs are examples of organ. Different kinds of tissue are composed together to structure an organ. For instance, the heart pumps blood to all parts of the body. The heart contains all kinds of tissue which are muscle tissue, nervous tissue, connective tissue, and epithelial tissue. Each tissue functions together and allows the heart pumping blood all over the body.Organ system is a group of organs that work together to conduct a major function. Each organ in the body is a part of organ system. System is the most complex organization in the body and the final progression from cells to tissues to organs and organ systems.Organs are a part of every system. Organs work together in several systems of the body. For instance, skeletal system. Skeletal system is human muscle system of composition of bones, cartilages, ligaments and other tissues that are under voluntary control, and that are concerned with movement, posture, and balance. Human muscle such as the muscles of all vertebrates is often divided into striated muscle, smooth muscle, and cardiac muscle. It is the work of the relaxing and contracting muscles that enables human to move at ease. Even, spontaneous action such as blinking of eyes require muscles to move. Therefore, an obvious movement such as walking, sitting up, and drinking water too require muscles to work. Most of the muscles work in pair with one relaxes while the other one contracts.2.2 Similarities of these two physical activitiesTwo types of physical activities involved in this research. There are walking and sitting on the chair. Both these physical activities require the most part of the leg muscles to function well to maximize the stabilization, to maintain a good posture of the body, and to prevent less injuries. Table 2.2 shows the main list of muscles involved in these walking and sitting activities.Walking Sitting Quadriceps (rectus femoris, vastus medialis, vastus lateralis, and Sartorius), hamstrings, calf muscles(triceps muscles: gastrocnemius, soleus muscle), iliopsoas, gluteus medius and maximus, Quadriceps (rectus femoris, vastus medialis, vastus lateralis, and Sartorius), hamstrings, calf muscles(triceps Surae : gastrocnemius, soleus muscle),tibialis anterior, soleus Table 2.2: Main list of muscle involved in walking and sitting In conclusion for both walking and sitting activities, the lower part of skeletal muscles are involved. Every part of muscles are connected to each other. For this research, only part of calf muscles are used. Further explanation on how to measure the calf muscles will be explained in Chapter 3 and Chapter 4. 2.3 Calf muscleCalf muscle is also known as triceps surae. Calf muscle is located at the leg part of human skeletal muscles. Calf muscle is a combination pair of two muscles. These two muscles are gastrocnemius muscle and the soleus muscle. These two muscles are both tied together and connected to the foot through calcaneus muscle which can be found at the heel of human foot’s bone. Achilles tendon can be found at calcaneus muscle. These formation of muscles formed the major part of posterior leg muscle in the human body. Besides, the triceps surae also has three heads derived from the two major types of muscles. The gastrocnemius muscle. The superficial portion of this muscle has two heads attaching to the base femur. The femur is directly connected above the knee.The soleus muscle. The remaining head of profundus muscle of this muscle forming of the soleus muscle is attached to the superior area of tibia.Table 2.3: Gastrocnemius and soleus SEQ Table_2.3:_Gastrocnemius_and_soleus * ARABIC 1Muscle Origin InsertionGastrocnemius Posterior surfaces of the femoral condyles Posterior surface of the calcaneus by way of the Achilles tendonSoleus Posterior surface of the head and upper third of the fibular shaft, and posterior tibia Posterior surface of the calcaneus by way of the Achilles tendonThe gastrocnemius muscle is a large posterior muscle of the calf in the human body. It can be found at the back of the femur of the thighbone and patella of kneecap. The gastrocnemius works when the heel is pulls up, the foot extends downward. The muscles enables force of propelling in walking and sitting up. Femur is also known as thighbone which can be found at the upper leg bone. Ball-and-socket is formed by the head of the femur and it is held in places with helps of strong ligament within the socket. Functions of calf muscle is to induce plantar flexion. It is describes as the movement that will effects the angle between two parts of the body. In the other word, flexion characterizes a bending movement that the angle of a segment and its proximal segment decreases. During plantar flexion the tendon flexes, the bone rises as the rest of connected muscle moves downward or inward. For simple example, the muscles around the fingers flex and a fist of hand clench. In this research, when sitting down, the knee are flexed and the angle between its proximal segments occurs. In addition, in the transverse plane, calf muscle ensures the stabilization of ankle complexion which include primarily movement in sagittal plane, stabilization of locomotion such as walking. Throughout process of walking, the legs tend to straight and then it bends at the knee. Knee flexion is known as when the leg is bent back toward the backside. When knee flexes, gastrocnemius muscle works together with the hamstrings, popliteus muscles bend it at the joint. Throughout the process of sitting down, the muscles around the legs change. The gastrocnemius muscles change from straight to bend at the knee. The contraction and relaxation of muscles happen at both walking and sitting down.