Introduction to Kinesiology - Case Study Example

Question 1 A projectile thrown at a distance through the air is affected by a number of parameters. This range from the throwing stage to the path the projectile goes through. In this case, an athlete is trying to throw a ball small in size and weighing up to about 0.160 kg to achieve the maximum distance of throw. The ball is affected greatly by the friction between the ball and the air as it moves through the air. A rough surface implies a lot of drag on the ball hence reducing the power in the ball(GREENE & ROBERTS, 2005). The heavier the ball the more the energy it can have to travel in the air if thrown at a higher speed. The projectile (the ball) is directly affected by the speed at which it is thrown by the person. The other critical parameter that affects the ball is the angle of projection. A steep projection from the arm orientation will increase the drag on the ball as a result of gravity. And would cover a shorter distance. The best angle of projection would be a diagonal launch from the arm of the athlete. A more horizontal throw subjects the ball to a higher gravity as well. The athlete can only determine the angle of launch for the projectile and the initial speed depending on their fitness. Any subsequent performance is affected by these two parameters. In order to analyse the performance, 4 sensor markers would be placed on the athlete. This would be strategic to measure the athlete’s muscular activity. One marker would be attached at the wrist to measure various changes in the acceleration of the arm as it rotates to release the ball(GREENE & ROBERTS, 2005). The maximum altitude at which the ball is released would also be measured as it determines how far the ball moves. A sensor marker would also be attached to the biceps to record the spin angle of the shoulder. The third sensor will be tied round the waist. This would enable us to record the movement of the trunk of the athlete as they rotate into a throwing position. The stride foot would also enable us record more force values that would enable us identify the release force of the projectile. The sensors will allow for collection of data in a 3D format which can help in simulation for the data for further analysis to identify ways of improving the performance of the athlete. Three sets of data collection would be recorded to use the average which increases the accuracy of the data. The athlete to be used in the data collection must have had extensive training in a sport which involves throwing a projectile such as a cricket player, baseball or a javelin thrower. A cricket or baseball player is preferred in this case. They will need to warm up to the task to ensure their muscles are at full performance. This will also limit the chances of injuries to the athlete(VINCENT, 1994). The throws that will record the longest distance will be used for the analysis using both statistical and probability analysis. Simple regression for instance would help predict the maximum throw depending on the results and improvements noted from the performance results. These would be well represented by three dimensional models. Question 2 Running in terms of the gait cycle would refer to the locomotion achieved by forward propulsion of the centre of the gravity of the body using the limbs with the minimum force possible. This ocurs at a faster speed such that the feet of the person appear to be suspended in the air. Walking gait would also refer to the movement of the athlete or a person in slow cycles where the time frame between one leg touching down and the other living the ground is almost the same(HOFFMAN, 2013). Thus in the walking gait, the athlete appears to be supporting himself on one leg at a time while moving the other, and the two limbs interchange roles in a rather smooth coordination. In order to establish the marginal speed that determines the transition from the walking gait to the running phase, the amount of force required to keep the athlete suspended in the air for about one and a half a second would be measured by the force plates. Once recorded, it is possible to determine the transition face when the suspensionpower is attained. Anything below will represent a walking gait. Once the transition phase is identified, the speed can be calculated by the runner by measuring the distance covered and comparing it with the time taken to cover the distance. To achieve the results of this experiment, the equipment to be used will include, force plates, stop watches to determine the time and cameras to record the movement and allow for the transition to be registered. The force plates are the most important instruments in this case that would be used to determine the transition phase and hence the speed. Question 4: Gait Analysis Gait analysis is the organized study of animal locomotion particularly the study of human movements with regard to the eyesight and brain observations as well as the use of diverse instruments in measurements of body movements, body mechanics and muscle activities. It is an efficient mechanism of that enables the identification of posture-associated technicalities in people with injuries. In addition, it encompasses the introduction and analysis of the measurable parameters of gaits and the resultant patterns. Thus, gait analysis is a common phenomenon in sport mechanics and physical exercise activities. A study on human gait In a gait laboratory, several cameras are placed around a treadmill, which are linked to a computerized system. The person to be investigated is then attached with markers at various parts of the body for instance the spinal area, ankles as well as the knee condyles just to mention a few(GREENE & ROBERTS, 2005). The next step is the patient walking down the treadmill as the computerized system keeps on calculating the trajectory of every attached marker in 3D. A model machine is then fixed to calculate the locomotion behaviour of the underlying bone configurations. Therefore, a detailed breakdown of each joint movement is recorded and then utilized for further analysis. Achievements The above-illustrated procedure for carrying out a research of the gait analysis of humans is an essential procedure, which encompasses the following achievements. Accurate gait procedures aid in providing the quality advice required by the athletes in their sporting activities as it enables them to keep track of the various defects that may arise in their career. It facilitates a quick revelation of the defects that may not be realized from mere observation as well as physical examination facilitates a reduction of the hospital admission associated costs. Keeps ultimate treatment costs at low levels that can are affordable. Shortcomings Realistically, in the standard gait cycles, the motion and phases are always headed towards the same direction either to the distal end or to the proximal end as opposed to the assumptions that are normally employed to obtain the required data. The normally utilized decelerators always remain unused, unloaded or overused in the oblique-based direction depending on the phase and limb mechanisms. b) Aims of the study To reduce the effects of over-pronation as well as under-pronation To provide adequate and essential information about the running styles of sportspeople To reveal the need for inward foot rolling as a shock absorber mechanism for the legs and entire body in the process of running To reduce the overall risks associated with running and facilitate running efficiency To provide relevant information in determining the right type of running shoe to choose in order to minimize the shoe-related injuries c) In the course of gait study, the application of diverse equipment to obtain the desired results is ideally fundamental. The kinesiology laboratories are always equipped with the floor- mounted load transducers, which facilitate the measurements involving ground response forces, moments, magnitudes direction and their associated locations. The distributed spatial forces can as well be measured using the pedobarography machine. These measurements aid in the calculation of the resultant equations that are based on the Euler Newtonian equations, whose computations are normally referred to as inverse process of dynamics(VINCENT, 1994). In addition, the utilization of the surface electrodes is another key feature in determining the electrical activity of for instance single muscle elements, this result to an easy process for further determining the activation durations, degree as well as magnitude of activation(GREENE & ROBERTS, 2005). Consequently, this leads to the establishment of the electromyogram (EMG) patterns, which are applied in diagnosis of diverse pathologies to predict the outcome of treatments. Thus, the usefulness of the training programs offered to sportspeople is ultimately ensured. d) The gait analysis is a modulated approach that entails a myriad of criteria whose incorporation in the gait investigations serves a critical function in getting the required data for use. Through a careful study of such factors, the parameters that are taken into account in gait analysis are established. They can be categorized as: Extrinsic factors Intrinsic factors Physical factors Psychological as well as pathological factors The choice of these factors depends on the required type of data required. Intrinsic factors which include, gender, mass, stature and age are mostly utilized in gait analysis. Taking into consideration the gender of the participants in gait analysis, various parameters can be of essence. They include among others Length of the steps, Length of the strides Velocity, Foot angle, Angle of the hip and so forth. The applications of psychological and physiological parameters needs to be avoided for achievement of better results since these parameters are subject to variationsVALENTINE, VALENTINE & HETRICK, 1989). On the other and the observance of respect and mutual understanding of one another are among the ethical issues that cannot be underestimated in the gait analysis process. The occurrence of trauma and mental stress anomalies are among the hazards that may arise in due course. The use of well-equipped laboratories and making the exercise less strenuous can serve to curb these anomalies as the investigative process continues(GREENE & ROBERTS, 2005). Question 9: Angular Momentum Angular momentum refers to the product of the moment of inertia of a body about an axis and its angular velocity with respect to the same axis of rotation. Angular momentum is a vector quantity in which the vector points in an upward manner along the anticlockwise axis. Calculation for angular momentum Courtesy of VALENTINE, T., VALENTINE, C., & HETRICK, D. P. (1989).Applied kinesiology: muscle response in diagnosis, therapy, and preventive medicine. Rochester, Vt, Healing Arts Press. Thus, the angular momentum of a rigid object is given by performing a simple multiplica5tion of inertia associated with a body and the angular velocity of the same body. Angular momentum = Courtesy of VALENTINE, T., VALENTINE, C., & HETRICK, D. P. (1989).Applied kinesiology: muscle response in diagnosis, therapy, and preventive medicine. Rochester, Vt, Healing Arts Press. When given a mass of a body or particle, which is under rotational forces, then the angular momentum of the body can as well be calculated using the formula: L = mvr sin θ Where m represents the mass of the rotating body, v represents the angular velocity, r is the radius of rotation of the object and θ represents the angle of rotation of the body in circular motion. Consider the following diagram. L = mvr Courtesy of VALENTINE, T., VALENTINE, C., & HETRICK, D. P. (1989).Applied kinesiology: muscle response in diagnosis, therapy, and preventive medicine. Rochester, Vt, Healing Arts Press. b) Comparison between angular and linear momentum Differences P (which represents linear momentum) =M*V, L (angular momentum) = r*p this implies that they have different units. Angular momentum isjust the linear momentum multiplied by distance. If a time derivative of MV is taken then the resultant quantity is (ma) so the rate of change of this momentum is equivalent to the resultant force in action. The interior forces cancel out by the equal and opposite forces due to the rulesuch that you are left with only exterior forces(GREENE & ROBERTS, 2005). If there are no exterior forces the rate of variation of momentum is zero, consequently it does not deviate hence force conserved. For angular momentum,if a time derivative is taken, then the resultant quantity from r*p is r*F which is equal to torque. By the same reason, only the external torqueses that are left,therefore, if there is no force then the direct implication is that there no variation in linear momentum. The absence of torque implies no change in angular momentum. The thought behind them is similar; one is just the rotational correlation of another however, they are entirely different(GREENE & ROBERTS, 2005). If something is moving in a circular manner, then r and p are vertical to each other and as a result, v can be expressed as ω*r turning r*p, r*m*ω*r = m*r2*w I = m*r2hence I*ω A summary of the above illustration can be given as: Linear momentum is measured in kilograms, meters per second (Kgm/s) while angular momentum is measured in kilograms meters square, radian per second (Kgm2rad/s). Linear momentum is said to be parallel to motion under consideration while angular momentum is said to be perpendicular to motion under consideration. Torque is required for a change to occur in angular momentum wile a force is required for a change in linear momentum to occur. The similarity, which exist between linear and angular momentum, is that: They both deal with momentum They have similar equations c) The spinning velocity will decrease. The fact that angular momentum is a conserved quantity, where r is the radius representing the vector of rotation, implies that for each particle making the spinner’s body, the contribution due to the magnitude of the total angular momentum, is given as m*r*v. Thus, the opening of her arms increases the radius for the building units of her rotating body. In order for the conservation of the momentum to take place, then the spinning velocity will reduce considerably. This is because the angular momentum must be maintained constant(FROST, 2002). List of references FROST, R. (2002). Applied kinesiology: a training manual and reference book of basic principles and practices. Berkeley, Calif, North Atlantic Books. GREENE, D. P., & ROBERTS, S. L. (2005). Kinesiology: movement in the context of activity. St. Louis, Elsevier Mosby. HOFFMAN, S. J. (2013). Introduction to kinesiology. Champaign, IL, Human Kinetics OATIS, C. A. (2004). Kinesiology: the mechanics and pathomechanics of human movement. Philadelphia, Lippincott Williams & Wilkins. VALENTINE, T., VALENTINE, C., & HETRICK, D. P. (1989). Applied kinesiology: muscle response in diagnosis, therapy, and preventive medicine. Rochester, Vt, Healing Arts Press. VINCENT, W. J. (1994). Statistics in kinesiology. Champaign, IL, Human Kinetics. Read More