Biomechanics and Sports.pptx

Meaning of Biomechanics- The word biomechanics derived from Greek words bio and mechanics. Bio means life or living things and mechanics means the field of physics which deals with various forces and body movements. The study of biomechanics provide the knowledge of human body movements and the forces that acts on human movements. Biomechanics helps to know the correct movements and improve performance.

1. Helps to realize and understand the influence of mechanics on the performance.2. Helps to improve motor qualities.3. Helps the athletes in self evaluation and perfection.4. Helps to change the rules and regulations of sports.5. Helps in the development of new techniques.6. Helps in the development of new equipments and in the selection of new equipments.7. Helps in the selection of players.8. Helps in teaching and coaching and improve performance.9. Helps in the prevention, protection and rehabilitation of various sports injuries.10. Helps to determine mechanical advantages and disadvantages of in human movements.

Projectile- A projectile is any object that can be projected or thrown in the air. A projectile is a body which is thrown with some initial velocity and than allowed to be acted upon by various forces. The study of projectile is very important in sports especially in throwing events. For maximum distance the thrower must throw the object at 45* with maximum velocity. If the angle of release is grater or less than 45* the distance covered by object is less. This is because 45* is the between the vertical and horizontal and ensure the greatest amount of each component. Except angle of release it can be affected by air resistance, mass of object, shape and size of object, speed of throw and gravity etc. it is very important in the activities like shot put, hammer throw javelin throw, discuss throw, long jump, shooting in basketball, kicking in football, throwing in cricket etc.

Trajectory- A path taken a projectile (object) is known as trajectory. This path is curved in shape. E.g. shot put, hammer throw, javelin throw, football kicked, throw in cricket etc. The maximum upward distance h is reached by the projectile is called height, the horizontal distance travelled x is the range or distance and the path of object is called trajectory.

Projectile is an object that can be projected or thrown in the air. There are so many factors and forces which acts on the object and affects the movement. Some factors are given below-1. Gravity- Gravity acts on a body or object to give it mass. Gravity will affect a projectile as it will decrease the height which projectile can obtain. The force of gravity acts on the object to stop its upward movement and pull it back to earth, limiting the vertical component of the projectile.2. Air resistance-As a projectile moves through air it is slowed down by the resistance. Air resistance will decrease the horizontal component of a projectile. Air resistance acts more if the surface of object is rough , if the weight of object is less & if the surface of object is large etc.

3. Angle of release-The angle of release changes the relationship between the horizontal & vertical component of an projectile. For maximum horizontal (distance) the thrower must throw implement (angle of release) at 45 degree is half way between vertical & horizontal & will ensure the greatest amount of each component.4.Speed of release-Speed or velocity is directly related to distance. The greater speed of release , the greater distance covered by object. Having a higher initial vertical velocity will increase the height of a higher initial horizontal velocity will increase the length or distance covered.5. Height of release-The height of release refers to the height at which an object is released relative to its landing point. If a projectile or object thrown from a greater height , will cover maximum/ greater distance than a object thrown from low height.

6. Spin – The amount & direction of spin acting on a projectile will directly affect the distance of projectile. The reason for this is the air pressure acting on the ball e.g. in a tennis shot , top spin gives less distance as compared to backspin. Range is decreased with topspin & range is increased with backspin.

There are three Newton’s law of motion and are given below-● 1. First law of motion- It is also called law of inertia. An object remains in a state of rest or of uniform motion in a straight line unless compelled to change that state by an applied force.● Example in sports:● A football that is stationary will not move unless we kick it. Similarly, the golf ball on the tee does not move unless hit by the golf club.● A ball that is moving would continue to keep rolling based on this law. The reason a ball we kick does come to a stop is because of the action of either the air molecules or the ground. If the ball were moving in space it would keep moving.

Second law of motion- It is also called law of acceleration. The rate of change of momentum of a body is directly proportional to the applied unbalanced force in the direction of force. Examples-1. A baseball player hit the ball hard and forcefully to throw it far away.2. In football, a forward player who has received the ball in a strong position close to the goal will only need a impart a relatively small amount of force in the direction of the goal. However, a forward player who has been forced to edge of shooting circle before taking kick will need to impart larger amount of force in the direction of goal as the ball need a greater change in momentum to travel to the goal.3. A cricket player while catching a ball moves his hands backwards. Initially the ball is moving with a certain velocity. The player has to apply a retarding force to bring the ball at rest in his hands.

Third law of motion- It is law of reaction. It is to every action there is equal and opposite reaction.Examples-1. Springing from a diving board is an example of the action and reaction. The more force one exerts on the downward bounce, the higher he bounces into the air.2. When a swimmer pushes the water backward, this is action and the water pushes the swimmer forward that is reaction.3. It sprinting, in start when a sprinter pushes the starting block in backward direction by his feet(action), the starting block pushes him forward direction(reaction).

The word ‘Aerodynamics’ comes from two Greek words: aerios, concerning the air, and dynamics, which means force. Aerodynamics is a term of physics that describes the ability of an object to overcome air resistance. Anything that flies, such as airplanes, helicopters, and birds, utilize the principles of aerodynamics to move through the air.The 4 basic forces of aerodynamics and how they affect sports players1. Weight : The force of weight plays a major role in Aerodynamics Movement. “Weight is the force generated by the gravitational attraction of the Earth”.The force of weight plays a major role in speed. The force of weight is one of the main reasons smaller cars create less wind resistance compared to larger vehicles.

2. Lift : “Lift is the force that directly opposes the weight of an airplane in the air.” Lift can change how long you can hold your arm up when shooting a basket or serving a ball. It can also effect how hard you hit a ball because if you cannot hold your arm ready for a period of time longer than a few seconds, your arm could wear out and fall, causing you do miss the ball. You also could hit a ball, but not with nearly as much force.3. Thrust : “Thrust is the force which moves an aircraft through the air.” (NASA) Thrust overcomes the forces of weight and drag to keep something in the air, so if you jump for a shot or a spike, knowing how to use the force of thrust to your advantage can make a huge difference in how you come up to the basket, or how much force you put behind a ball being shot/spiked.

4. Drag : “Drag is the aer0dynamic force that opposes an aircraft’s motion through the air”. Drag can slow you down when you are running down the court, especially if your uniform is baggy because the uniform pushes against the air around you. This force pushes you backwards as you run through the air particles.How aerodynamics affect a ball?If you don’t put any spin on it, the airflow around the ball will be symmetric. However, if you put spin on the ball, it will start to curve. The spin on the ball imparts vorticity on the air, which causes the airflow to loose its symmetry, and for the air to curve to one direction or the other as it goes around the ball. Since the air is being pushed in one direction by the vorticity generated by the spinning ball, the air will push the ball in the opposite direction. This results in lift, and in a curveball.

Friction is the resistance to movement created by contact between two surfaces. When a body moves over another body, the force which opposes the movement is called friction. We may classify friction into two types- External friction and Internal friction1. External friction- External friction arises when two bodies in contact with eachother, try to move or there is an actual relative motion between two. It is also calledcontact friction and further divided into three types-(A) Static friction – The opposing force that comes into play when body tends tomove over the surface of another but actual motion has yet not started is called staticfriction.(B) Limiting friction- Limiting friction is the maximum opposing force that comesinto play when one body is just at the verge of moving over the surface of the otherbody.

1. External friction- External friction arises when two bodies in contact with each other, try to move or there is an actual relative motion between two. It is also called contact friction and further divided into three types-(A) Static friction – The opposing force that comes into play when body tends to move over the surface of another but actual motion has yet not started is called static friction.(B) Limiting friction- Limiting friction is the maximum opposing force that comes into play when one body is just at the verge of moving over the surface of the other body.(C) Kinetic friction- It is the opposing force that comes into play when one body is actually moving over the surface of another body. It is also called dynamic friction. It is further divided into two types- Sliding friction and Rolling friction(a) Sliding friction- The opposing force that comes into play when one body is actually sliding over the surface of the other body is called sliding friction. E.g. when a flat block is moved over the flat surface of table, the opposing force is siding friction.(b) Rolling friction- The opposing force that comes into play when one body is actually rolling over the surface of other body is called rolling friction e.g. a car wheel rolling on the road, a circular disc etc.

2. Internal friction- Internal friction which arises on account of relative motion between every two layers of liquid. It is referred as viscosity of the liquid.Importance of friction- Without friction we cannot walk, write and cannot hold the things etc. Some time we decrease the friction e.g.(a) Machine parts are oiled to avoid wear and tear.(b) The surface of billiard table and balls are made of such materials to avoid friction.Some time we increase friction e.g.(a) When ground is slippery saw dust or sand is sprinkled.(b) Tires of vehicles are made with such materials so that friction between tires and road is maximum.

Advantages-1. Friction between sports shoes and ground allows to run and walk efficiently.2. Athletes like racer and jumpers use spikes and football players use studs to have proper friction while they run fast.3.Friction enables us to hold the objects and equipments. Without friction they just fall out of the hand.4. Handles of hockey sticks, badminton and tennis rackets are covered with special tapes to increase friction.5. Magnesium powder is used by the gymnasts and javelin throwers to increase the friction.6. Telcom powder is used on carom to reduce friction.7. Now a days specially designed helmets are used by cyclist to reduce friction of air to save time and energy.8. Special light weight cycles are used by cyclist to reduce friction.9. Swimmers used special swim dress and cap to reduce water friction to save energy.

Disadvantages-1. In cycling if there is more friction beween road and tires, there will be more wastage of time and energy of the cyclist. So tires must be properly inflated to reduce force of friction.2. Friction slow down the speed. Rolling shoes and smooth surface are used minimize friction in roller skating.3. Friction can cause of injuries if a player slides across the ground.4. Friction between ball and air limits how far the ball can be thrown.5. More energy is required to overcome friction.6. Friction can make the job difficult when one has to move the object . Excess friction can make difficult to slides a heavy box across the floor.7. Walk in snow or mud is difficult than a hard surface.8. Due to friction, there is wear and tear of objects and motor parts. So lubrication oils are used to allow the parts move easier and prevent wear and tear.

Method to reduce friction-1. Polishing the surface- Friction can be reduce by polishing and rubbing the surface. It reduce the unevenness and makes the surface smooth.2. Lubrication- Lubricants like oil, grease etc. are used to minimize the friction.3. Streamlining- Streamlining applies to the friction generated by the wind and liquids. By adopting a more streamlined shape, the flow of air and liquid will be smoother and easier against the surface of a particular object.4.Ball bearing and roller bearing- The use of ball bearings and rollers greatly reduces friction between surfaces, as it changes the nature of the relative motion between the surface from sliding to rolling.

Method to increase friction-1. By making the surface rough the friction can be increased e.g. soles of spikes shoes and studs.2. By sprinkling sand on wet grounds.

Our body is capable to perform so many movements and every movement takes place in one of three planes of movement i.e. sagital, frontal or transverse/horizontal and around one of three axes i.e. sagital, frontal or vertical.Planes- Plane is an imaginary flat surface along which a movement takes place. There are three planes of movement.1. Sagital Plane- It separates the left and right sides of the body or it divides the body into left and right and the movements in sagital planes are-a. Flexion such as arm curlb. Extension such as triceps kick back, leg extensionc. Hyperextension like back bendd. Front tuck, standing on toes or heels etc.etc.2. Frontal Plane- It separates the front and back sides of body or divides the body into front and back and some common movements in this plane are-a. Abduction such as raising straight leg towards side.b. Adduction such as lowering raised leg towards normal position.c. Cartwheel , sideways bending etc.

3. Transverse Plane- It separates the top and bottom parts of the body or it divides the body in top and bottom and the movements in this planes are-a. Rotation like head, neck, trunk, hip rotation.b. Supination like palm rotate outward to face upwardc. Pronation like palm rotate inward to face upward

2. Axes of Movement- An axes is an imaginary line about which the body or limb rotates. There are three axes of movement-1. Sagital Horizontal Axes- Invisible line that travels from front to back side of body.2. Frontal Horizontal Axes- Invisible line that travels from left to right side of the body.3. Vertical Axes- Invisible line that travels from the top of the head to bottom of the feet.

There are several types of movements and divided into the following categories-1. Flexion and extension2. Abduction and adduction3. Rotation4. Circumduction1. Flexion and extension-a. Flexion- Flexion takes place when the angle decrease between two bones attaches to the joint being affected. When we flex our elbow joint, the angle between humer (upper arm) and ulna, radius (lower arm) decreases. E.g. arm curling, squats, tuck jump etc.b. Extension- It is opposite to flexion. Extension occurs when the angle between two bones increases. When we straighten our knee joint the angle between upper leg and lower leg increases. E.g. leg stretching, arm stretching etc.

2. Abduction and adduction- These two movements are in the frontal plan and around a sagital horizontal axes.a. Abduction- It is a movement laterally away from the middle of our body. From standing position, when we move our leg to the side away from the middle of our body we are abducting our leg. E.g. sideways dumbbell raise with arm.b. Adduction- It is opposite to the abduction. When we return our leg from abduction to normal position.



Major Muscles involved in RunningOur primary muscles while running will include our quads (quadriceps femoris), hamstrings, gluteus maximus , illopsoas, and our calf muscles.QuadricepsThey work together to straighten our knees and bend our hips.Hamstrings and Gluteus MaximusOur hamstrings are made up of four muscle-parts on the back of our thighs. These four parts of our hamstrings allows us to flex our kneesThe gluteus macimus , is the largest of the gluteal muscles. It is the muscle that contributes most to the shape of the buttocks.

Hip Flexors (Iliopsoas)Our hip flexors (or iliopsoas), is comprised of a muscle group which work together to help our hips fllex.Calf MusclesOur calf muscles are located on the back of our lower leg, below our knee. Our calf muscles allow us to flex our knee and planter flex our ankle.Major Muscles involved in JumpingQuadricepsThe quadriceps rest on the front of the thighs. During a jump, you perform hip flexion and knee extension, both activate the quadriceps.HamstringsThe hamstrings are opposing muscles to the quadriceps and have an opposite function. You activate your hamstrings through hip extension and knee flexion.

Hip FlexorsThe hip flexors run from the lower stomach to the top of the thighs. These our muscles get activated when you flex your hip, in similar fashion to the quads.CalvesThe calves have two parts – the gastrocnemius and soleus. These parts function to plantar-flex the foot. This motion occurs when you jump off the ground and point your toes downward.Major Muscles involved in ThrowingShoulder MusclesThe deltoids are the muscles of your shoulder, which play a crucial role in rotating your arm.

TricepsYour triceps are located on the back of your upper arm and aid in the process of extending your arm at the elbow. This action helps you release the ball with force and push it in the desired direction.Latissimus DorsiYour latissimus dorsi, often referred to as your lats, are located on either side of your spine. These large muscles help produce force for throwing and help transfer energy from your legs to your upper body.AbdominalsAbdominal muscles facilitate the transfer of power from your lower body to your upper body.QuadricepsThe quadriceps is the major muscle group located on the front of your thigh. Thus large group of muscle tissue helps you power the ball toward your intended target as you step into your throw.