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Sport Science - your best bet to beat competition when used in a correct and legal way

How can you achieve these targets in sport: "Faster, Higher, Stronger"?

Very often people in this part of the world wonder why some developed countries do very well in Olympics and other International sporting competitions and get the maximum number of medals/cups. There is a secret here. If you don't know it yet, we are going to unravel it for you in big letters:

SPORT SCIENCE!

Yes, it can take you to great levels of Citius, Altius, Fortius.

Sport science is a discipline that studies how the healthy human body works during exercise, and how sport and physical activity promote health from cellular to whole body perspectives. The study of sports science traditionally incorporates areas of physiology (exercise physiology), psychology (sport psychology), anatomy, biomechanics,biochemistry and biokinetics. Additionally it also deals with injuries and other medical issues like mechamisms of performance, pathology. adaptation, aging and exercises, blood and drug tests, hormones (Endocrine System), illness, acclimatization to various environmental conditions during high altitude sports, heat acclimatization, jet lags ( as sport persons have to travel all over the world), excercise induced injuries, metabolic conditions, drug abuse and doping, drug and supplement use and their side effects, nurtritional aspects of sports persons, heart conditions and sudden deaths in the field and several other things associated with sports.

It enlightens on how better tracks or equipment can help people in the sports arena.

If you want to run or swim faster, it helps you how to do it without injuring yourself. What type of boots can take the pressure out of your leg joints while you are doing your best in the arena (trust the research that comes out of un-attached research institutes instead of the ones that out of commercial establishments). What running technique suits you and the track! How can you overcome the wind force and moisture (in the atmosphere) and water drag in a pool. What type of clothes you should wear to beat these forces of obstruction. How should your feet land while running or jumping.

How to boost your stamina and fitness. Why fatigue happens and what limits one's performance.

This limitless field of sport science can take you to several unknown lands and makes you wonder why we are not using it to its full potential to give tough competition to the best performers in the world!

There is some idea in the public domain - that you slow down because you run out of oxygen, you become anaerobic, lactate forms and “poisons” the muscles, or you get too hot and your brain says “stop!” The good old books explain how muscle becomes fatigued as a result of these chemicals that build up, caused by a lack of oxygen delivery as you get closer to the VO2max (the maximum or optimum rate at which the heart, lungs, and muscles can effectively use oxygen during exercise, used as a way of measuring a person's individual aerobic capacity), where you can’t use any more oxygen.

But how can you speed up in the last leg of running despite all these adversities? When you are supposed to run quite a lot faster than your “anaerobic threshhold”, which is always defined as the speed/intensity above which you start to accumulate lactate to beat others?. One thing we do know, is that in a 10km race, with 1km to go, there’s a lot of lactate in the system! Similarly, you can be pretty much guaranteed that with 1km to run, the calcium channels are at their most leaky, the phosphate and H+ ions are at their peak, and the body temperature is at its highest and your muscles are becoming weaker and weaker because of chemicals like lactate, or a lack of oxygen! Then how to go through the opposite when you have to get slower according to Nature rules?

According to a new theory which is called “Anticipatory Regulation” by its proponents ...

During exercise, the brain regulates performance to balance all the body’s physiological systems
Fatigue (or the slowing down in pace) is the result of this regulation, which happens BEFORE any physiological “failure” can occur
Therefore, rather than slowing down AS A RESULT of lack of oxygen, high body temperatures, high lactate levels etc., you slow down IN ORDER TO PREVENT THEM.
Performance and fatigue are regulated to prevent the potentially harmful limits from being reached. These “limits” to exercise are real. If your body temperature is above 41 degrees, you’d stop and be in serious trouble. If you did accumulate too much hydrogen, it would be bad news. But when exercise takes place, they don’t happen because the brain is in control, and it regulates the body specifically to protect against that damage. At the same time, it’s trying to balance protection with your own desire to perform as well as you can, and that produces a constant balance between two potentially conflicting goals.

In this theory, then, you get what is called a “pacing strategy,” which is the output by the muscles, as part of this regulation. Performance is regulated, not determined, by the physiology.

And years of practice and exercise makes this possible!

Oxygen provides energy for most living objects. In the atmosphere, oxygen is 20.95% of the air we breathe at sea level. Normally the athletes are breathing 20.95% oxygen, 78.09% nitrogen and about 1% other gases like CO2 and argon. If the athlete works out at high altitude, he will face a different situation. Because the density of the air is thinner and the volume of oxygen available to the lungs is less. In time the lungs adjust to thinner air. This may be the reason the U.S. Olympic Training Center is located in Colorado Springs, CO. Where the volume of oxygen is less than found at sea level. Training in Colorado Springs conditions a person's lungs to function normally with less oxygen. Living at altitude boosts red blood cell concentrations, allowing them to supply oxygen to muscles at higher-than-normal rates. As a consequence, VO2max should improve, enabling athletes to perform better – and for longer. Viewed in this way, altitude training is a legal form of ‘blood doping’. Although altitude training is positive , it also has negative impact! The problem is that while altitude chips in a few more red corpuscles, it also chips away at overall fitness because of the lower quality of training which is carried out at elevation. This viewpoint is also a reasonable one: scientific research has shown that when athletes journey to altitude, the quality of their workouts usually declines significantly, unless they are 100m sprinters involved in nothing more than short-duration highly intense training.

Conversely, if training or competing at sea level, one can breathe a higher volume of oxygen to increase performance.

One trick some of the athletes employ is - increase their blood oxygen level before they compete. For example, if they bring their oxygen level up to 99 or 100 percent they will have more time before they need to stop and rest. Pre-exercise oxygen has been studied in athletes like 800m sprinters, 200m swimmers and weight lifters, and generally the results have been positive. That is, breathing in pure oxygen before the start of a high-power exertion seemed to shorten the time required to cover a fixed distance or lift a set number of weights. But athletes cannot take oxygen tanks to their start lines. In the studies where oxygen boosted performance, the athletes involved knew that they were breathing in pure oxygen, and thus a powerful placebo effect may have enlivened their performances. No ‘double-blind’ research has ever linked pure oxygen breathing and heightened performance in a convincing way. The one time when breathing in extra amounts of oxygen can be very helpful is during exercise.

Yes, using natural oxygen levels in the atmosphere by your body to the optimum levels can be helpful. Special exercise makes this possible. The issue isn’t how much oxygen we bring in. It’s how much we utilize. Bringing in more oxygen isn’t actually adding to our ability to utilize the oxygen we do have, according to experts. There’s no real justifiable physiological reason for doing it.

So the best way to improve one's performance is to focus on one's training, nutrition and recovery. The large majority of benefits and the ability to compete at high levels are going to come from your daily training regimen. This is the bottom line, according to recent research in science!

Energy drinks normally contain high levels of caffeine, sugar and other chemicals that provide energy. Not considering the negative aspects of their ingredients, it is proven that oxygen provides 80 percent of the energy required by the body and only 10 percent of one's energy comes from what they consume.

All this knowledge can help a sports person if s/he is trained and assisted by experts in a right and legal way.

However, Some sport persons use extreme games of biology and indulge in illegal methods. Fake abilities can be obtained by Blood Doping. It refers to a handful of techniques used to increase an individual's oxygen-carrying red blood cells, and in turn, improve athletic performance.

Three widely used types of blood doping are: blood transfusions, injections of erythropoietin (EPO), injections of synthetic oxygen carriers.

Illicit blood transfusions are used by athletes to boost performance. There are two ways to do this:

Autologous transfusion. This involves a transfusion of the athlete's own blood, which is drawn and then stored for future use.

Homologous transfusion. In this type of transfusion, athletes use the blood of someone else with the same blood type.

The most commonly used types of blood doping include injections of erythropoietin (EPO), injections with synthetic chemicals that can carry oxygen, and blood transfusions, all of which are prohibited under the World Anti-Doping Agency's (WADA) List of Prohibited Substances and Methods. EPO is produced naturally by the body. The hormone gets released by the kidneys and causes the body's bone marrow to pump out red blood cells. Red blood cells shuttle oxygen through a person's blood, so any boost in their numbers can improve the amount of oxygen the blood can carry to the body's muscles. Then end result is more endurance.

Blood transfusions involve drawing out your own blood and storing it for a few months while your body replenishes its red blood-cell supplies. Then, before the competition, the athlete would re-inject the blood back into his or her body. The outcome is similar to that of EPO — a bump in red blood cells. WADA suggests there has been a resurgence of blood transfusions with the introduction of an EPO-detection method in 2000. For athletes, the extra bump can mean the difference between a gold and silver, or whether or not you break a world record. It is clearly enough to give you a substantial edge in international competitions if you are an elite athlete.

Microorganisms have been developed to produce human recombinant EPO, which appears very similar to the body's natural EPO. In low quantities it is good enough to enhance the performance but becomes difficult to detect! Some of these compounds have short-acting periods of time in the body, but the biological effects, the positive effects on performance, can be weeks or months.

Synthetic oxygen carriers. These are chemicals that have the ability to carry oxygen. Two examples are: HBOCs (hemoglobin-based oxygen carriers), PFCs (perfluorocarbons).

Synthetic oxygen carriers have a legitimate medical use as emergency therapy. It is used when a patient needs a blood transfusion but when human blood is not available, there is a high risk of blood infection and there isn't enough time to find the proper match of blood type.

Athletes use synthetic oxygen carriers to achieve the same performance-enhancing effects of other types of blood doping: increased oxygen in the blood that helps fuel muscles.

So for every unusual performance, there might be a reason of misuse of science.

But serious health hazards await sports persons using these performance enhancers. They get addicted to it without which they think they cannot perform. The blood count gets too high, the blood gets too thick, and it becomes hard for the heart to push the blood around the body or that somehow this high blood count contributes to somebody having a stroke or a blood clot. 

Testosterone, an anabolic steroid, is another popular drug for abuse (3). Anabolic steroids may block the effects of hormones such as cortisol involved in tissue breakdown during and after exercise. This would speed recovery. Cortisol and related hormones, secreted by the adrenal cortex, also has receptor sites within skeletal muscle cells. Cortisol causes protein breakdown and is secreted during exercise to enhance the use of proteins for fuel and to suppress inflammation that accompanies tissue injury. The real effect of anabolic steroids is the creation of a "psychosomatic state" characterized by sensations of well being, euphoria, increased aggressiveness and tolerance to stress, allowing the athlete to train harder. Such a psychosomatic state would be more beneficial to experienced weight lifters who have developed the motor skills to exert maximal force during strength training. Diets high in protein and calories may also be important in maximizing the effectiveness of anabolic steroids.

But users livers get effected adversely. They might also suffer from anemia, renal insufficiency, impotence, dysfunction of the pituitary gland, hyper tension, bleeding, hepatocellular carcinoma ( cancer of liver), compromised immune system and loss of hair (4).

Other abused biological molecules include synthetic versions of human growth hormone and luteinizing hormone, which is involved in testosterone production. These hormones present challenges in detection to antidoping researchers.

But science is catching up with bad science users. Most of the methods for detecting these doping agents rely on biochemistry, chromatography and mass spectrometry.

Genetic manipulations: Gene doping is certainly attractive to manipulate muscle, blood and pain-perception systems – anything that enhances the ability to train and to deliver blood to exercising tissues and to increase endurance or explosive muscle function. If an athlete were ever to be in a position to add an extra gene of EPO or growth factor, they can gain a significant advantage. And although it isn’t yet reality it is definitely on the radar of WADA and science is racing ahead of cheating athletes in this regard. There have been some high-profile instances of very prominent athletic trainers making attempts to obtain genetic tools, like the viral vectors that express transgenes. There is a case of a German trainer, Thomas Springsteen, who was arrested and brought to trial in 2006 for making attempts to obtain Repoxygen, a drug that was in preclinical trials to put an erythropoietin gene into patients suffering from bone marrow failure from chronic kidney disease or cancer.

Since the late 1990s, researchers have shown that, by inserting genes into mice and other animals, they can swell the animals' muscle mass, help cells repair themselves faster and boost the production of oxygen-toting red blood cells. The genes can be injected directly into the muscles of the target animal or slipped into the animal's own DNA by means of viruses. Gene therapy is called “gene doping” when it is used for enhancement rather than treatment.

Gene therapy  when used can have very serious health risks, such as toxicity, inflammation, and cancer. Moreover, the athlete's immune system would need to be suppressed, so the body doesn't try to fight off what it identifies as a virus. It's a dangerous process that will take a long time to perfect.

WADA researchers have some interesting concepts in the works, such as looking for the molecular signatures of doping. “When an athlete dopes with a substance or a cocktail of substances, she or he is looking for a physiological impact. It’s to enhance transfer of oxygen, muscle mass and other different physiological capabilities. These create an imbalance in the body’s homeostasis that they believe will be reflected at different -omics levels. A challenge researchers are facing is distinguishing between signatures caused by physical exertion, which elite athletes do intensely, and those signatures caused by doping (1).

New research suggests that a small, constrictive band that wraps around an athlete's arms or legs may lead the next wave ofperformance-enhancing fads in competitive sports.

A study published in the journal Medicine and Science in Sports and Exercise (5) demonstrated that highly trained swimmers that used a blood pressure cuff to restrict blood flow to their arms a few minutes before maximum-effort time trials improved their performance in a 100-metre race by 0.7 seconds. The study team was led by Greg Wells and Andrew Redington at the University of Toronto's Hospital for Sick Children.

So, in just a few minutes' time and with minimal effort, athletes were able to significantly boost their performance, making gains that -- according to the authors -- would normally take an average of two years of intense training to accomplish. It was earlier found that ischemic preconditioning to protect the cardiac muscle during a heart attack made less damage to hearts and recovery periods small. This technique is being used to protect different types of muscle tissue from the stress and damage that occurs during another type of ischemic event, like exercise. The researchers found that the subjects performed better when they underwent ischemic preconditioning before the exercise trial, touting gains in both maximum power (1.6 percent) and peak oxygen consumption (3 percent). All of the researchers investigating ischemic preconditioning seem to agree that temporarily reducing the blood flow to a tissue causes protective molecules to be released into the bloodstream. Ischemic preconditioning may cause vessels to dilate once blood starts flowing again, increasing nutrient and oxygen delivery to the formerly deprived tissue. Scientists think altered metabolism of mitochondria -- the energy powerhouses of muscle cells -- may contribute to more energy available for exercise.

Fitter, Faster, Higher and Stronger

Are you a medal monger?

Aim to be a dream competitor?

In pursuit of  right honour?

Want to be in the field longer?

Science can assist you with all the knowledge it can garner!

While Biomechanics will remove your worry

The field that  makes you a super man is Biochemistry

Provide the best boots that can prevent injury

And impress the public jury

Take all the cups you can carry!

To make your  rivals fury!

Now we are about to deal with complex part of sport science and it takes a bit of prior knowledge and more concentration to understand. I tried to explain it in as simple terms as possible but couldn't go beyond certain limits. Sorry about that. But go ahead and read it if you really want to add more matter to your knowledge kit.

Biomechanics is the study of the structure and function of biological systems by means of the methods of “mechanics.” – which is the branch of physics involving analysis of the actions of forces. Sport biomechanics is an interesting field that helps sports persons. It is necessary to have a good understanding of the application of physics to sport, as physical principles such as motion, resistance, momentum and friction play a part in most sporting events. In relation to sport, biomechanics contributes to the description, explanation, and prediction of the mechanical aspects of human exercise, sport and play.

Main aspects of Bio mechanics (6):

Mass: Mass simply means substance, or matter, and is typically measured with the units of pounds (lb) or kilograms (kg). People often interchange mass with weight, but scientifically these terms mean two different things. If an object has substance and occupies space, it has mass. Mass is the quantity of matter that the object takes up. Weight, on the other hand, is this quantity of matter plus the influence of gravity or, more precisely, gravitational force. So for all our studies on Earth, where the acceleration (measured in meters per second squared, m/s2) due to gravity is pretty constant (at 10 m/s2), weight is simply mass multiplied by the gravitational force, 10. For example, someone with a mass of 100 kg will have a force of weight (measured in newtons, N) of 1,000 N. So for coaches, athletes, and sport scientists, mass is the most common term we should use, and weight is the force this mass generates.

 We frequently talk of some sportsmen being massive or having tremendous body mass, indicating that the athletes are enormous and have plenty of muscle, bones, fat, tissue, fluids, and other substances that make up their bodies. Athletes who want to perform well in their chosen events carefully monitor their body mass. They know that too much or too little mass can seriously affect their performance. For all of us, checking our body mass is a means of assessing our general health and fitness. When we get on a scale, the dial gives us a reading that we associate with the amount of body mass that we carry around. 

Weight: In mechanical terms, an athlete’s weight represents the earth’s gravity pulling on the athlete’s body. The readout on the scale represents how much pull or attraction exists between the two. The earth pulls the athlete downward. So an athlete with more body mass compresses the springs to a greater extent than an athlete who has less body mass. 

Inertia: Inertia means resistance to change. If an object is motionless it will “want” to remain motionless. If it’s moving slowly it will want to continue moving slowly, and if it’s moving fast it will want to continue moving fast. If we are looking at something moving, then the mass of the object will directly relate to the inertia. Which is harder to throw, or get moving, a men’s shot put (16 lb or 7.3 kg) or a tennis ball (2 oz or 56 g)? Naturally, the shot put is harder to get moving; so the greater the mass an object has, the more inertia it has too. We must also consider one more important characteristic of inertia. Once on the move, objects always want to move in a straight line. They will not willingly travel around circular pathways; it’s necessary to pull or push on them to produce a curved pathway. A ball thrown by an outfielder would travel in a straight line following its release trajectory were it not for air resistance slowing it down and gravity curving its flight path toward the earth’s surface.

The more massive an athlete, the more the athlete’s body mass resists change. A giant 300 lb (136 kg) athlete needs to exert great muscular force to get his body mass moving. Once moving in a particular direction, the athlete must again produce an immense amount of muscular force to stop or change direction. Athletes with less body mass have less inertia and therefore need to apply less force to get themselves going. Likewise, they need less force than a more massive athlete to maneuver or stop themselves once they’re on the move.  Heavy athletes must apply tremendous force to get their body mass moving and then apply a huge amount of force to change direction or to maneuver the great masses of their opponents.

 In sports like squash or badminton, it’s possible for the immense mass and inertia of huge athletes to work against them. It’s no good being massive when sudden and varied movement changes are required unless you have the power to move your mass quickly and to control it once it’s moving. Massive athletes tend to have a poorer strength-to-mass ratio than do smaller, less massive athletes; so they have a tougher time stopping, starting, and changing direction. That’s why badminton and squash players are lean, lightweight, and anything but massive. If you’re a small, lightweight squash player, you can get a lot of pleasure from making your massive opponent crash into the side walls. You have a friend helping you in the court—your opponent’s inertia!

 An interesting example of inertia at work occurs when athletes are in flight. Consider two athletes who decide to bungee jump from a bridge. One athlete is twice as massive as the other. They step off the bridge at the same instant. Surprisingly, they accelerate toward the earth at approximately the same rate. Because the earth attracts the more massive bungee jumper twice as much, you might think that this athlete would accelerate downward twice as fast. But this same athlete has twice the inertia of the other thrill seeker and so resists being accelerated by gravity twice as much. In this situation, air resistance plays a negligible role, and the two athletes accelerate downward at approximately the same rate.

Inertia as an enemy when an athlete wants to get moving. To defeat this enemy, it’s good if the athlete’s mass is made up of powerful muscles that are able to generate the required amount of force. Once the athlete is on the move, inertia can become a friend because the second characteristic of inertia is that it wants to keep the athlete going. The difference between resting inertia and moving inertia causes athletes to expend much more energy at the start of a 100 m dash than when sprinting in the middle of the race. The two characteristics of inertia, resistance to motion and then persistence in motion, are seen not only in linear situations in which objects and athletes move in a straight line, but also in rotary situations when objects such as bats and clubs are made to follow a circular pathway. As long as the athlete makes a base ball bat travel around in an arc, the bat will try to continue moving along this circular pathway. If the bat slips out of the athlete’s hands, it will immediately go back to its initial preference, which is to move at a constant speed along a straight line.

 In linear movement, mass is synonymous with inertia. The more mass, the more inertia. The characteristics of inertia are described in the first of Isaac Newton’s three famous laws of motion. We commonly call it Newton’s first law, Newton’s law of inertia, or simply Newton I. This law also applies to rotary situations. But rotary inertia (also called rotary resistance or moment of inertia) involves more than just the mass of the object. We also need to know how the mass is distributed (i.e., spread out or compressed) relative to the axis around which the object is spinning.  

Linear and Angular Motion:  The movement of an object can be classified in three different ways. Movement can be linear (in a straight line), angular (in a circular or rotary fashion), or a mix of linear and angular, which we simply call general motion. In sport, a mix of linear and angular movement is most common. Angular movement plays the dominant role because most of an athlete’s movements result from the swinging, turning action of the athlete’s limbs as they rotate around the joints.

 Linear motion describes a situation in which movement occurs in a straight line. Linear motion can also be called translation, but only if all parts of the object or the athlete move the same distance, in the same direction, and in the same time frame. As you can imagine, translation rarely occurs in an athlete’s movement because some parts of an athlete’s body can be moving faster than other parts and not always exactly in the same direction. For example, an athlete in the 100 m sprint wants to travel the shortest distance from the start to the finish. The shortest distance is a straight line. Yet sprinting is produced by a rotary motion of the limbs as they pivot at the athlete’s joints, and the athlete’s center of gravity rises and falls during each stride.

 Many terms are used to refer to angular motion. Coaches talk of athletes rotating, spinning, swinging, circling, turning, rolling, pirouetting, somersaulting, and twisting. All of these terms indicate that an object or an athlete is turning through an angle, or number of degrees. In sports such as gymnastics, skateboarding, basketball, diving, figure skating, and ballet, the movements used by athletes include quarter turns (90 degrees); half turns (180 degrees); and full turns, or “revs” (revolutions), which are multiples of 360 degrees. Slam dunk competitions are a great example of basketball players showing off their “360s.”

 To produce angular motion, movement has to occur around an axis. You can think of an axis as the axle of a wheel or the hinge on a door. An athlete’s body has many joints, and they all act as axes. The most visible rotary motion occurs in the arms and legs. The upper arm rotates at the shoulder joint, the lower arm at the elbow joint, and the hand at the wrist. The hip joint acts as an axis for the leg, the knee for the lower leg, and the ankle for the foot. Movements like walking and running depend on the rotary motion of each segment (e.g., foot, lower leg, and thigh) of an athlete’s limbs as they rotate around the joints.

 All human motion is best described as general motion, a combination of linear and angular motion. Even those sport skills that require an athlete to hold a set position involve various amounts of linear and angular motion. A gymnast balancing on a beam and the aerodynamic crouch position during the acceleration prior to takeoff in ski jumping are good examples. In maintaining balance on the beam, the gymnast still moves, however slightly. This movement may contain some linear motion but will be made up primarily of angular motion occurring around the axes of the gymnast’s joints and where the gymnast’s feet contact the beam. The ski jumper holding a crouched position attempts to reduce air resistance to a minimum and accelerate as much as possible prior to takeoff. Sliding down the inrun holding a crouched position is a good example of linear motion. But the athlete never fully maintains the same body position throughout, and the inrun is not straight throughout, so any motion that the ski jumper makes will be angular in character.

 Perhaps the most visible combination of angular and linear motion occurs in a wheelchair race. The swinging, repetitive angular motion of the athlete’s arms rotates the wheels. The motion of the wheels carries both the athlete and the chair along the track. Down the straightaway, the athlete and chair can be moving in a linear fashion. At the same time the wheels and the athlete’s arms exhibit angular motion (see figure 2.1). This combination of angular and linear motion is an example of general motion.

Speed, Velocity, and Acceleration: Just as the terms mass and weight are interchanged (sometimes incorrectly), a similar situation occurs with speed and velocity. While both terms indicate how fast an object is traveling, with respect to time, they have subtle differences. Speed is a scalar measure indicating how fast an object is traveling, measured by dividing the length or distance traveled by the time; but speed does not quantify the direction of travel. Velocity, on the other hand, is the change in position divided by the time.

 If an elite sprinter runs 100 m in 10 s, we know that the athlete has run a certain distance (100 m, or 109.4 yd) in a certain time (10 s). From this information you can work out the sprinter’s average speed, which is 10 m/s (10.9 yd/s), or 36 km/h (22.4 mph). And in running 100 m on a straight track, since the direction of travel is in a straight and consistent line, the change in position is also 100 m, so there is really no difference in calculating speed and calculating velocity in this instance. However, sometimes we need to know in which direction, as well as how fast, the object is traveling (i.e., north or south or positive or negative). In these situations, velocity is the better term to use. For example, when kicking a ball, as the ball takes off we can look at how fast the ball is traveling in the horizontal direction, in the vertical direction, and the resultant of these two components. To measure how fast the ball travels in these planes, we measure velocity, not speed.

The velocity that the sprinter averaged over a distance of 100 m is 22.4 mph (36 km/h)—nothing more. These numbers don’t tell you the sprinter’s top velocity, which could be as high as 26 mph (42 km/h), and they don’t tell you anything about the sprinter’s acceleration or deceleration, which is the rate at which velocity (or speed) changes. A sprinter who averages 22.4 mph over 100 m runs faster and slower than 22.4 mph during different phases of the race. Why? Because immediately after the starter’s gun goes off, the athlete is gaining velocity and for a while runs much slower than 22.4 mph. The athlete then has to run faster somewhere else in the race to average 22.4 mph over the whole distance.

 Rates of acceleration vary dramatically from one athlete to another. Some athletes rocket out of the blocks and have tremendous acceleration over the first 40 m of a 100 m race. Thereafter their rate of acceleration drops off, and close to the tape they may even decelerate. Athletes who raced against multiple Olympic champion Carl Lewis were well aware that he could still be accelerating at the 70 m mark in the 100 m dash. His rate of acceleration may have been less than that of his opponents at the start of the race, but his acceleration continued longer. Over the last 30 m, Lewis frequently caught and passed athletes who were “tying up” (i.e., breaking proper form because of fatigue) and decelerating. In the 400 m event, the 50 m velocity measures for Michael Johnson as he broke the 400 m world record in the time of 43.18 s in 1999 are shown in figure 2.2 (note that this world-record time was not broken at the 2008 Beijing Olympic Games). Johnson’s maximum velocity was at the 150 m mark, and the key difference between Johnson and the opposition was also the smaller amount of drop-off between each 50 m interval.

It is possible for athletes to reduce their rate of acceleration and still increase velocity. As long as acceleration exists, even if it’s minimal, velocity will increase. If deceleration occurs, velocity will be reduced. How much an athlete’s velocity increases or decreases depends on the rate of acceleration and deceleration.

 Uniform acceleration and uniform deceleration mean that an athlete or an object speeds up or slows down at a regular rate. An example of uniform acceleration occurs when a four-man bobsled slides down the track in the Winter Olympics and accelerates to a speed of 15 ft/s (4.6 m/s) by the first second, 30 ft/s (9.1 m/s) by the second, and 45 ft/s (13.7 m/s) by the third. For every second that the bobsled is moving, it is increasing speed at a uniform rate of 15 ft/s. You write this acceleration as 15 ft/s/s, or 15 ft/s2 (4.6 m/s/s, or 4.6 m/s2). Notice that there is one distance unit (i.e., 15 ft) and there are two time units (i.e., s/s) whenever you refer to acceleration. This indicates the rate of change of velocity, or the amount of velocity added (i.e., 15 ft/s), with each successive time unit (i.e., 1 s) that passes. If the bobsled decelerates at a uniform rate, then the reverse occurs. In this case it is slowing, or losing velocity, at a uniform rate.

 Uniform acceleration and deceleration do not happen that often in sport. When athletes (or objects such as balls or javelins) are on the move, varying oppositional forces, ranging from opponents to air resistance, cause their acceleration (or deceleration) to be varied or, in other words, nonuniform. However, one of the best examples of uniform acceleration and deceleration occurs in flights of short duration such as in high jump, long jump, diving, trampoline, and gymnastics. In these situations, air resistance is so minimal as to be considered negligible. Gravity uniformly slows, or decelerates, the athletes as they rise in flight by a speed of 32 ft/s for every 1 s of flight (i.e., 32 ft/s2) and then accelerates them at a uniform rate of 32 ft/s2 on the way down (in the metric system, approximately 32 ft/s2 = 9.8 m/s2). Sometimes you’ll see deceleration described as negative acceleration and acceleration as positive acceleration. A minus sign in front of 32 ft/s2 (i.e., −32 ft/s2) indicates that the diver is decelerating at a rate of 32 ft/s for each second that he is rising in the air.


Mechanics in sports also deals with (2)...

Acceleration0n: ( and how to overcome wind force and water drag)  - this aspect is explained above

Aerodynamics: ( related to the flow of air around a projectile, which can influence the speed and direction of the object). The air flow around a ball thrown through the air differs greatly depending on whether it has a smooth surface or a rough surface (e.g. stitches on a baseball or cricket ball, dimples on a golf ball). In the flight of a smooth ball, the air molecules travel around the ball to the back where they meet and mingle and combine to push the ball forward. The pressure behind the ball is less than the pressure in front. When the ball has an uneven surface, turbulence occurs as the air flows over the ball. The turbulence causes the air to stick to the ball just a little longer and increases the wake (as in a boat's wake) which increases drag. This makes the ball swing.

For objects in water, it is called hydrodynamics: The following forces act on a swimmer: In the horizontal direction we have the thrust provided by the arms and legs and the water drag opposing the motion, and vertically, the weight and a force of opposite direction, which in hydrodynamics is called the buoyant force.

The buoyant force is the force that allows us to float in the water. It is created due to the difference in the pressure exerted by the water at different depths. We are all aware of this if we dive under water, as our ears feel the effect. The overall result is for the body to be pushed to the surface. The value of the buoyant force depends on the density of the fluid in which the body is submerged. This revelation was enough to make the ancient Greek, Archimedes, leave his bath exclaiming the famous “Eureka”. We realize this from the fact that it is easier to float in the sea than in a lake.

The athlete produces forward thrust by use of his/her arms and legs. The exact mechanism for thrust generation depends on the swimming style (e.g. breaststroke, backstroke, etc) and the technique of the athlete. Broadly speaking, it is yet another application of the action-reaction law. The swimmer pushes the water backwards and the water exerts a force in the forward direction.
The water resistance, i.e. drag, is generated mainly due to the collision of the water molecules with the athlete and to the friction between the water and the surface of the body. In swimming, a third form of drag is created due to the waves generated by the motion of the athlete, wave drag. The appearance of waves will obstruct the efforts of the athlete. In open water events this form of drag is greater than in swimming pools that are designed so as to minimize the effect. Special types of swim wear can be designed to minimize this drag.

Center of gravity (how it effects body movements):

Here are two properties of the center of gravity that have a great impact on sport. First of all its location is dependent on the shape of the body. So if the same body is to take a different shape, the position of the center of gravity will shift. An athlete that bends his/her legs will lower his/her center of gravity position. This, amongst other things, will result in greater stability, something especially important in sports such as wrestling. Also, and this may sound the strangest, the center of gravity can lie entirely outside the body itself. For example, if the body is hollow it will literally be positioned somewhere in the air. During the Olympic Games in Mexico, in 1968, until then unknown athlete, the American Dick Fosbury, came from nowhere to teach the world about both of these properties.

The truly ingenious leap in the technique was that by clearing the bar with his back and by changing the shape of his body, the athlete could clear the bar without his center of gravity having to also clear it. By this change in body shape he was able to move his center of gravity outside his body. The energy required for a jump depends on the maximum height of the center of gravity and so by lowering its position one also lowers the energy required to clear the bar.

Centripetal forces: According to Newton, in order for the velocity of a body to change, a force must be exerted on it. This applies both to the magnitude of the velocity and its direction. When a body performs circular motion its direction is constantly changing and so is the direction of its linear velocity that is always perpendicular to the radius of the circle. This is the reason that the discus always starts its flight at a direction perpendicular to the arm of the athlete.

The force responsible for the change in the direction of a body in turning motion is called the centripetal force and always has a direction towards the center of the circular path. The centripetal force is not an independent force in the way as forces such as weight, air resistance, etc., may be considered. In order for circular motion to be possible, some resultant force must be acting on the body with a direction always to the center of the circle. This resultant force will play the role of the centripetal force. In the case of discus throwing for example, the force that acts as the centripetal force is that exerted by the hand of the thrower onto the discus. The hand is constantly turning (until the throw) so the force it exerts on the discus fulfils the aforementioned direction requirements. A similar situation occurs when a cyclist racing in a velodrome (arena for track cycling) takes a tight turn. Velodromes have track inclinations that may be higher than 45 degrees. This design helps to provide the forces acting on the athlete with the necessary direction to become centripetal.
Coefficient of restitution: The coefficient of restitution (COR) is a measure of the "restitution" of a collision between two objects: how much of the kinetic energy remains for the objects to rebound from one another vs. how much is lost as heat, or work done deforming the objects.

Basketball bounces more than a tennis ball, the reason being that when colliding with the ground it suffers fewer energy losses. So in basketball, according to the International Basketball Federation (FIBA), if a ball is dropped from 1.8m it must return to a height between 1.2m and 1.4m.

In the same way, if a tennis ball is dropped from a height of 100 inches (254cm) on to a concrete floor, it must rebound to a height between 53 inches (134.62cm) and 58 inches (147.32cm).

A basketball certainly bounces better than a tennis ball.

It is important to note that the coefficient e, depends not only on the type of ball but also on the properties of the ground. This is why the above limits are defined with respect to a concrete floor, as the tennis ball will certainly bounce differently on clay and on grass.

Energy: In a closed system, energy cannot be gained or lost. In most sporting situations, although it will seem like energy is lost or gained, what you will find is that the energy changes from one type to another. There are several types of energy, potential and kinetic energy is described here...

Kinetic energy - It is the energy of motion, described by the formula - kinetic energy = 1/2 mass x velocity^2

Potential energy - an object that is moved to a height is said to have potential energy, as if it is released it will gain speed (kinetic energy) while losing potential energy.

Force: Newton's 2nd law is where Force (F) equals mass (m) times acceleration (a), described by the equation: F = m * a

This law of physics can be related to many sporting situations like javelin throw. If you wish to calculate the force applied to an object, and you know what the acceleration and mass of the object you can use the above formula. If you know the force and the mass of the object, you can calculate the acceleration using:
a = F / m

The Physics of Motor Sports

Race Car Physics

Physics plays a great deal in the design and technique of driving a racing car.

Why are F1 race cars flat and have such as wide wheel base? It is because the wider the car, the faster it corners.

When a race car approaches a corner, without some forces applied, the car (and driver) would continue on a straight line (due to inertia). The force must produce a change in direction toward the center of the curve. The type of force that acts perpendicular to the car's velocity is called centripetal force (not centrifugal!). Centripetal force means center-seeking. It acts to change the direction of the car but not the speed.

The centripetal force is provided by the friction between the tires and the track. The force is directly related to the square of the speed of the car. If a car goes too fast, the friction force is not great enough to hold the car in the track.

The centripetal force is also inversely related to the radius of the curve. The bigger the radius of the turning circle, the less force needed to make the curve.

You may notice that the corners of some racing tracks are banked (tilted) toward the center. This is to help friction hold the cars on the track at high speeds.

Friction: Friction can be defined as the resistance to motion of two moving objects or surfaces that touch. Friction plays a very important role in many sports, such as bowling and curling.

There is both Static Friction and Kinetic Friction. Static friction is the friction before an object starts to slide, while Kinetic friction is the friction when the object is actually moving or sliding. The formula for both is the same, except they have different coefficient of friction values.

Friction Equation : When a force is applied to an object, the resistive force of friction acts in the opposite direction, parallel to the surfaces. The standard friction equation for determining the resistive force of friction when trying to slide two solid objects together is written as Fr = μN, where Fr is the resistive force of friction and N is the perpendicular force pushing the two objects together (both in units of force, pounds or newtons), and μ is the coefficient of friction for the two surfaces. The coefficient of friction varies for each situation, and is related to the two specific surfaces that are in contact with each other.
Friction in Sports : Friction plays a big role in rolling sports such as tenpin bowling and curling. In tenpin, the friction resistance on the ball makes it slow down and also enables the spin on the ball to make it roll in an arc. The mass and the surface composition of the ball and the amount of oil on the lane will affect the magnitude of the friction between the bowling ball and bowling lane. The more oil on the lane means the ball is slow down less and the harder it is for the bowler to send the ball in a curved path.
Air Resistance : Air resistance is also a form of friction, as it describes the resistance between the surface of an object or person and the air. Air resistance plays a role in many sports in which balls or other objects are thrown, and in sports in which the person moves through the air such as running and cycling. Swimmers have to contend with both air and water resistance.
Impulse: Impulse = Force * change in Time.

In a collision, the impulse experienced by an object equals the change in momentum of the object.

In equation form:

F * t = m * change in v.

Magnus force: Some of the most impressive shots taken in a soccer game are produced by applying spin to the ball. The members of the Brazilian national team were the first to use this technique for free kicks, exciting the crowds by scoring difficult goals. Since then almost all free kicks that are taken just outside the penalty box are executed in this way, helping the player to give the ball a curved trajectory, thus clearing the defensive wall and beating the goalkeeper.

So what is this force that is responsible for the deflection of the ball? The first to engage himself with the study of this phenomenon was Isaac Newton, who tried to provide an explanation for the curved paths of tennis balls (a sport particularly popular during his time). Those however who reached solid scientific conclusions were Rayleigh and Magnus in 1742, who analyzed the deflection in the path of cannon balls that spun round themselves. What they realised was that the force responsible for their curved path (and also the force that affects a football trajectory), is related to the interaction between the spinning object and the air that surrounds it. So it is yet another aerodynamic force, this time present only when an object is spinning. What essentially happens when a ball is spinning is that the rotational motion of the ball drags the air around it, so changing the direction of its flow. This, once again as a result of the action-reaction law, results in a force being exerted on the ball itself thus deviating from its original path.
Momentum: Momentum is a vector describing a "quantity of motion" or in mathematical terms p (momentum) = mass (m) times velocity (v). p=mv

Conservation of Momentum - In a closed system, such as when two objects collide, the total momentum remains the same, though some may transfer from one object to the other. Momentum is always conserved in a closed system, but most sporting situations in the real world are not a closed system. For example, when a baseball bat hits the ball, the ball will be squished to a certain degree. After few milliseconds, it rebounds back. This contraction and rebound action is causes the release of heat energy, and some momentum is lost, or transferred elsewhere.

Maximizing Momentum - As momentum is the product of mass and the velocity, you can increase momentum by increase either of these elements. In sport, examples include using a heavier bat or racket and increasing running speed or hand speed.

Angular Momentum - Angular momentum is the product of Moment of Inertia and Angular Velocity. Moment of Inertia is the angular counterpart to mass - it is the measure of the resistance of an object to changing its angular speed.

A good example of angular momentum in action is with figure skaters. A figure skater starts a spin by pulling in his arms to lessen his Moment of Inertia. By the Conservation of Momentum Principles, the angular speed must then increase. To come out of the spin, a skater simply extends her arms to increase angular momentum and decrease angular velocity.

Projectile motion: Many sports involve the throwing of a ball or other object. While discussing this the basics of projectile motion, and for ease of understanding, we will consider that there is no air resistance. The influence of air resistance, friction, spin, and air flow around the object is discussed before (see aerodynamics above).

Any projectile thrown, such as a ball, can be considered to have a vertical and horizontal velocity component, as shown in this diagram (blue=horizontal velocity component, red=vertical velocity component).

Throughout the path of the projectile, change occurs only in the vertical direction due to the influence of gravity, while the horizontal component of the velocity will not change. (This is not quite true, there will be a very small slowdown in the horizontal direction due to air resistance).

Path of a projectile

The vertical velocity of the projectile gets smaller on the upward path until it reaches the top of the parabola. At the top of the parabola, the vertical component of the velocity is zero. After that point, the vertical component changes direction and the magnitude increases in the downward direction and the vertical distance traveled during each subsequent time interval increases.

The discuss paradox: There are some sports in which wind can assist a performance in ways that may have not occurred to us. Imagine that on quite a windy day you are about to take part in the discus throwing event. The games official gives you the choice. Will you throw into the wind or in the opposite direction?

Most people would think that throwing into the wind would cause a greater deceleration and thus produce a smaller range. Although it may defy common sense though, this actually is the right tactic to follow. Simulations have shown that the discus, if thrown correctly, can travel for up to 5-6m further if it is thrown against the wind!

How can this be Possible? The answer is provided if we think of both aerodynamic forces acting on the discus. Apart from the drag, which increases due to the wind presence and so has a negative impact on the performance, there is also lift which will also increase in value due to the increased relative speed. Lift is the force that keeps the discus in the air so, the more it increases, the longer the flight.

By throwing the discus at the right angle the athlete can take advantage of this, thus overcoming the negative effect of drag. So apart from strength, discus throwing also requires quick thinking. On the other hand, it seems strange that strict wind limits have been imposed for events such as the 100m but not for others such as discus throwing where the effect is possibly greater.

Work: Measuring Work in Physics - Work is the dot product of force and displacement. In other words, the Work done is the force times the distance moved by an object in the direction of the force. This is only correct if the force is constant. Consequently, no work is done unless the object is displaced in some way. For example, if you hold a heavy object stationary there is no work done - there is no transfer energy to it - because there is no displacement.

Now you realize without sports science's aid, it is extremely difficult to win games and reach top positions. We emphasize here that it is impossible to survive and sustain in the arena called sports without the backing of big "S". Each time you enjoy an adrenaline-pumping sport or a game, think about the science behind it and people who made your entertainment highly thrilling and turned it into a great profession and made it into million-dollar-money-making- mechanism!

And don't forget to salute the sport scientists for it!

Citations:

1. https://asbmb.org/asbmbtoday/asbmbtoday_article.aspx?id=17038

2. "An Introduction to the Physics of Sports" by Dr Vassilios M Spathopoulos (book)

3. http://www.sportsci.org/

4. http://www.sportsci.org/

5. http://www.ncbi.nlm.nih.gov/pubmed/21131871

6. http://www.humankinetics.com/products/all-products/Sport-Mechanics-... (book)

There are various journals that deal with the subject

Academic journals in sports science

Journal of Applied Biomechanics
International Journal of Computer Science in Sport
Journal of Strength & Conditioning Research
Journal of Swimming Research
Sports
http://www.sportsci.org/

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Scientists throw a curve at knuckleball explanation
‘Drag crisis,’ not baseball’s seams, dictates fluttery flight paths, new study suggests
Knuckleballs baffle baseball players with their unpredictable swerves. A new study suggests a possible cause of the pitch’s erratic flight — sudden changes in the drag force on a ball, due to a phenomenon called a drag crisis.

The result is at odds with previous research that attributed the zigzags to the effect of airflow over the baseball’s seams. Scientists report the finding July 13 in the New Journal of Physics.

Knuckleballs are well known in baseball, but similar phenomena also confound players in soccer and volleyball. Knuckleballs occur when balls sail through the air with very little spin, producing unstable flight.

In drag crisis, the thin layer of air surrounding the ball flips between turbulent and smooth flow, abruptly changing the drag forces on the ball. If the transition occurs asymmetrically, it can push the ball to one side. “This phenomenon is intermittent” and hard to predict, says study coauthor Caroline Cohen, a physicist at École Polytechnique in Palaiseau, France. “We can’t know in advance [to] which side it will go.”Balls must move at a certain speed to experience a drag crisis, which may be why knuckleballs tend to be thrown slower than other pitches, the researchers suggest. While the fastest pitches can top 100 miles per hour, knuckleballs are usually closer to 60 or 70 miles per hour.

The scientists built a knuckleball machine, designed to launch a beach ball without any spin, and measured how much the ball veered off course. Then they calculated the ball’s expected motion based on the physics of the drag crisis and found that the predicted trajectories matched the experiments. The scientists’ calculations also correctly predict knuckleball-like phenomena in soccer, volleyball, cricket and baseball — but not in sports like tennis or basketball, where knuckleballs aren’t seen due to the properties of the ball, including texture, typical speed and how far it flies.

“It’s a fine piece of work,” says Alan Nathan of the University of Illinois at Urbana-Champaign, who studies the physics of baseball (SN: 3/23/13, p.32). But he is not entirely convinced by the explanation of knuckleballs. “Wind tunnel experiments seem to strongly suggest that it’s associated with the seams on the ball,” Nathan says, which can create turbulence that causes the ball to swerve.

So knuckleballs may remain as much of a challenge to explain as it is to hit them.
Citations
B.D. Texier et al. Physics of knuckleballs. New Journal of Physics. Vol. 18, July 13 2016, p. 073027. doi:10.1088/1367-2630/18/7/073027.
Further Reading
N. Seppa. Baseball’s resident physicist. Science News. Vol. 183, March 23, 2013, p. 32.

L. Sanders. Taming turbulence from afar. Science News. Vol. 178, July 31, 2010, p. 7.

https://www.sciencenews.org/article/scientists-throw-curve-knuckleb...

Ketone drink gives competitive cyclists a boost by altering their metabolism
A drink developed for soldiers to generate energy from ketones rather than carbs or fat allowed highly trained cyclists to add up to 400 meters of distance to their workouts, a UK-led study reports July 27 in Cell Metabolism. The supplement, which will be commercially available within the year, works by temporarily switching the primary source of cellular energy from glucose or fat to ketones -- molecules derived from fat that are known to be elevated in people consuming a low-carb, Atkins-like diet.

"It's really interesting; with a single drink of nutritional ketone you can do the same exercise with completely
different metabolism," says Dr. Pete Cox, a clinician at the University of Oxford and first author on the paper. "Given the findings of this study, which challenges our fundamental understanding of human physiology, it will be tempting for many to focus on pursuing the endurance and sport-related avenues, but it would be a great shame if the metabolic basis of this work was not further explored."

Ketosis is a way for humans to deal with starvation. Ketones are made in the liver from mobilized body fat, so when the body doesn't get enough fuel from food, internal fat stores are broken down to make ketones that feed the brain. Normal metabolism is driven by the burning of carbs and fat obtained in a balanced diet.

The idea to develop a ketone food group came from the Defense Advanced Research Projects Agency (DARPA), the research branch of the United States army, who put out a $10 million call for the development of the most efficient food for soldiers to take onto a battlefield. One of the people to answer this call was University of Oxford biochemist Professor Kieran Clarke. With Dr. Richard Veech at the National Institutes of Health, she assembled a team who invented the ketone ester drink, and this paper is the first efficacy study to show that the exogenous ketone can improve performance for certain types of activities. (Safety studies have already been conducted, and the drink does not have any adverse effects.)

In a study of 39 cyclists, including some former Olympians, they found that the muscles use ketones when provided in the diet, and that this uptake increases in proportion to the intensity of exercise. In one experiment, the researchers gave the cyclists "energy drinks," each infused with a different source of fuel -- carbohydrates, fats, or ketones -- and found that cyclists who had the ketone drink had the lowest levels of lactate, a byproduct of the body's breakdown of glucose, which is often associated with muscular stress, or the achy, tired feeling felt after a strenuous workout. The observation could help explain why the high-performing cyclists on the ketone drink traveled an average of 400 meters farther over a half hour than those consuming the carbohydrate or fat drink.

"The ketone itself is inhibiting glycolysis, so that with the same exercise you're preserving glycogen and producing much less lactic acid -- this hasn't been seen before," Clarke says. "What may be happening is if you are doing something that isn't a sprint, like going on a 26-mile run, you won't hit the wall as quickly. Not only that, but it stops you from aching afterwards."

While a good fit for marathon runners, the ketone drink is unlikely to help many Olympic athletes or sprinters, she says, because their exercise is primarily anaerobic, and the body needs oxygen to burn ketones. Clarke also cautions against drinking too much of the supplement, because while ketones become the primary metabolite, some glycolysis is also needed for them to have beneficial effects.

A University of Oxford spinout company, T?S® Ltd, will now develop and commercialize the ketone drink. Clarke says they are scaling up and are aiming to have the ketone food available for purchase by the end of the year. In the meantime, she and her group will continue to investigate the biology of this alternative metabolism in humans.
Nutritional Ketosis Alters Fuel Preference and Thereby Endurance Performance in Athletes. Cox et al. Cell Metabolism, 2016. DOI:10.1016/j.cmet.2016.07.010.

http://www.sciencedirect.com/science/article/pii/S1550413116303552

Science news source:
University of Oxford

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What Makes or Breaks Top Athletes

Will better training and coaching lead to new records, or do drugs and technology determine the score? Explore the science of the Games with these articles

http://www.scientificamerican.com/report/olympics-2016-what-makes-o...

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Magic Blood and Carbon-Fiber Legs at the Brave New Olympics

With technology and pharmaceuticals dominating our reality, how do we define “natural” human effort in sports? The author of bestseller The Sports Gene weighs in 

http://www.scientificamerican.com/article/magic-blood-and-carbon-fi...

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Scholarly Olympics: How the Games Have Shaped Research

A graphical guide to the impact of the Olympics on science

http://www.scientificamerican.com/article/scholarly-olympics-how-th...

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The science explaining how Usain Bolt became the fastest human in the world

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