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| Helmets for Kids in Winter Sports |
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| Snowmaking: Machines vs. Nature |
| Making Beautiful Ice |
| Ice Surfaces |
| Time-keeping and Photo Finishes: Seiko |
| Timekeeping and Photo Finishes: Lynx |
| How to Time a Ski Race |
| Olympic Web Site Stats Data Mining |
| Snow Crystals Are Beautiful for a Reason |
| Avalanches |
| Utah's Geology |
| The Environmental Effects of Biathlon |
| Nutrition Science and the Olympics |
| Olympic Physiology |
| Hypothermia and Frostbite |
| The Chemical Games |
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SPORT SCIENCE
Exploratorium: http://www.exploratorium.edu/hockey/skating1.html
Swartz: http://www.eskimo.com/~billb/miscon/ice.txt
Abstracts: http://www.skridsko.net/klubbar/data/science.html
Figure Skating, Jumping, and Rotating
To get a feel for just how difficult it is for a skater to do a quadruple jump, try it yourself. Don't even bother going for the gold. Just stand flat-footed, jump up in the air, and try to do one rotation. Can you land elegantly on one leg like the medallists on the ice? The smooth moves we see in skating and ski jumping are made possible only by long years of hard work. The fantastic feat of the quadruple jump needs practice and a thorough understanding of the biomechanics of the sport, but the jump doesn't stand on its own. Many factors enter into the flawless performances we witness at the Olympics and not the least of them is the physics involved in the application of the talent and training against the ice and wind.Biomechanics of Skating: http://btc.montana.edu/olympics/physbio/biomechanics/bio-intro.html
Jump Physics: http://alumni.engin.umich.edu/~gcoch/jumpphysics/jumpphys.html
Technical Figure Skating: http://www.northstarnet.org/eakhome/skating/kevinnew/
What racing strategy is most effective for speed skaters? This paper by Darren Dutto and Gerald Smith of the Biomechanics Laboratory at Oregon State University examined just that question. Dutto and Smith hypothesized that, in long endurance events like distance speed skating, "because of the relatively high speeds and substantial aerodynamic requirements, overall performance should in part be influenced by a skater's ability to maintain uniform speed throughout a race." The researchers then examined the results from the men's and women's 5000 meter events at the 1998 Winter Olympics and World Championships. They found that the winners of the women's events showed a consistent pacing strategy; although the winners did not necessarily demonstrate the highest maximum-lap speeds, they had a faster overall performance. However, the winners of the men's events were only moderately consistent in their pacing.
http://osu.orst.edu/hhp/exss/research/labs/BioMech/abstracts/temporal.html
The Science of Hockey provides an excellent and entertaining overview of many aspects of the fastest team sport on human legs. Divided into seven main sections - ice, skating, gear, saves, shooting, checking, and fitness - it's part of the sports science resources of the Exploratorium. First, we'd better explain the smug grin on this reviewer's face: the ice really is better in Canada. Just thought you should know. Sure, some say it's the climate but we're not going to go there. Did you know that colder ice is best for hockey and warmer ice for figure skating? Do you know why ice is slippery? We mean the real reason; none of those quaint notions about pressure or friction melting a thin layer of ice. Other questions answered here are how much time a goalie has to react to a slapshot, and how to test yourself to see if your reflexes are good enough for an NHL career. The San Jose Sharks players and team members feature prominently in the material here including QuickTime movies of players shooting and goalies making saves. This site scores.
http://www.exploratorium.edu/hockey/index.html
A gun has two distinct recoils? Author Sam Hokin describes "primary recoil" as "conserving" the gun-bullet system, that is, balancing the bullet momentum with an equal but opposite gun momentum. The secondary recoil, however, is the one most of us feel as the bullet leaves the muzzle of the gun and gases expand outward. These gases act like a rocket blast, forcing the gun backward against our shoulders. This would be the scene in the cartoon where the shooter is bounced backward on his can. To learn about recoil, bullet mass, and muzzle velocity, try the sites below. The latter two are edited by Glenn Elert from copy written by his students.
Recoil: http://www.bsharp.org/physics/stuff/recoil.html
Bullet mass: http://hypertextbook.com/facts/2000/ShantayArmstrong.shtml
Muzzle velocity: http://hypertextbook.com/facts/MariaPereyra.shtml
Hardly a surprise to anyone who has ever watched the event, every hundredth of a second is crucial in a bobsleigh race, the crew must face up to six G around some corners, and technology (and the money to afford it) now dominates the race. The crew must be in extraordinary shape, especially the brakeman whose role is critical and the most demanding. The Canadian Broadcasting Corporation (CBC) provides the details and excellent, fun visuals of the bobsleigh's design, crew, and actions. Included is an animated diagram of the track itself whose contortions are one of those have to be seen to be believed phenomena. The BBC site provides a personal experience piece with an amateur trying out the sport.
CBC details: http://www.cbc.ca/olympics/sports/bobsleigh/essentials
CBC visuals: http://www.cbc.ca/olygfx/swf/bobsleigh.html
BBC: http://www.bbc.co.uk/bristol/content/features/2001/11/22/bobsleigh_austria/bobsleigh_austria.shtml
Careening down a course feet first at 140 km/h, riding a luge is an exercise of controlled chaos. The rider's strength and quickness, especially at the start, certainly are factors, but the most critical element may be the team's expertise in designing, preparing, and tweaking the sled. The CBC again provides first-class pages that detail the ins and outs of luge competition and an entertaining animation about each step in the run, including the torturous track. There are physics to a luge run but they are pretty basic: friction, force, and gravity.
CBC details: http://www.cbc.ca/olympics/sports/luge/essentials
CBC visuals: http://www.cbc.ca/olygfx/swf/luge.html Physics of Luge: Physics of Luge:
http://www.pbs.org/ktca/newtons/9/luge.html
Luges are certainly built for speed and not for comfort. Traveling down a track on one's back just three inches from the ice sounds to us like a sure-fire recipe for an icicle enema, but this thrilling and dangerous sport has a beauty all its own. A cool and interactive tutorial from Montana State University-Bozeman presents the relation between luge and linear kinematics, linear dynamics, and the effects of Newton's Second Law. There are also pages on luge equipment, clothing, and tracks, as well as on street luge.
http://btc.montana.edu/olympics/physbio/physics/phys-intro.html
Between 80 centimeters and 120 centimeters long, and between eight centimeters and 20 centimeters high, the skeleton sled is a rocket on rails. A lead sprint of 40 meters that will last in the neighborhood of five seconds launches the athlete into a downhill slide. Two of these runs on the same day will produce a combined time, the lowest of which wins. Sounds simple, doesn't it? Well, recognize that the Utah Olympic Park track covers 1,340 meters and that's not in a straight line. Learn about the skeleton, check out a visual guide, and find out how the skeleton got its name by visiting the CBC. The Fastest Sledding site also has good data on human speed records for sled times.
CBC details: http://www.cbc.ca/olympics/sports/skeleton/essentials
CBC visuals: http://www.cbc.ca/olygfx/swf/skeleton.html
Fastest Sledding: http://hypertextbook.com/facts/2001/SharenChin.shtml
Apart from wondering about the talent you watch going downhill at crazy speeds during these Olympic Games, learning something about laws that act upon your skis is always useful, as they are the same laws acting on everything which moves in our world (and outside). This page will introduce you to concepts like kinetic and potential energy, friction, and gravity in a crescendo of laws (few numbers, guaranteed) bringing you to Newton's laws, that rule on any physical body moving in our universe. You'd never believe that a pair of skis would bring you to the moon, would you?
http://www.kent.k12.wa.us/staff/trobinso/physicspages/PhysOf1998A/Skiing-Jacobson/physics1.html
Cross-Country Skiing: The Biomechanics
Did you ever consider that cross-country skiing uses some of the techniques of ice skating? Oregon State University's College of Health and Human Performance maintains this site to inform about biomechanics research in a number of fields. Of course, with the Winter Olympics on our minds, we're particularly interested in the winter sports. A kinematic analysis of the 1992 Olympic Winter Games in Albertville, France provides information about the many skating techniques participants employed. Knee, hip, elbow, and trunk angles were analyzed, as well as strong and weak side motions of the knees. Double-poling, ski edging, and body alignment are also analyzed with an eye to effective techniques and why they are useful.http://osu.orst.edu/hhp/exss/research/labs/BioMech/BioMcDx1.html
Hurtling down a ramp at speeds in excess of 100 km/h and landing perfectly over 100 meters away is an act which seems to defy gravity, let alone sanity, but for ski jumpers it's all in a day's work. Indeed, "work" is the operative word at the Newton's Apple physics Web site. How do ski jumpers exploit the principles of physics to succeed? They try to convert all the gravitational potential energy they have at the top of the ramp to distance by adjusting their crouch during their in-run (reducing air resistance), leaping upwards and outwards at take-off, and by positioning their bodies and skis during flight to produce lift and reduce drag. This site covers all the scientific details of the sport and offers questions and activities for students. For the precise formulae of conversion of potential energy into kinetic energy, the animations-enhanced Physics Classroom utilizes the similarities between ski jumping and a roller coaster to demonstrate the Work-Energy Theorem, taking into account the mass and speed of your average ski jumper. Here one can also find links to other ski jumping sites.
Newton's Apple: http://www.mansfieldct.org/schools/mms/staff/hand/lawsskijump.htm
Physics Classroom: http://www.physicsclassroom.com/Class/energy/U5L2bb.html
Why Does a Curling Stone Curl?
Maybe it's not one of those pressing questions of the age, but you never know where curiosity will lead you. Dr. Mark Shegelski, Associate Professor of Physics at University of British Columbia and himself a curler, was curious why a rock thrown with a counter clockwise spin will curl to the left, especially as it slows down. Shegelski and some colleagues studied the question scientifically. The Canadian Curling News (CCN) gives us the gist of their findings. What's interesting is that an overturned glass subjected to the same kind of motion curls in the opposite direction. It's all ably explained and seems to make sense. Fortunately, when you're curling you don't need to think about it - just rely on the laws of physics to work. On the moon, however, it may be a different story. Becca, a high-school physics student to do Vermont proud, provides an amusing and calculating explanation of how to adapt curling for lunar competition, especially in terms of the size of the rink. Still, it's not clear whether a rock would curl on the moon or what effect super-low ice temperature would have on the game, which suggests the need for further study. Hello, NASA?CCN: http://icing.org/game/science/shegelsk.htm
Becca: http://www.muhs.acsu.k12.vt.us/physics/curling/changes.htm
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The Physics of Skiing: Skiing at the Triple Point
Faust's Gold: Inside the East German Doping Machine
Biomechanics in Sport: Performance Enhancement and Injury Prevention
Handbook of Sport Psychology
Physics of Ice
The Sporting Life (Accidental Scientist)EQUIPMENT/TRAINING
ACCS: http://www.xcskiworld.com/waxing/index.html
Glide waxing: http://www.sierranordic.com/Tech_tip_two.html
Waxing waxless skis: http://www.hamline.edu/~wnk/nordic-ski/2000/msg04114.html
One of the main reasons the Finnish army held off the Soviet Union during the Winter War of 1939-40 is the fact that the biathlon, a combination of skiing and shooting, is something like a national sport there. (The actual Finnish national sport is a 20th-century invention called pesapallo that resembles baseball.) Other combined athletic events are either complimentary or broken up; only biathlon combines exertion and the attendant rise in pulse and breathing with the need to relax and the need for muscle and breath control while target shooting. Cross-country skiing endurance is best improved either on the course or in the gym, but for the shooting aspect of the sport, high technology is there to help. An article in Photonics Spectra (December, 1997) discusses the use of lasers, infrared cameras, heart rate sensors, and video gear to help coaches and athletes improve shooting performance.
http://www.biathlon.net/phot_art.html
Marlin Jiranek, a research engineer at the Remington Arms Technical Center, shares his insights into the esoteric art of rifle barrel design in this PDF page (Adobe Acrobat or some other .pdf reader required) with a series of drawings, charts, and photographs that portray the problems the Remington designers faced when they tried to design a biathlon rifle barrel that was light but accurate, a seemingly intractable problem. The team eventually built a barrel with a steel inner liner and outer layers of composites (the exact compositions of which are secret). The page educates the reader in some of the basics of firearm barrel design, as well as the problems encountered in the use of composites for this purpose. It's not all barrels, though. After having trouble grouping his shots in very cold weather, and having ascertained that the problem was not in his sights, biathlete Allen Takahashi discovered that RWS ammunition burns more consistently at lower temperatures, albeit with a lower muzzle velocity, thereby improving his accuracy in cold conditions.
Biathlon Jiranek: http://www.dtic.mil/ndia/infantry/jiranek.pdf
Takahashi: http://www.biathlon.net/low_temp.html
Helmets for Kids in Winter Sports
Some of the brightest colors you'll see at the Winter Olympics will be on the helmets of skiers and snowboarders. Participants in competitive alpine ski racing, snow boarding, and hockey are required to wear helmets, but there's no such requirement for participants in recreational winter activities like skiing and snowboarding. Should helmets be required for recreational winter sports? In 1997, the American Medical Association (AMA) investigated this question and found two problems with issuing such a requirement: one, there are no current standards for the manufacture of helmets or data on their effectiveness; two, there's no in-depth data on the frequency of skiing and snowboarding injuries among children and adolescents. The AMA called for further research into both of these areas but, in the meantime, urges children and adolescents to wear helmets anyway.http://www.ama-assn.org/ama/pub/article/2036-2441.html
Jack Frost always manages to get a ticket to the Winter Olympics and science has developed fabrics to keep both athletes and spectators warm. Polartec is a family of more than 150 fabrics designed for comfort in all kinds of weather. The story of Polartec began in the 1970s, when the owner of Malden Mills in Lawrence, Mass. asked his research and development team to develop a synthetic alternative to wool. Malden Mills introduced the new fabric, originally called Polarfleece, in 1991. Since then, the company has reduced the synthetic fabric's tendency to pill, has introduced fabrics of various weights, and has developed water-repellent variants. Between the athletes and their fans, you'll probably see a lot of Polartec at Salt Lake City.
http://www.maldenmills.com/02_polartec/02_02_fabrics/index.html
FACILITIES AND OPERATIONS
Snowmaking: Machines vs. Nature
Skiing was once an unpredictable adventure not only because of the chance of accidents, but because you never knew if there would be enough snow for good skiing when you arrived. Snow made by machines may seem offensive to the pure at heart but the technology has certainly saved a weekend getaway or two. And snow is snow, minute crystals of frozen water, whether made by nature or pumped by machine - almost. The process is complicated and these three sites cover the problems of wet vs. dry snow, the use of computers, the challenge to keep a resort's snow just right, and environmental issues. The first two sites listed below are informed commercials from snowmaking companies. The third is a non-partisan article from First Tracks magazine. The article avoids the promotional atmosphere of the commercial sites, but the American Skiing Company site is the most comprehensive.American Skiing Company: http://chat.peaks.com/snowmake.html
Ratnik: http://www.ratnik.com/snowmaking.html
First Tracks: http://www.firsttracksonline.com/snowmaking.htm
Every skating enthusiast has seen those wonderful vehicles, crosses between a grader and a garbage truck, that circle rinks between events. Those in the know always call these machines, no matter what make or model, "Zambonis". It's like calling any kind of tissue a Kleenex. The real Zamboni site tells the amusing, "triumph of American ingenuity" tale of Zamboni's development of these machines in the 1940s - in California of all places. A second Zamboni page has a simple diagram of how these machines work. Jet Ice's commercial site describes the paints and stencils used to put lines and designs on ice. The company makes semi-transparent ice paint ideal for ice shows and special events, black light ice paint, and jet gloss designs that are part of the modern ice making repertoire.
Zamboni tale: http://www.zamboni.com/story/story.html
Zamboni diagram: http://www.zamboni.com/trivia/how.html
Jet Ice: http://www.jetice.com/products.html
For a skater, curler, or hockey player, the quality of the ice on the rink is critical. Water is not simply poured on and frozen. For the best ice, the water has to be applied layer by layer, each often as thin as 1/32 of an inch. The water freezes because the temperature of concrete floor underneath has been brought below freezing by a maze of underground refrigeration pipes. Operators have to adjust the freezing process to take into account the ever-changing effects of the outdoor temperature and humidity. The ice has to be painted, whether just white to improve the reflection or covered with the logos and markings needed for games. This is a good site to bookmark for the future, filled as it is with wonderful information on how things work.
http://www.howstuffworks.com/ice-rink.htm
Time-keeping and Photo Finishes: Seiko
When hundredths of a second can mean the difference between winning a medal and going home empty-handed, the timing system had better be accurate and reliable. The Seiko for Winter Sports site presents the color-slit video camera that replaced the photo-finish camera in 1991, and which is used for short-track speed skating. You can also learn about new video equipment designed to increase the accuracy of ski jumping judges, who measure distances visually. There are also detailed explanations of the equipment used for timed events such as alpine skiing, speed skating, bobsleigh, and luge. Reliability is just as important - Seiko even explains the workings of the equipment that monitors the time-keeping equipment. In sports such as figure skating that don't require split-second accuracy, Seiko equipment measures the elapsed time of a competitor's program, then immediately records and posts the scores submitted by the judges. The Seiko for Other Sports Web site describes equipment used in track and field events and provides information useful for athletes in developing better start strategies.Winter Sports: http://www.seiko.co.jp/english/news_events/sports_timing/winter_sports/index.html
Other Sports: http://www.seiko.co.jp/english/news_events/sports_timing/sports_timing.html
Timekeeping and Photo Finishes: Lynx
Another player in the area of data collection, organization, and distribution at the Winter Olympics is Lynx System Developers, maker of software and hardware products. Speed Skating: Overview describes how Lynx's digital cameras with low-light sensitivity produce images that allow judges to determine with confidence which competitor crossed the finish line first. The company also supplies software that lets race data be displayed immediately in formats compatible with scoreboards and broadcast television. Speed Skating: Solutions explains the various packages of equipment (hardware and software) the company offers for various levels of timing in speed skating events, from a monochrome entry-level system up to an international competition two-camera system.Overview: http://www.finishlynx.com/sports/skating/overview.htm
Solutions: http://www.finishlynx.com/sports/skating/solutions.htm
The New York State Ski Racing Association's (NYSSRA) educational Web page presents its guidebook on timing and calculation as a primer for those who help time ski races. It's not necessary to read the guidebook straight through chapter by chapter, the page informs us - which is a good thing, because much of the material is detailed and technical. Even a casual reader will probably enjoy chapter three, "A Brief History of Timing". Back at the dawn of ski racing, the only competitive event was what we now know as downhill. Originally, all skiers went down the same course at the same time, and the first one to cross the finish line was the winner. This race format soon led to less than friendly competition as the racers all tried to nudge each other off the course (a format later celebrated in short-track speedskating) and so the staggered start was born, and along with it the necessity of timing each competitor's race. The chapter goes on to explain, with colorful diagrams, the electronic timing systems in use today that make results and rankings available immediately.
http://home.eznet.net/~vraguso/Book_4.html
Olympic Web Site Stats Data Mining
Long after the last national anthem was played at the Nagano Winter Olympics, the data tracings of countless Web visitors are still providing insights that will guide the development of future Web sites. Wired's brief overview highlights the challenges IBM faces in trying to extract nuggets of useful information from the terabyte of data it obtained. What did site visitors look at? How deep did they go? What sort of navigation patterns did they trace? These and hosts of other questions can produce surprises that illustrate why such data mining is useful. One puzzle they'd like to answer is why more visitors to the Japanese language Nagano site went beyond the start page than did visitors to the English site. There aren't any gold medals given for all this work - just vital clues about how to satisfy information needs better.http://www.wired.com/news/print/0,1294,14175,00.html
GEOGRAPHY/GEOLOGY/WEATHER
Snow Crystals Are Beautiful for a Reason
Softly floating down to your tongue, snowflakes enchant us as children and continue to amaze us as adults. Science has intensely studied snow crystals, from hollow columns to stellar dendrites. Edited by Kenneth Libbrecht of Cal Tech, this site offers a snow crystal primer, a FAQ on snowflakes, and lots of information on snow crystal physics. Not content to study natural snowflakes, Libbrecht and his colleagues grow their own designer crystals to better understand how they form.http://www.its.caltech.edu/~atomic/snowcrystals/
How fast do avalanches travel? What causes them? How dangerous are they and can they be predicted? All these and many more of the avalanche-related questions that have you lying awake at night can be answered at this informative site brought to you by the now Olympics-relevant Utah Avalanche Forecast Center (UAFC). Hopefully, avalanches won't be a feature of the Winter Games, although they have to be kept in mind. The Web site is an extremely practical guide for skiers, snowboarders, hikers, and other winter mountain types. It helps them judge avalanche dangers and teaches what to do if caught up in one. Did you know that 35% of all avalanche fatalities from 1993-1998 were snowmobilers? A more in-depth examination of the formation and dynamics of avalanches, based on years of research and observation (primarily by the Swiss) is to be found in a March 2001 article from Physics World. The author shows how known environmental variants have allowed a statistical model to be created and used as an avalanche warning system.
UAFC: http://www.avalanche.org/~aaap/questions.HTML
Physics World: http://physicsweb.org/article/world/14/3/7
Right about now, you might be wondering about the spectacular geology of Utah and perhaps even its geologic history. That's the sort of people we NSS types are, isn't it? The Utah Geological Survey (UGS) comes to our rescue with its brief and to the point overview. It lets you step through the ages from Paleozoic through Jurassic, Cretaceous, Paleocene, Eocene, with small maps and brief text that explains the geological situation of the time. This stuff is always great fun for folks who think that any environmental change is bad. The methane-breathing denizens of early Earth would certainly have agreed, even as they sensed first whiffs of that poisonous oxygen. To complement this, the State of Utah provides an engaging geological panorama of the state's "diverse, spectacular, and dynamic" geology in a text aimed at intelligent non-geologists. It conveys how intriguing and useful it is to visit an interesting location and think and learn about how that place came to be, and the forces that molded and continue to act on it.
UGS: http://www.ugs.state.ut.us/utahgeo/geo/geohistory.htm
State site: http://www.utahhistorytogo.org/geology.html
The Environmental Effects of Biathlon
In a word: bad. Then again, you could easily say the same about any winter sport. We have to cut down trees to create the trails in forests, use gas-guzzling snowmobiles and grooming machines to pack the trails, spray lead bullets around (a biathlete competing at international levels fires some 8,000-9,000 rounds per season), use ski waxes with fluor-carbons, and, of course, drive our cars to get to the meets. On the other hand, biathlon facilities are saved from development, and it's possible that some time in the future biathletes will use rifles that fire a laser beam instead of bullets. Dave Main's Biathlon Page has the details.http://www.sd83.bc.ca/stu/9806/dpmf-environment.html
OLYMPIC MEDICINE
Nutrition Science and the Olympics
Because Olympic athletes know the truth of the bromide "you are what you eat", their training includes not only physical conditioning but also strict attention to diet. Patti Steinmuller, an adjunct instructor in food and nutrition from the Department of Health and Human Development at Montana State University-Bozeman, has developed a three-credit online graduate course on the relationship between nutrition and peak athletic performance. Using short videos, animated diagrams, and question-and-answer summaries, the course teaches how muscles work, how the body stores and uses energy, how the intensity and duration of training are related to energy stores, and how nutrition and fluid balance affect athletic performance. The information focuses on winter sports (ice hockey, cross-country skiing, and figure skating) but can be applied to other sports. There's also a section about the feeding of athletes at the 1996 Summer Olympics in Atlanta and an extensive list of books, videos, and Web sites about nutrition and fitness.http://btc.montana.edu/olympics/nutrition/default.htm
Ever assisted at a cross-country ski race? If you have, you've surely admired those athletes skiing up and down for up to 50 kilometers and wondered how they could race for so long in the cold, and still be... alive. This site, which organizes coursework for cross-country skiing physiology, can help you understand the physiological changes in heart, muscle, and body during these types of exercises. For every assignment, an introductory explanation of the relevant physiology explains how the body copes - better knowledge of our body helps us not to abuse it.
http://btc.montana.edu/olympics/physiology/default.htm
Cold, very cold, can be a bad beast when you have to face it. Hypothermia and frostbite are both consequences of cold, but with different localizations. While frostbite is freezing of a part of the body, usually an extremity, hypothermia can be more life-threatening, as it causes a systemic fall of temperature - and the heart stops beating at approximately 29-30 degrees C. Three sites bring you more information. The Search and Rescue Society of British Columbia (SARBC) has a link-filled Web page devoted to all aspects of hypothermia, Hypothermia.org concentrates on treatment, and the Treatment Technology site has various high-tech medical equipment used in treating the condition.
SARBC: http://www.sarbc.org/hypo.html
Hypothermia.org: http://www.hypothermia.org/
Treatment Technology: http://www.hypothermia-ca.com/
PERFORMANCE ENHANCEMENTS
http://www.sciam.com/specialissues/0900sports/0900zorpette.html
Doping in sports is somewhat like an arms race. As soon as I have a new drug, you develop a new method to detect it, then I produce a new drug, and you a new method to detect, then I... and so on, in an endless loop. Putting aside ideals and recognizing that doped athletes exist, it's a good idea to learn more. Sites from the World Anti-Doping Agency (WADA) and the Olympic Studies Centre (OSC) offer much information, in the form of documents, FAQs, and links to other sites. The International Olympic Committee (IOC) obviously has views on the matter, and also lists prohibited substances and explains detection strategies. Last May's International Symposium on Technological Innovations in Laboratory Hematology included a technical workshop on blood doping and detection. What else is there to say? Try WADA's motto: "Think positive, test negative."
WADA: http://www.wada-ama.org/asiakas/003/wada_english.nsf/
OSC: http://blues.uab.es/olympic.studies/dir/dso.html
IOC: http://www.olympic.org/uk/organisation/commissions/medical/antidoping_uk.asp
Workshop: http://mmserver.cjp.com/gems/labhem/7.1.Doping.pdf
This site presents blood doping from a different perspective, that of the hard-core performance athlete who is willing to use drugs and doping to improve performance. This specific page concentrates on methods to increase the hematocrit, the relative volume of erythrocites (also called red blood cells, the cells that transport oxygen) in our blood. The paper also discusses some of the reasons why levels of blood oxygen could vary due to natural causes, such as high altitude workouts or heavy perspiration. It concludes with a cautionary note presumably aimed at those who test positive for blood doping: "The legal implications following a positive result... do not allow approximation; each method should be carefully considered and clinically validated as it must unequivocally represent a definitive proof of transgression or pathology."
http://www.sportsdoping.com/sportsdoping/methods.html
This article in the Encyclopedia of Sports Medicine and Science perhaps raises more questions than it answers. Anabolic steroids, essentially testosterone or derivatives, are widely used in sports - just how widely isn't known for obvious reasons - to improve muscle mass, strength, aggressiveness, and endurance. These compounds stimulate receptors in muscle cells which then trigger increased protein production and decreased enzymatic protein degradation. Despite the notoriety and popularity of anabolic steroids, there seems to be some doubt about their effectiveness. Do they really boost athletic performance through biochemical means or are they essentially just placebos that benefit users largely through psychological influences? Controlled studies seem to suggest that benefits are actually quite minor, whereas anecdotal evidence from trained athletes suggests they are powerfully enhancing. There's little doubt, though, that when athletes stop taking steroids, they face major psychological problems as size and strength decrease rapidly, and that there are long-term health risks from their use.
http://www.sportsci.org/encyc/anabster/anabster.html