Let’s talk about your best piece of coaching advice…either advice you were given or advice you gave to another coach or wrestler (heck it does not even have to be wrestling related – coaching is coaching).

If we get at least 10 responses, we will give away a WrestlingGear.Com t-shirt to someone randomly that posts a response. We will select a winner in about a week…

Nutrition, and Weight Control
By Dan Gable
Buy Coaching Wrestling Successfully

Nutrition and weight control are probably the most controversial subjects in wrestling. Of course, the key issue here is weight loss. The image of a dehydrated wrestler wearing a sweatsuit in a hot gym in order to lose weight is not a healthy one for the sport. What wrestling needs to promote in terms of nutrition and weight is fitness and health.

Rules on Weight Control

Following the lead of the National Collegiate Athletic Association, the National Federation of State High School Associations has tightened regulations on weight control in wrestling. The NCAA made eight rule revisions after the deaths of three college wrestlers during weight-loss workouts.

All state associations are now required to develop and use a weight-loss program that discourages severe weight reduction. Each wrestler is also required to establish a certified minimum weight before January 15. Certification at a lower weight is then prohibited during the season. Another rule requires wrestlers to have at least half of their weigh-ins during the season at the minimum weight to be used during the state tournament.

Education is the key here. Athletes and coaches need to understand the importance of proper nutrition and end the training practices that brought about the association of starvation with wrestling. School systems should require nutrition courses. In addition, coaches, especially wrestling coaches, should have classroom-type discussions with their athletes about healthy eating and adequate fluid intake.

One key to success is being able to get quality work and effort out of your team on a consistent basis. Without proper nutrition, wrestlers’ attentiveness and stamina will fall off drastically, especially late in practice. I constantly read my athletes to gauge when to do a certain workout or conditioning drill and for how long. The more I can keep them working with quality efforts and attentiveness the better they are going to get.

Water availability along with an electrolyte (sports) drink is a must. The drinks should be cold for incentive to drink as well as for recuperation purposes. Disposable cups should be used and not shared. If your water source is a drinking fountain, make sure the water is cold and easily drinkable. Oftentimes in older facilities drinking fountains are nearby but barely working. Keep them usable and clean. Drinking fountains are not for spitting, blowing one’s nose, or getting rid of gum or chewing tobacco (which should not be permitted, anyway). Keep tissue and plenty of garbage cans for trash handy.

Coaches should have their athletes’ body compositions tested and have all the needed data and calculations for each athlete. The maximum weight loss under normal conditions should be no more than two pounds per week. Within this range, wrestlers should be able to maintain their strength and keep a positive attitude. Don’t let the athletes just tell you what they weigh; weight checks are necessary. Keep your eyes open for signs of incorrect weight loss measures or weight loss that is too rapid. Clear warning signs are lack of sweat, jumpy attitude, poorer performance, noticeable changes of body size, and frequent trips to the bathroom.

Because of recent tragedies in the sport involving wrestlers and weight loss, extra emphasis is being placed on education and safety rules. Specific concerns about the role of supplements and possible prescription drugs while training intensely are being looked at as well.

At the University of Iowa we test the body fat composition of our wrestling team once a year, and then periodically check some wrestlers throughout the remainder of the year. Each year in early to mid-September the team has mandatory testing with the team athletic trainer. This is within a month after they have returned to school and right around the start of organized practices. The results are used as a guide for the coaches and medical staff to evaluate the roster and begin making decisions about who will wrestle in which weight class. It also allows enough time to counsel and guide the wrestlers on how to safely and properly lose any extra weight over the next eight to ten weeks leading up to their first competition, which is usually in late November. New weight procedures could make for a possible date change of early testing.

The testing method we use at Iowa is caliperThe testing method we use at Iowa is caliper measurement. We have access to underwater weighing equipment, which is supposedly the most accurate measurement of body fat, but we use the calipers for several reasons. First, it is less time consuming for both the athletic trainer and the athlete. Second, calipers are more readily available and the test is easier to perform. Finally, underwater weighing has a high learning curve for those being assessed. If the testee is not well trained in having this done, the results may vary dramatically.

We test six different sites on the body with the calipers and use a formula developed by exercise physiologists which is specific to male high school wrestlers. Although these are collegiate wrestlers we are testing, the difference is believed to be minimal. The six sites we measure are the scapula, triceps, chest, suprailiac (hip), abdomen, and thigh. (See the worksheet at right)

We also measure their body weight and use the body fat percentage to estimate the “ideal” weight of the wrestler. The ideal weight is theoretically what the wrestler would weigh if they dropped their fat percentage down to five percent fat, which is the figure recommended for college-age athletes not to drop below. For high school athletes, it is recommended that they not drop below seven percent body fat.

In an attempt to be consistent among team members and from one reading to the next on the same athlete, we have an experienced technician perform the tests on all the athletes each time. In our case, the team athletic trainer performs all of the testing.

We recommend that the athletes be tested in the morning hours before they have eaten or worked out. It is important that they are well hydrated since a dehydrated state can skew skinfold readings. This is also when a most accurate weight can be assessed. It is possible and highly likely that with new procedures for making weight, hydration testing will be used along with skinfold measurement.

Attitude

Proper attitude is the last but certainly not the least ingredient for wrestling success. This trait affects all other areas. Without the proper attitude, a wrestler will only go so far. Physical ability can make a wrestler a winner early on in his career, but at more advanced levels where the difference in talent narrows, talent alone won’t do it. Your athletes have to be motivated to a very high level for them to be champion wrestlers. Their competitive abilities must be brought out of them through an internal desire to excel and maximize their abilities.

Through observation and good communication you can tell which athletes need to work on their attitude. Through team and individual discussions, you can bring about big improvements. Even highly motivated wrestlers need personal attention, so don’t overlook anyone on the team. You can address attitude in many ways, but it starts at the top, so make sure you (the coach) represent what you want your wrestlers to accomplish.

Next issue: Practice – Part 5

ABOUT THE AUTHOR

Dan Gable stands as one of the United States’ greatest collegiate and Olympic champions. As head wrestling coach at the University of Iowa from 1977 to 1997, Gable won the Big 10 Conference Championship in each of his 21 seasons. He also won an unprecedented 15 NCAA Wrestling Championships, including nine straight from 1978 to 1986.

As coach of the 1984 Olympic wrestling team, Gable led the United States to seven gold medals and two silvers and was named “best coach.” An Olympic wrestler himself in 1972, Gable dominated the field, going unscored upon in six matches to take the gold. Now serving as assistant to the athletic director at the University of Iowa, Gable has been inducted into both the Olympic Hall of Fame and the National Wrestling Hall of Fame, and in 1996 he was listed as one of the top 100 U.S. Olympians of all time.

From Coaching Wrestling Successfully by Dan Gable, Copyright 1998 by Dan Gable. Excerpted by permission of Human Kinetics, Champaign, IL.

By Ray Nunamaker

Assuming your wrestling program is well established in your school and your community, you’ll be anxious to make the leap to greater recognition, possibly at the national level. Much of what is required for that is some years of consistent, successful results from your teams. This requires tremendous perseverance and dedication. Where do you start?

Do What’s Right for the Wrestlers

The Wrestling Room.

Have a permanent room that is at least large enough for one full mat (42’ x 42’). If you can get more space, take it. Keep the room clean and orderly. Create specific places for jump ropes, time clocks, score flip-cards, announcements, newspaper articles, running shoes, extra clothing, etc. These items should not become safety hazards by being scattered around the room. Make sure you have sufficient heat in the room to avoid injuries and to allow the kids to get a good workout. Everyone should take pride in the room.

Summer Wrestling.

The Nazareth Recreation Commission always sponsors a summer wrestling program. It is basically an open wrestling room 2 or 3 nights a week, where there is no regimen of formal instruction. It gives wrestlers a place to work out, and often also attracts former wrestlers who are now in college. It’s a nice informal atmosphere where boys can focus on weak areas in their style yet have no pressure. The room should be supervised by a responsible adult at all times.

Summer Wrestling Camps.

Encourage wrestlers to attend a technique camp or team camp in the summer. About seven years ago we moved to a team camp. It’s great for camaraderie. Some camps also allow you to bring your junior high team. This is a good way to expose the younger wrestlers to their future coaches and teammates.

Out of Season Tournaments.

If your wrestlers participate in other sports, that’s great. If they don’t, and they are interested in competing in open tournaments off season, encourage them to do so. This may mean taking them yourself and spending long hours in the gym, but it provides necessary support for them, and helps them develop their skills more quickly. Out of season tournaments should not be required, because if the boys don’t really want to do it, they won’t really benefit, and everyone is just wasting time.

Match Atmosphere.

Play music during your team’s warm-up, between the JV and Varsity matches, and during time-outs. There are some great songs that will pump-up the crowd and keep everyone enthused, including the current Jock Jam series. Allow the team to pick the music, but maintain final veto power.

Junior High Matches.

When schedules can be arranged, have your junior high team wrestle at the same time as your JV Team, prior to the Varsity match. Put two mats out and let them compete right next to each other. It’s great for the junior high to wrestle before a crowd and get some recognition, plus it brings more fans to the gym. It also means there is rarely a dull moment, since something exciting is probably happening on one mat or the other.

Build Tradition

Wrestling Yearbook.

Find someone who’s interested and likes math, and start compiling all sorts of statistics. Do research, and get as much historic data as possible, then keep things current each year. At the end of the season give each wrestler a book containing highlights and stats from the season, plus some history of your school’s program with records (team and individual). Our yearbook also includes photocopies of significant newspaper articles and box scores from the season.

Wall of Fame.

Devote one wall in your wrestling room to display a photographic history of the boys who achieved a specific level of success on your teams. Determine the minimum requirements, and hang an 8 x 10 photo of everyone who meets them. Include their name, years, record, and accomplishments. Every day the current members of the team have only to look as far as that wall for inspiration. Every wrestlers’ goal should be to make “the wall”.

Wrestling Records.

Select another wall in your wrestling room to prominently display all of your school’s wrestling records, team and individual. These records should include things like career wins, most season wins, most falls, most technical falls, most takedowns, etc. Let your team know what’s possible, and also that records are made to be broken. For major accomplishments such as State Champion, hang banners in your gymnasium for everyone at every athletic event held in the gym to see.

Foster an Interest in College Wrestling

Attend College Matches.

Take your entire team to a local college match of the highest quality available. Our team goes to a Lehigh University match together each year. Call ahead to find out if you can get a group rate or reduced admission fee. Watching college wrestling provides the boys with a glimpse of what they can expect at the next level.

Open for a College Match.

Wrestling before a college crowd provides your team with an opportunity to promote itself to a new and often very responsive audience. Fans of college wrestling are able to see the type of program you have, and the caliber of kids who compete for you. This year Nazareth’s team had the unique opportunity of opening their season in a twin under-card at Hershey Park Arena with Lock Haven and Nebraska as the feature event. This is exciting for your team, their parents, and all of your fans.

Host a College Match.

Nazareth was fortunate to be able to arrange a dual meet between North Carolina State and Wisconsin at their high school gym a few years ago. Both teams were at nearby Lehigh for the Sheridan Wrestling Tournament, and agreed to come to town one day early for this match. There were four local young men wrestling for the two Division I teams that night, which sold out the gym. The fans really enjoyed seeing top college wrestling so nearby.

Get Connected.

Over the years you will probably meet and get to know many coaches at all levels. Use your connections to help boys have the opportunity to attend college and wrestle. Write letters and promote your kids. Help them be realistic about the schools they consider, because obviously academics are the real deciding factor. You can provide valuable guidance beyond what they can get from the school’s counselors. Do whatever you can for the kids; they will be grateful.

Article provided by Wrestling USA Magazine (www.wrestlingusa.com) for exclusive use by WrestlingGear.Com

When a new parent comes into our store they have the benefit of talking to our staff. If you wind up talking to me, I have over 25 years in the sport either as a coach, wrestler or fan. When I wrestled I always had a hand me down head gear so you don’t need to buy a new head gear right away.

But now a days, I can tell you if you spend a little more on a head gear you get more comfort. And with more comfort and generally the ability to hear your coaches better (both in practice and in a match), you will find your son or daughter will wear their head gear more often. If you take a look at my ears, you would not know that I wrestled. I am happy now as an adult that I did wear my headgear as a young wrestler.

Another thing to consider is your wrestler will not grow out of an adult head gear and will take a few years normally to grow out of a youth one. So if you are going to spend money on gear in only one place, spend the extra $15 to upgrade your first choice of the cheapest headgear into one of the best headgears out there.

Now if your wrestler likes a cheaper one or you just can’t swing a more expensive one, all of them available at our website are great and will do the trick. Just like shoes, often times wrestlers buy a headgear based on how cool it looks or that no one else has that particular headgear.

Now that you know, start shopping for your wrestling headgear.

What are your thoughts about this program?

Here is a link to check out along with several others you should click on if you are interested. Click on Active Start, Fundamentals, Learn to Train, Train to Train and Active for Life.

http://www.canadiansportforlife.ca/default.aspx?PageID=1004&LangID=en

I think it’s a great model – have you found anything like this based in the USA?

Below is the content from the Active Start Section – I think it’s worth checking out if you are a coach or a parent interested in your kids performance on and off the field. I know with my kids we have taken this relaxed approach to their athletic development. We want them to participate in high school and collegiate athletics if they are interested (e.g. I don’t want to burn them out on tee ball or youth wrestling!).

Active Start
Ages 0 – 6

From ages 0-6 years, children need to be introduced to relatively unstructured play that incorporates a variety of body movements. An early active start enhances development of brain function, coordination, social skills, gross motor skills, emotions, leadership, and imagination. It also helps children build confidence, develop posture and balance, build strong bones and muscles, promote healthy weight, reduce stress, improve sleep, learn to move skillfully, and learn to enjoy being active.

Objectives: Learn fundamental movements and link them together into play.

Physical activity is essential for healthy child development during the critical first six years of life, and is especially important during the first three years since brain growth is extremely rapid, and learning creates more brain cell connections than in later years (Gruhn, 2002). Among its other benefits, physical activity during this time:

* Lays the foundation for future success in skill development, by helping children enjoy being active, learning to move efficiently, and improving coordination and balance.
* Creates neural connections across multiple pathways in the brain (Council of Physical Education for Children, 2000) particularly when rhythmic activities are used.
* Enhances development of brain function, coordination, social skills, gross motor skills, emotional development, leadership and imagination. Helps children to build confidence and develop positive self-esteem.
* Helps builds strong bones and muscles, improves flexibility, develops good posture, improves fitness, promotes a health body weight, reduces stress and improves sleep.

Things to think about:

At this age, physical activity should always be fun, and part of the child’s daily life, not something they are required to do. Active play in a safe and challenging environment is the best way to keep children physically active.

Organized physical activity and active play are particularly important for the healthy development of children with a disability if they are to acquire habits of lifelong activity. Because this is a period when children with a disability rapidly outgrow their mobility aids, communities need to find effective ways – for example, equipment swaps or rentals– to ensure that all children have access to the equipment they need to be active.

Children with sensory disabilities (visual impairment or hearing loss) often require more repetitions to learn movement skills, and different ways of getting information from the instructor. To find out more, contact your local organization providing support for persons with the specific disability.

Physical Literacy Activities

Encourage the child to run – not just in a straight line, but with stops and starts and changes in direction. Tag and chasing games are excellent.

Play catching games with the child. Use a wide range of soft objects, and balls of different sizes. Start with catching a large ball with two hands, and progress towards smaller balls and eventually one handed catching. Remember – Balls that don’t bounce too much are great for learning, as are bean-bags.

* Play games making body shapes – upside down and right-side up. Pretend to slither like a snake, and roll like a rolling pin on the floor, or down a small grassy slope.
* Play throwing games – and start with soft objects that the child can hold easily in his or her hand. Try to get the child to throw at a target, and sometime to throw as hard as they can. Get them to use both the left and right hand when they throw.
* For quiet times, or when in small spaces, play balancing games. Stand on one foot and then try the other – try balancing on different body parts, and try walking along any painted lines on the ground.
* Jump, make shapes in the air, jump to see how high the child can go, or how far. Make imaginary “rivers” and get the child to jump from one bank to the other. Try jumping from one foot, or from both. Make sure the child bends at the knees when they land.
* Introduce children to water activities and learn to swim programs. Get them on skates or skis and out on the ice or snow so that they learn to slide.
* Ride a tricycle, or a bike – with or without training wheels to develop dynamic balance.

David R. Lamb, Ph.D.
Exercise Physiology Laboratory
Sport and Exercise Science Faculty
The Ohio State University
Columbus, OH
Chairman, Gatorade Sports Science Institute

KEY POINTS

1. For most sports, the top competitor is generally the one who can appropriately sustain the greatest power output to overcome resistance or drag.

2. It is not sufficient for championship performance to simply have the ability to produce great power. The champion must be able to sustain power output in an efficient and skillful manner for the duration of the competition.

3. During maximal exercise lasting a few seconds, the anaerobic breakdown of phosphocreatine and glycogen in muscles can provide energy at rates many times greater than can be supplied by the aerobic breakdown of carbohydrate and fat. However, this high rate of anaerobic energy production cannot be sustained for more than about 20 seconds.

4. For exercise lasting more than a few minutes, an athlete who has a high lactate threshold, that is, one who can produce a large amount of energy aerobically without a major accumulation of lactic acid in the blood, will be better able to sustain a higher rate of energy expenditure than will a competitor who has a lower lactate threshold.

5. A high level of mechanical efficiency, which is the ratio of the mechanical power output to the total energy expended to produce that power, is vital if an athlete is to make the most of his or her sustainable rate of energy expenditure. Mechanical efficiency depends upon the extent to which the athlete can recruit slow-twitch muscle fibers, which are more efficient at converting chemical energy into muscle contraction than are fast-twitch fibers.

6. Neuromuscular skill is also critical to mechanical efficiency because the more skillful athlete will activate only those muscle fibers required to produce the appropriate movements. Extraneous muscle contractions require more energy expenditure but do not contribute to effective power output.

INTRODUCTION

The criterion for success in many sports, including those involving running, swimming, bicycling, speed skating, rowing, and cross-country skiing, is simply the time required to propel the athlete’s body (and essential equipment such as a bicycle, rowing shell, or skis) for a given distance. In the case of Olympic weightlifting and power lifting, success is determined by how much weight can be lifted in the appropriate movements, whereas a wrestler is judged by the degree of physical control over the opponent. These sports are quite different in terms of the patterns of muscle recruitment, the force and power produced, and the equipment used; nevertheless, success in all of these seemingly diverse sports depends on a complicated application of a simple principle–the champion is the athlete best able to reduce the resistance or drag that must be overcome in competition and best able to sustain an efficient power output to overcome that resistance or drag (Figure 1)(Coyle et al., 1994). This review provides an analysis of the major factors that contribute to an athlete’s ability to produce power appropriately to overcome resistance or drag and a number of important applied principles designed to help trainers, coaches, physiologists, and others assist athletes in achieving their goals in sport.

Figure 1. mode; of the interrelationship of major factors determining sport performance. Performance is determined by how effectively the athlete can sustain sufficient power output to overcome various types of resistance or drag, depending on the sport event. Sustainable power output depends on the rate of energy expenditure that can be sustained throughout the event and the efficiency with which that energy can be converted into mechanical power. Depending on the sport event, sustainable energy expenditure will be a function of the ability to sustain the production of energy by anaerobic and/or aerobic means. Mechanical efficiency is dependent on muscle efficiency, i.e., the efficiency with which muscles convert the energy stored in carbohydrate and fat into muscle shortening, and the neuromuscular skill with which the athlete performs the event, i.e., the degree to which the athlete has learned to recruit only those motor units required to produce maximal power output in a skillful way.

RESISTANCE AND DRAG: EXAMPLES IN SPORT

Examples of resistance in sport include the mass of a barbell in Olympic lifting or power lifting, the muscular efforts of an opponent in wrestling or judo that are used to offset the movements of a competitor, and the effect of gravity on resisting a marathon runner’s ability to move up a hill. A lifter who can sustain adequate power output long enough to correctly lift a greater weight than a competitor will beat that competitor. Likewise, a competitor in wrestling or judo who can sustain power sufficient to overcome the resistance provided by the opponent throughout the match will be the winner.

Drag is a special case of resistance in which the friction of air or water around a competitor retards forward motion. Obvious examples of drag are the adverse effects of a headwind on the forward velocity of a competitive cyclist and the retarding effects of water drag on the efforts of a swimmer to move quickly ahead. In cycling on a flat course at speeds greater than 13 km/h (8 mph), most of the resistance to the power generated by a bicyclist is created by the air through which the cyclist’s body moves; relatively little bicycling power is lost to friction of the moving components of the bicycle or to the rolling resistance of the contact between the tire and road (Kale, 1991). It is also important to realize that the air drag increases as the square of the velocity of the moving object, i.e., if speed is doubled, the drag increases by four-fold (Kale, 1991).

Air drag offers great resistance in any sport requiring the athlete to move at relatively high velocities; such sports include speed skating–30-40 km/h (19-25 mph) at distances of 0.5-10 km (3-6 mi)–and sprint running–25-35 km/h (15-22 mph) at distances of 100-400 m. In fact, the air creates so much resistance in speed skating that the skaters must assume a tightly crouched posture to reduce their frontal areas exposed to air. Although this posture reduces leg power, it reduces air drag to an even greater extent and thus produces higher skating velocities. Swimmers move at relatively low velocities because they encounter large drag forces from the water as well as from the turbulence at the surface of the water. This drag encountered by a swimmer is not simply a function of body mass, but also of the geometry of the body as it moves through the water.

It is obvious that in events such as bicycling, speed skating, and possibly sprint running, each of which requires the athlete to move through the air at high speeds, the ultimate race time will be determined by the power generated relative to the air resistance. The same is true for the swimmer who must overcome the drag of the water at lower speeds. The main point is that the race velocity in these sports is a function of power production relative to the drag encountered at racing speeds. Therefore, velocity (performance) can be increased by improving power output and/or by reducing drag.

REDUCING RESISTANCE AND DRAG

In some sports, such as Olympic lifting, power lifting, and the shot put, the very nature of the competition makes it impossible to reduce resistance. If a competitive lifter chooses a low resistance–a lightweight barbell, that athlete is unlikely to win the competition. Likewise, the rules do not allow a shot putter to choose a lightweight shot. However, there are methods that can be used in many sports to reduce resistance or drag. Here are a few examples:

Use Skillful Technique. Competitors in wrestling, judo, rugby, American football, and other “contact” sports can reduce the resistance applied by opponents by skillful misdirection movements that trick the opponents into resisting in the wrong direction. These techniques are learned through many years of practice under the instruction of skillful coaches.

Use Aerodynamic and Hydrodynamic Equipment and Body Postures. In some sports, effective techniques have been employed to reduce resistance and drag in air and water. The designs of golf balls and javelins have become more aerodynamic over the years, and the resulting reductions in air drag have improved the flight characteristics of both. In cycling, riders wear aerodynamic helmets and skintight clothing and assume crouch positions over the handle bars (“aero bars”) to minimize wind resistance. In swimming, body position in the water and stroke mechanics are optimized by careful study of underwater videos so that the swimmer reduces water drag as much as possible. Also, engineers have successfully modified the designs of rowing shells, canoes, kayaks, sailboats, oars, and paddles to minimize water drag in competitive events.

Reduce Body Mass. Athletes should carefully consider whether they can effectively reduce resistance or drag by reducing body weight. For pole vaulters, high jumpers, long jumpers, and triple jumpers, gravity is the principal resistance that must be overcome, and body weight is responsible for nearly all of this effect of gravity. Therefore, if these athletes can reduce their body weights without equivalent reductions in their abilities to skillfully generate muscular power, their performances should improve. Of course, if the body weight loss leads to a serious loss of muscular power, performance may well be worsened, not improved. Competing at an effectively low body weight is also critical for distance runners, endurance cyclists, and cross-country skiers. In these sports, the resistance of gravity is a crucial factor in determining performance; in addition, at the higher velocities of cycling, air drag is a major type of resistance that must be overcome, and a smaller frontal body surface area can reduce that resistance.

Weight reduction is not so much of an issue in swimming because the body mass is buoyed up by being immersed in water. However, to the extent that reductions in body weight help reduce water drag, weight loss could be of benefit in swimming, too. Differences in swimmers’ individual body builds could play a significant role in determining whether or not weight loss improves swim performance. For example, weight loss may be quite ineffective in a swimmer who already presents a small frontal area and who tends to lose weight mostly in the thighs. However, if a swimmer has exceptionally large shoulders and a large chest, and if the mass of these areas can be reduced effectively through a weight loss program, such an approach could shave time off that swimmer’s personal records.

PROVIDING EFFICIENT SUSTAINED POWER OUTPUT TO OVERCOME RESISTANCE AND DRAG

Power is the ability to apply force through a distance quickly. In other words, power can be thought of as a combination of strength and speed. Interestingly, the sport of power lifting is misnamed because only strength, not speed, is required to be successful; as long as the barbell is moved appropriately, time is of no importance. On the other hand, a person could have exceptionally strong leg muscles and be a pitiful high jumper, sprinter, or long jumper if that strength could not be brought to bear quickly.

Unfortunately, absolute maximal muscular power can be sustained for only a fraction of a second. Thus, assuming equal resistance or drag, the champion in a sport event will not necessarily be the competitor who can produce the greatest maximal power, but instead will be the one who can sustain the greatest power output to overcome the resistance or drag for the duration of the event. This duration may be only a second or two, such as in power lifting, or many hours, such as in an Ironman triathlon.

The ability to sustain a high power output to efficiently overcome resistance or drag involves two major factors–the ability to sustain energy production by the muscles and the ability to apply that muscular energy efficiently to overcome resistance or drag.

SUSTAINING ENERGY PRODUCTION BY THE MUSCLES

When energy requirements are extremely high, such as during a sprint in track or swimming or during an Olympic weightlifting event, most of the muscular energy is supplied by two fuels, phosphocreatine (PCr) and glycogen, that are stored in small amounts in the muscles. Because these two fuels can be broken down for energy without the use of oxygen, this is known as anaerobic (without air) energy production. Aerobic energy production occurs at a much slower rate as fats and carbohydrates are broken down with the aid of oxygen in the muscles.

Sustainable Energy Expenditure in Brief, High-Power Events

Brief, high-power activities such as weightlifting and sprinting rely largely on the anaerobic breakdown of PCr and muscle glycogen for energy. When estimates of anaerobic energy production are coupled with simultaneous measurements of aerobic energy production, the approximate relative contributions of these two energy sources during various phases of exercise lasting from 0-180 s are as shown in Table 1. It is clear from the table that the percentage anaerobic contribution to energy production falls off rapidly as the exercise duration increases.

Both PCr degradation and anaerobic glycolysis are activated instantaneously at the onset of high-intensity exercise. Measurements of PCr and lactate from muscle biopsies taken following as little as 1-10 s of electrical stimulation (Hultman & Sjoholm, 1983) and after sprint cycling (Boobis et al., 1982; Gaitanos et al., 1993; Jacobs et al., 1983) confirm the rapid breakdown of PCr and rapid accumulation of lactate. At the onset of less intense exercise, a similar instantaneous activation of both PCr degradation and anaerobic glycolysis occurs but at a much slower rate because the mismatch between energy demand and aerobic supply is reduced during submaximal exertion.

Rate of Anaerobic Energy Production During Exercise

The rate of anaerobic energy provision is critical to success in sports that require the development and short-term maintenance of high power outputs. World-class power lifters and weightlifters can produce power outputs that are 10-20 times that required to elicit the maximal rate of aerobic energy provision, which is estimated by the maximal rate at which the athlete can consume oxygen (VO2max). However, such high power outputs can be maintained for only a fraction of a second. Sprinters can achieve power outputs that are 3-5 times the power output that elicits VO2max, but they can sustain that power output for only about 10 s. However, power output over a 30-40 s sprint can still be sustained at twice the power output at VO2max. Estimates of the rates of anaerobic provision of energy have been calculated from biochemical changes in muscles following intense exercise lasting from 1.3 to 200 s (Spriet, 1994). These studies used non-elite athletes who performed sprint cycling, sprint running, or repeated knee extensions or who underwent electrical stimulation of their muscles. The highest measured rates for energy production from PCr and anaerobic glycolysis during various types of exercise lasting from 1.3-10 s were each approximately 250-500% of the estimated maximal rate of energy provision from aerobic metabolism. In other studies of sprint cycling for 6-10 s, energy production rates from PCr and anaerobic glycolysis combined were about 400-750% of that during maximal aerobic metabolism (Boobis et al., 1982; Jacobs et al., 1983).

The anaerobic energy provision rates decrease when averaged over longer periods of time. In studies that examined intense exercise for 30 s, the average energy provision rate from PCr was about 70-100% of that from maximal aerobic metabolism; anaerobic glycolysis provided energy at a rate estimated to be 220-330% of that from maximal aerobic metabolism (Spriet, 1994). The large decrease in energy produced from PCr when averaged over 30 s, as compared to less than 10 s, indicates that the PCr store becomes depleted between 10 and 30 s of intense exercise. Thus, for maximal exertion lasting longer than about 30 s, it appears that only glycolysis can provide for further anaerobic energy production.

Anaerobic Energy Production During Intermittent High-Power Exercise

Many athletes repeatedly engage in bursts of high-intensity exercise with varying amounts of recovery time between exercise bouts. Examples include a wide receiver in American football, a basketball player in repeated fast break situations, or a swimmer or track athlete during interval training. Most of the energy for short bouts of high-intensity exercise is derived from anaerobic sources; therefore, the ability to recover during rest periods is essential for success in this type of activity. Many studies have examined the performance effects of intermittent high intensity exercise, but few have examined the anaerobic metabolism associated with this type of metabolic stress. Examples of the exercise models that have been studied and provided some conclusions include: 10 bouts of sprint cycling, each lasting 6 s with rest periods of 30 s; four bouts of sprint cycling for 30 s with 4-min rest periods; and two bouts of knee extension exercise to exhaustion in 3 min with 10-60 min of recovery (Bangsbo et al., 1992; Gaitanos et al., 1993; McCartney et al., 1986). Muscle biopsy measurements demonstrated that PCr was decreased by approximately 50% after 6 s and by 75-80% during longer sprints. The PCr is quickly resynthesized during recovery, reaching 50% of rest values by 30-60 s and about 80% by 2-4 min. With repeated sprinting, energy production from anaerobic glycolysis is progressively more difficult to achieve. Presumably, the accumulation of lactic acid in the active muscles plays a major role in the inability to continue producing energy by anaerobic glycolysis. Therefore, after repeated bursts of exercise, PCr is the only potential anaerobic energy source that can be relied upon. However, as described above, it is essential that adequate rest be provided in between intermittent exercise bouts to allow PCr stores to be replenished in the muscles.

Sustained Aerobic Energy Production

The maximal rate of aerobic energy production (VO2max) can be sustained for only about 8-10 min by elite athletes. In events lasting longer than 8-10 min, the best competitor among those with similar values for VO2max is usually the one who can sustain aerobic energy production at the greatest proportion of his or her maximal rate, that is, at the greatest percentage of the VO2max. This in turn is largely dependent on the extent to which the athlete can produce energy aerobically at a high rate without accumulating a large amount of lactic acid in the blood. In other words, the athlete who produces a large amount of lactic acid at a given speed of running, swimming, or cycling cannot continue to perform at that pace for as long as the athlete who does not accumulate as much lactic acid. An athlete who has the ability to exercise at a high intensity before blood lactic acid begins to accumulate is said to have a high lactate threshold (Coyle et al., 1988; Holloszy & Coyle, 1984). An athlete’s lactate threshold seems to be a better indicator of endurance performance lasting 30 min to 4 h than does the VO2max (Coyle et al., 1988, 1991).

This is because the lactate threshold is a better index of the athlete’s ability to sustain a high rate of energy expenditure for the duration of the competition.

Role of Nutrition in Determining Sustainable Energy Production

Two nutrients, carbohydrate and water, are the dietary constituents that have repeatedly been shown to be most important for optimizing endurance performance. Muscles obviously cannot produce energy without fuels derived from nutrients obtained in the diet, and carbohydrate is an obligatory fuel for high-caliber sport performance. It is well established that dietary carbohydrate consumption before, during, and after exercise can make an important contribution to performance. Carbohydrate consumption acts primarily by increasing the body’s stores of glycogen in muscles and in the liver before exercise and by increasing the availability of glucose for use by the muscles during exercise (Coggan & Swanson, 1992; Costill & Hargreaves, 1992; Coyle, 1991; Williams, 1993). Fluid intake during prolonged exercise is also required to counteract the debilitating effects of exercise and heat on cardiovascular function and on body temperature regulation. When dehydration reduces blood volume, oxygen delivery to the muscles by the blood can be compromised, and this reduces the ability of the muscles to produce energy aerobically. Dehydration also compromises the ability of the body to regulate its temperature, resulting in eventual lethargy and potential heat illness, both of which adversely affect the athlete’s ability to sustain a high rate of energy production. Carbohydrate-electrolyte beverages are advocated as the most effective way to supply both carbohydrate and fluid to the body during exercise (Coggan & Swanson, 1992; Gisolfi & Duchman, 1992).

IMPROVING THE ABILITY TO SUSTAIN ENERGY PRODUCTION AT A HIGH RATE

Here are some ways that athletes may be able to improve their abilities to sustain high rates of energy production so they can sustain greater power output to overcome resistance and drag:

At the onset of a training season, the athlete should establish a solid aerobic training foundation by training at relatively low intensities for long durations. This will help develop a greater blood volume, an improved ability of the heart to pump blood, and better networks of capillaries in the trained muscles. These cardiovascular adaptations will lead to an improved delivery of oxygen to the muscles and an enhanced ability of the muscles to sustain high rates of aerobic energy production.

For the bulk of the athlete’s training, the specific muscle groups involved in the competitive event should be overloaded, and the athlete should train at a pace or intensity similar to that used in competition (Hickson, 1977, 1985). Such training can lead to improved stores of glycogen and PCr in the trained muscles so that greater energy reserves will be present in the muscles before competition begins. Furthermore, metabolic adaptations to this type of training are likely to enhance the ability of the muscles to utilize fat for energy and to spare muscle glycogen, resulting in less lactic acid production and less accumulation of lactic acid in the blood at a given pace or intensity (Holloszy & Coyle, 1984). This means that the athlete’s lactate threshold will be increased so that aerobic energy production can be sustained longer at a greater rate than was possible before training.

During high intensity, anaerobic interval training, the duration of recovery intervals should be sufficient–usually between 30 s and 4 min–to allow the muscles to replenish most of the PCr depleted in the previous exercise interval. If these recovery intervals are too brief, the supply of PCr in the exercising muscles will be inadequate to provide energy anaerobically at a high rate (Gaitanos et al., 1993; McCartney et al., 1986). This means that the athlete will be forced to exercise at a lower intensity (slower pace) and that inappropriate muscle groups may be recruited to accomplish subsequent exercise intervals. If these events occur, the athlete will be learning incorrect movement patterns during training that may adversely affect competitive performance.

The athlete should receive adequate rest–approximately 24 h–between exhaustive training sessions to allow for total replenishment of depleted glycogen stores in the muscles prior to the next training session (Coyle, 1991). Otherwise, the quality of the next training session may be compromised because the athlete’s muscles will be easily depleted of one of their main fuels. In addition, training intensity and duration should be gradually reduced during the week before a competitive event so that the athlete’s energy reserves are fully loaded before competition.

The athlete should drink plenty of fluids before, during, and after exercise to avoid becoming dehydrated. Dehydration can lead to a diminished ability to deliver oxygen to the muscles, heat cramps, heat exhaustion, and even heat stroke, all of which can impair muscular energy production.

On a daily basis, the athlete should consume a diet high in carbohydrate, about 8 g of carbohydrate per kilogram of body weight (4 g/lb). This will ensure that the muscles can store extra glycogen and may help sustain energy production during competition.

Preliminary evidence suggests that dietary creatine supplementation may increase PCr stores in muscles (Dalsom et al., 1995) and perhaps improve performance in events such as fastbreak basketball that require repeated brief exertions. The extent to which creatine supplementation proves to be useful in actual sport settings remains to be seen.

During prolonged exercise, the athlete should consume carbohydrate-electrolyte drinks containing approximately 6% carbohydrate (glucose, sucrose, or maltodextrins) and a small amount of sodium to help maintain an adequate carbohydrate energy supply to the muscles and to minimize dehydration. Volumes of 150-250 mL (5-8 oz) should be consumed every 15-20 min to replace most, if not all, of the sweat lost by the athlete during exercise (Montain & Coyle, 1992).

MECHANICAL EFFICIENCY: A MAJOR DETERMINANT OF EFFECTIVE POWER OUTPUT

Mechanical efficiency for a sporting event is the ratio of the mechanical power output to the total energy expended to produce that power. Typically, both power output and energy expenditure are expressed in watts (W), and the ratio is expressed as a percentage. For example, if a cyclist expends energy at the rate equivalent to 5 L of oxygen per minute (1745 W) to produce 400 W of power on a bicycle ergometer, the mechanical efficiency would be (400/1745) 100 = 23%. Two of the principal factors that determine the mechanical efficiency of an athlete in a sport event are 1) the efficiency with which the active muscles convert the chemical energy stored in carbohydrate and fat to the mechanical energy required to shorten the contractile elements in the muscles, and 2) the neuromuscular skill with which the athlete performs the event.

Role of Muscle Efficiency in Determining Mechanical Efficiency

Muscle efficiency has two components, the first of which is the efficiency with which chemical energy from carbohydrate and fat is converted to adenosine triphosphate (ATP), the only form of chemical energy that can power muscle contraction. The process of ATP synthesis is about 40% efficient, i.e., 40% of the metabolic energy in carbohydrate and fat is transferred into ATP synthesis, whereas 60% of the energy is lost as heat (Kushmerick, 1983; Kushmerick & Davies, 1969). This efficiency of ATP synthesis is fairly constant among individuals.

The second component of muscle efficiency, i.e., the efficiency with which the energy released during ATP hydrolysis is converted to muscle fiber shortening, is more variable than is the efficiency of converting stored fuels to ATP. The efficiency of ATP hydrolysis is dependent on the velocities of muscle contraction (Goldspink, 1978; Kushmerick & Davies, 1969). A peak efficiency of approximately 60% or more can be elicited from myofilaments contracting at one- third of maximal velocity; i.e., the velocity of peak efficiency (Kushmerick, 1983; Kushmerick & Davies, 1969). Thus, slow-twitch muscle fibers obviously have slower velocities of peak efficiency than do fast-twitch fibers (Fitts et al., 1989).

Mechanical efficiency when cycling at 80 rpm is directly related to the percentage of slow- twitch muscle fibers in the vastus lateralis muscles (Coyle et al., 1992). It seems that when cycling at this cadence, the velocity of muscle fiber shortening in the vastus lateralis is close to one-third maximal velocity of the slow-twitch fibers (Coyle et al., 1992). This makes slow-twitch muscle fibers substantially more efficient than fast-twitch muscle fibers at converting ATP into muscular power when cycling at 80 rpm (Coyle et al., 1992; Goldspink, 1978).

Muscle fiber type has a large effect on mechanical efficiency, which in turn has a large influence on sustainable power output as measured during a 60-min bout of cycling in a homogeneous group of cyclists (Horowitz et al., 1994). The cyclists in this study were paired and divided into two groups based upon the percentage (i.e., above or below 56%) of slow-twitch muscle fibers in their vastus lateralis muscles. One group possessed a normal distribution of fiber types, with an average of 48% slow twitch fibers. The other group had 72% slow-twitch fibers on average. These two groups were identical in VO2 max as well as in the VO2 maintained during the ride. Therefore, they possessed the same aerobic energy expenditure potential for this type of task. However, the cyclists with a high percentage of slow-twitch fibers displayed significantly higher mechanical efficiencies and were therefore able to sustain a 9% greater power output (342 W vs. 315 W) during the 60-min ride. Clearly, endurance cycling performance is heavily influenced by mechanical efficiency, which in turn appears to be dependent on the rider’s muscle fiber type profile and the efficiency of ATP hydrolysis by the muscle.

Role of Neuromuscular Skill in Determining Mechanical Efficiency

No matter how efficiently one can transform chemical energy into mechanical energy in a given muscle fiber, the overall mechanical efficiency in a sports event will be poor if the athlete is poorly skilled. A good example of the importance of skill is the contrast in the freestyle swimming performances of novice and elite swimmers. The novice may produce a great deal of power, but because the swimmer is so unskillful, the power output is misdirected so that lots of thrashing about occurs with little forward velocity. The elite swimmer, on the other hand, has learned to swim rapidly and gracefully, using only those muscle fibers required to execute the stroke effectively. Neuromuscular skill obviously plays a greater role in determining the mechanical efficiency for some sports, e.g., swimming and wrestling, than it does for others, e.g., running and power lifting, but even small differences in skill can have a major impact on performance in any sport at the elite level.

IMPROVING THE ATHLETE’S ABILITY TO PROVIDE POWER OUTPUT IN AN EFFICIENT MANNER

There is little that the athlete can do to improve muscle efficiency because the chemical efficiency of converting fuels to ATP and the proportion of slow-twitch fibers involved in various movements are largely determined by heredity. An exception may be that athletes over many months of training may learn to recruit more of the efficient slow-twitch muscle fibers and fewer of the less efficient fast-twitch fibers. In addition, there are three important steps that can be taken to improve the skill with which power output is applied.

The athlete should obtain the technical advice of competent coaches who can explain how movement patterns should be altered to become more skillful. Often the coach can rely upon personal experience and observation to make critical improvements in an athlete’s technique.

Video analysis of the athlete’s performance can provide clues about changes in movement patterns that can be made to improve efficiency. The assistance of a sport biomechanist or a coach well-educated in biomechanics could be important in this phase of the athlete’s preparation.

The athlete must repeat the appropriate movement patterns in a skillful manner many thousands of times during practice so the nervous system learns to perform the movement correctly every time throughout the entire duration of competition. There is no substitute for skillful repetition of muscular activities to ensure that such activities are likely to remain skillful in the heat of competition.

SUMMARY

For most competitive sports, improving the performance of an athlete can be accomplished by reducing the resistance or drag that must be overcome or by increasing the athlete’s ability to sustain a high power output to overcome that resistance or drag. Reducing air resistance or water drag typically involves improving body position in the air or water by minimizing the frontal surface area of the athlete that is exposed to the air or water. Sometimes the apparel or equipment used in the sport, e.g., helmets, swimwear, bicycles, and rowing shells, can be made more aerodynamic or hydrodynamic to reduce resistance or drag.

Increasing sustainable power output requires that the athlete undergo a carefully designed training program that will improve the athlete’s abilities to: 1) produce metabolic energy by both aerobic and anaerobic means, 2) sustain aerobic energy production at high levels before lactic acid accumulates excessively in the blood, 3) recruit more of the efficient slow-twitch muscle fibers at exercise intensities used in competition, and 4) become more skillful by recruiting fewer non- essential muscle fibers during competition. Careful attention to maintaining a sufficient intake of fluids and carbohydrate before, during, and after strenuous competition and training sessions is also important.

Although it is apparent that some uniquely gifted athletes are able to win consistently even when their approaches to training are obviously not optimal for reducing resistance or drag and for enhancing their sustainable power outputs, it is clear that such athletes cannot achieve their full potentials in sport without addressing these two basic principles.

* This article was adapted from “Introduction to Physiology and Nutrition for Competitive Sport,” by E.F. Coyle, L. Spriet, S. Gregg, and P. Clarkson, which appeared in D.R. Lamb, H.G. Knuttgen, and R. Murray (eds.), Perspectives in Exercise Science and Sports Medicine, Vol. 7: Physiology and Nutrition for Competitive Sport. Carmel, IN: Cooper Publishing Group, 1994, pp. xv-xxxix. The author is especially grateful to Edward Coyle, Ph.D. and Lawrence Spriet, Ph.D. who contributed much of the text for this article.

References

Bangsbo, J., P.D. Gollnick, T.E. Graham, C. Juel, B. Kiens, M. Mizuno, and B. Saltin (1990). Anaerobic energy production and O2 deficit-debt relationship during exhaustive exercise in humans. J. Physiol. (London) 422:539-559.

Bangsbo, J., T.E. Graham, B. Kiens, and B. Saltin (1992). Elevated muscle glycogen and anaerobic energy production during exhaustive exercise in man. J. Physiol. (London) 451:205- 227. Boobis, L.H., C. Williams, and S.A. Wooton (1982). Human muscle metabolism during brief maximal exercise (abstract). J. Physiol. (London) 338:21P-22P.

Coggan, A.R., and S.C. Swanson (1992). Nutritional manipulation before and during endurance exercise: effects on performance. Med. Sci. Sports Exerc. 24:S331-S335.

Costill, D.L., and M. Hargreaves (1992). Carbohydrate nutrition and fatigue. Sports Med. 13:86-92.

Costill, D.L., and P.R. Gardetto (1989). Effect of swim exercise training on human muscle fiber function. J. Appl. Physiol. 66:465-475.

Coyle, E.F. (1991). Timing and methods of increased carbohydrate intake to cope with heavy training, competition and recovery. J. Sports Sci. 9:29-52.

Coyle, E.F., A.R. Coggan, M.K. Hopper, and T.J. Walters (1988). Determinants of endurance in well trained cyclists. J. Appl. Physiol. 64:2622-2630.

Coyle, E.F., M.E. Feltner, S.A. Kautz, M.T. Hamilton, S.J. Montain, A.M. Baylor, L.D. Abraham, and G.W. Petrek (1991). Physiological and biomechanical factors associated with elite endurance cycling performance. Med. Sci. Sports Exerc. 23:93-107.

Coyle, E.F., L.S. Sidossis, J.F. Horowitz, and J.D. Beltz (1992). Cycling efficiency is related to the percentage of Type I muscle fibers. Med. Sci. Sports Exerc. 24:782-788.

Coyle, E.F., L. Spriet, S. Gregg, and P. Clarkson (1994). Introduction to physiology and nutrition for competitive sport. In D.R. Lamb, H.G. Knuttgen, and R. Murray (eds.) Perspectives in

Exercise Science and Sports Medicine, Vol. 7: Physiology and Nutrition for Competitive Sport. Carmel, IN: Cooper Publishing Group, 1994, pp. xv-xxxixFitts, R.H.,

Dalsom, P.D., K. Soderlund, D. Sjodin, and B. Ekblom (1995). Skeletal muscle metabolism during short duration high-intensity exercise: Influence of creatine supplementation. Acta Physiol. Scand. 154:303-310.

Gaitanos, G.C., C. Williams, L.H. Boobis, and S. Brooks (1993). Human muscle metabolism during intermittent maximal exercise. J. Appl. Physiol. 75:712-719.

Gisolfi, C.V., and S.M. Duchman (1992). Guidelines for optimal replacement beverages for different athletic events. Med. Sci. Sports Exerc. 24:679-687.

Goldspink, G. (1978). Energy turnover during contraction of different types of muscle. In: E. Asmussen and K. Jorgensen (eds.) Biomechanics VI-A. Baltimore: University Park Press, pp. 27-39.

Hickson, R.C., H.A. Bomze, and J.O. Holloszy (1977). Linear increase in aerobic power induced by a strenuous program of endurance exercise. J. Appl. Physiol. 42:372-376.

Hickson, R.C., C. Foster, M.L. Pollock, T.M. Galassi, and S. Rich (1985). Reduced training intensities and loss of aerobic power, endurance, and cardiac growth. J. Appl. Physiol. 58:492-499. Holloszy, J.O., and E.F. Coyle (1984). Adaptations of skeletal muscle to endurance exercise and their metabolic consequences. J. Appl. Physiol. 56:831-838.

Horowitz, J.F., L.S. Sidossis, and E.F. Coyle (1994). High efficiency of Type I muscle fibers improves performance. Int. J. Sports Med. 15:152-157.

Hultman, E., and H. Sjoholm (1983). Substrate availability. In: H.G. Knuttgen, J. A. Vogel, and J. Poortmans (eds.) Biochenistry of Exercise, Vol. 5. Champaign, IL:Human Kinetics, pp. 63-75.

Jacobs, I., P. Tesch, O. Bar-Or, J. Karlsson, and R. Dotan (1983). Lactate in human skeletal muscle after 10 and 30 s of supramaximal exercise. J. Appl. Physiol. 55:365-367.

Kushmerick, M.J. (1983). Energetics of muscle contraction. In: L.E. Peachey, R.H. Adrian, and S.R. Geiger (eds.) Handbook of Physiology, Section 10: Skeletal Muscle. Bethesda, MD: American Physiological Society, pp. 189-236.

Kushmerick, M.J., and R.E. Davies (1969). The chemical energetics of muscle contraction II. The chemistry, efficiency, and power of maximally working sartorius muscle. Proc. R. Soc., Ser. B. 1174:315-353.

Kyle, C.R. (1991). Ergogenics of bicycling. In: D.R. Lamb and M.H. Williams (eds.) Perspectives in Exercise Science and Sports Medicine, Vol 4: Ergogenics–Enhancement of Performance in Exercise and Sport. Carmel, IN: Brown & Benchmark, pp. 373-413.

McCartney, N., L.L. Spriet, G.J.F. Heigenhauser, J.M. Kowalchuk, J.R. Sutton, and N.L. Jones (1986). Muscle power and metabolism in maximal intermit-tent exercise. J. Appl. Physiol. 60:1164-1169.

Montain, S.J., and E.F. Coyle (1992). The influence of graded dehydration on hyperthermia and cardiovascular drift during exercise. J. Appl. Physiol. 73:1340-1350.

Spriet, L.L. (1994). Anaerobic metabolism during high-intensity exercise (Chapter 1). In: M. Hargreaves (ed.) Exercise Metabolism. Champaign, IL: Human Kinetics (In press).

Williams, C. (1993). Carbohydrate needs of elite athletes. In: A.P. Simopoulos and K.N. Pavlou (eds.) World Review of Nutrition and Dietetics, Vol. 71: Nutrition and Fitness for Athletes. Basel: Karger, pp. 34-60.

The Gatorade Sports Science Institute® was created to provide current information on developments in exercise science, sports nutrition, and sports medicine and to support the advancement of sports science research.

Used with Permission from the Gatorade Sports Science Institute