Heat & Hydration

Carbohydrate needs during exercise related to body weight

Carbohydrate needs during exercise related to body weight

An athlete’s body weight has very little to do with carbohydrate requirements.

The amount of carbohydrate needed during exercise varies depending on multiple factors

The amount of carbohydrate needed during exercise varies depending on multiple factors

Jeukendrup explains that the amount of carbohydrates needed during exercise depends on the intensity, type and duration of activity.

The Two Categories of Carbohydrates

The Two Categories of Carbohydrates

Carbohydrate sources can be divided into two categories. Some carbohydrates, like glucose and sucrose, are used rapidly, while others, like fructose, are used more slowly.

Properties of anabolic post-exercise protein sources

Properties of anabolic post-exercise protein sources

van Loon explains that rapidly digested and absorbed protein sources rich in the amino acid leucine, such as whey protein, are most anabolic following exercise.

The amount and type of carbohydrate athletes need for recovery

The amount and type of carbohydrate athletes need for recovery

van Loon explains the amount of carbohydrate needed after a workout and what sources athletes should look to consume.

Why tired athletes may consume more calories

Why tired athletes may consume more calories

Sleep-deprived people may consume more food.

GI Distress during exercise

GI Distress during exercise

Approximately 30-50% of athletes experience GI problems during exercise.

Recommendations on the use of anti-inflammatory drugs

Recommendations on the use of anti-inflammatory drugs

Experts recommend avoiding NSAID use before a marathon due to increased risk of GI problems.

Avoiding GI Distress during a race

Avoiding GI Distress during a race

Keys to avoiding GI distress include hydration and avoiding fiber, protein, fat and lactose rich foods.

Foods that may cause GI distress

Foods that may cause GI distress

Foods rich in fiber, protein, fat and lactose slow gastric emptying and should be avoided before and during exericse.

Non-nutritional causes of GI distress

Non-nutritional causes of GI distress

Movement of organs and decreased blood flow may contribute to GI issues during exercise.

Determining risk for GI distress

Determining risk for GI distress

Factors that may increase an athlete's chance of experiencing GI distress.

Tips to avoid GI distress

Tips to avoid GI distress

During exercise of less than one hour, GI distress may be prevented by gargling rather than consuming carbohydrate.

Cause of Heat Cramps

Cause of Heat Cramps

Heat cramps are a result of excessive sweat lost and a consequent sodium deficit.

Limiting Warm-Ups Before Exercise in the Heat

Limiting Warm-Ups Before Exercise in the Heat

Prior to exercise in the heat, athletes may gain a thermoregulatory and performance advantage by 'pre-cooling' their bodies rather than using a traditional 'warm-up.'

Acclimatization to Hot and Humid Conditions

Acclimatization to Hot and Humid Conditions

Athletes can acclimatize to a hot, humid environment. However, at high intensities the athlete will still have a difficult time evaporating sweat and will feel the effect of the environment.

Benefits of Sweat Testing

Benefits of Sweat Testing

Sweat tests can help identify individual fluid and electrolyte needs and improve hydration strategies.

Tips for Performance in the Heat

Tips for Performance in the Heat

To maximize performance, athletes should to acclimatize to the heat, practice proper hydration, and cool the body during breaks.

Heat Strain versus Heat Stress

Heat Strain versus Heat Stress

Heat stress is the effect of the environment on the athlete, whereas heat strain describes how the athlete's body responds to the environmental stress.

Causes of Fatigue During Prolonged Exercise in the Heat

Causes of Fatigue During Prolonged Exercise in the Heat

Primary causes of fatigue during exercise in the heat include cardiovascular strain and high rates of glycogen utilization.

Importance of Skin Temperature and Core Temperature

Importance of Skin Temperature and Core Temperature

Both skin and core temperature are related to fatigue in the heat; skin temperature is close to environmental temperature and is related to the perception of heat felt by the athlete.

The Effect of Dehydration on Performance

The Effect of Dehydration on Performance

A lack of water in the body inhibits sweating which causes body temperature to rise, ultimately reducing the athlete's ability to continue exercising.

Effect of Fluid Intake on Thermoregulation During Exercise

Effect of Fluid Intake on Thermoregulation During Exercise

Fluid intake before and during exercise can help the body maintain an appropriate body temperature.

The Contribution of Genetics to Athletic Performance

The Contribution of Genetics to Athletic Performance

Genetics explain about 50 percent of performance outcomes, nutrition and other aspects of gene regulation also play important roles.

Using Genetics to Predict Individual Responses to Nutrition

Using Genetics to Predict Individual Responses to Nutrition

Predicting an individual's response to nutrition is challenging, since scientists need to account for both the genetic variation of the athlete and the gut biome.

Sports Drink Recommendations for Exercise in the Heat and Cooler Conditions

Sports Drink Recommendations for Exercise in the Heat and Cooler Conditions

Exercise in the heat results in greater sweat losses as compared to a thermoneutral environment, resulting in a greater need to replace both fluid and electrolytes.

Recognizing Over-Hydration in Athletes

Recognizing Over-Hydration in Athletes

Two warning signs of over-hydration during exercise are 1) drinking large volumes of water without producing urine and 2) gaining weight over the course of a training session or competition.

The Concept of a Critical Core Temperature

The Concept of a Critical Core Temperature

If a critical core temperature does contribute to fatigue, it is likely related to the environment.

Effect of Caffeine on Thermoregulation

Effect of Caffeine on Thermoregulation

Studies have shown that moderate intake of caffeine will not impair fluid balance or thermoregulation.

Nitrates alter the energy cost of exercise

Nitrates alter the energy cost of exercise

The dietary nitrates in beet root juice alter running economy and cycling efficiency to help improve performance.

Beet root juice may improve the exercise tolerance of older individuals

Beet root juice may improve the exercise tolerance of older individuals

Jones has found that beet root juice is effective for increasing older individuals’ exercise tolerance and lowering blood pressure.

Nitrates have important effects on physiological processes

Nitrates have important effects on physiological processes

Jones explains why nitric oxide is important to various physiological processes, including the delivery of oxygen to muscles and the production of oxidative energy.

Beet Root Juice Faciliates the Conversion from Nitrate to Nitric Oxide

Beet Root Juice Faciliates the Conversion from Nitrate to Nitric Oxide

Jones explains that beet root juice contains an abundance of inorganic nitrate, which converts to nitric oxide in the body. Nitric oxide helps deliver blood and oxygen to muscle tissue.

Nitrate-rich beet root juice reduces the oxygen cost of exercise

Nitrate-rich beet root juice reduces the oxygen cost of exercise

Jones explains how he discovered beet root juice as a nitrate source.

Rinsing the mouth with carbohydrate can help improve performance

Rinsing the mouth with carbohydrate can help improve performance

Jeukendrup explains that mouth rinsing can help improve performance. Sensors in the mouth signal the brain which sends a message to the muscles.

Carbohydrate supplements can come in many forms, such as a drink, gel, chews or a bar

Carbohydrate supplements can come in many forms, such as a drink, gel, chews or a bar

While the form of carbohydrate delivery doesn’t impact performance, it is important that carbohydrate supplements are low in fat, protein and fiber.

Carbohydrate and fat use during the later stages of exercise

Carbohydrate and fat use during the later stages of exercise

The thought that the body switches from carbohydrates to fat for energy is a myth. While the levels do change, athletes burn both at the same time.

Advice Given to Athletes on Carbohydrate Loading Has Changed since the 1960’s

Advice Given to Athletes on Carbohydrate Loading Has Changed since the 1960’s

Experts have determined that extreme carbohydrate loading is unneccessary. Athletes can gradually increase their carbohydrate intake while reducing training load leading up to the race.

RECOGNIZING OVER-HYDRATION IN ATHLETES

RECOGNIZING OVER-HYDRATION IN ATHLETES

Stachenfeld explains the circumstances when over-hydration may become an issue.

PREVENTING HYPONATREMIA

PREVENTING HYPONATREMIA

Hyponatremia is not very common. Stachenfeld discusses strategies for susceptible athletes to prevent hyponatremia.

THE DEFINITION OF HYPONATREMIA

THE DEFINITION OF HYPONATREMIA

Hyponatremia is a fall in blood sodium below a level that can be tolerated by an individual.

DAILY PROTEIN NEEDS FOR ENDURANCE ATHLETES

DAILY PROTEIN NEEDS FOR ENDURANCE ATHLETES

A normal, healthy diet requires about 10-15% of the total energy requirement come from protein.

BCAA’S DON’T PROVIDE HELPFUL ENERGY TO ATHLETES

BCAA’S DON’T PROVIDE HELPFUL ENERGY TO ATHLETES

van Loon discusses why branched chain amino acids (BCAA’s) are not a good source of energy for athletes.

THE AMOUNT OF PROTEIN TO CONSUME AFTER A WORKOUT

THE AMOUNT OF PROTEIN TO CONSUME AFTER A WORKOUT

Ingesting about 20-25 grams of protein is sufficient to allow a maximal post-exercise muscle response.

ATHLETES MAY REQUIRE BIGGER DOSES OF PROTEIN BASED ON SIZE

ATHLETES MAY REQUIRE BIGGER DOSES OF PROTEIN BASED ON SIZE

Larger athletes may need to eat more protein after exercise because they require larger doses of protein to stimulate new protein synthesis.

THE AMOUNT OF PROTEIN ATHLETES SHOULD CONSUME POST-WORKOUT

THE AMOUNT OF PROTEIN ATHLETES SHOULD CONSUME POST-WORKOUT

Phillips recommends 20-25 grams of protein to stimulate the rate of new muscle synthesis; however, the specific amount of protein within this range depends on the size of the athlete.

CLEARING UP THE DIFFERENCE BETWEEN PROTEIN ISOLATES, CONCENTRATES AND HYDROSYLATES

CLEARING UP THE DIFFERENCE BETWEEN PROTEIN ISOLATES, CONCENTRATES AND HYDROSYLATES

Phillips explains why there is not a significant difference between protein isolates, concentrates and hydrosylates with respect to post-exercise recovery.

TYPES OF PROTEIN ATHLETES SHOULD CONSUME POST-WORKOUT

TYPES OF PROTEIN ATHLETES SHOULD CONSUME POST-WORKOUT

Phillips explains the types of protein athletes should choose post-workout.

THE IMPORTANCE OF SLEEP FOR ATHLETES

THE IMPORTANCE OF SLEEP FOR ATHLETES

Halson explains why sleep is important for sports performance.

THE CAUSES OF POOR SLEEP IN ATHLETES

THE CAUSES OF POOR SLEEP IN ATHLETES

Reasons some athletes suffer from poor sleep.

IMPORTANT TIPS ON IMPROVING SLEEP FOR ATHLETES

IMPORTANT TIPS ON IMPROVING SLEEP FOR ATHLETES

Two key components to improving sleep are routine and environment.

THE AMOUNT OF SLEEP NEEDED FOR AN ATHLETE

THE AMOUNT OF SLEEP NEEDED FOR AN ATHLETE

Researchers believe athletes should get at least eight hours of sleep per night.

HOW SLEEP AFFECTS PERFORMANCE?

HOW SLEEP AFFECTS PERFORMANCE?

Halson explains how too little sleep and sleep extensions affect performance.

ATHLETE SLEEP REQUIREMENTS COMPARED TO THE GENERAL POPULATION

ATHLETE SLEEP REQUIREMENTS COMPARED TO THE GENERAL POPULATION

An athlete has greater recovery needs since they usually expend more energy than the average population.

IMPORTANT NUTRIENTS FOR BRAIN DEVELOPMENT

IMPORTANT NUTRIENTS FOR BRAIN DEVELOPMENT

Fatty acids found in fish oil and antioxidants found in red fruit and berries are important for brain development.

TRAINING THE GUT

TRAINING THE GUT

Athletes can train their intestines to absorb carbohydrates during exercise, resulting in decreased GI problems and improved performance.

PREVENTING CRAMPS WITH PICKLE JUICE

PREVENTING CRAMPS WITH PICKLE JUICE

The sodium levels in pickle juice are very high, but it doesn't contain the right amount of fluid to rehydrate athletes.

PREVENTING HEAT CRAMPS

PREVENTING HEAT CRAMPS

The best way for athletes to prevent heat cramps is to match sweat losses with fluid and sodium intake.

A QUICK WAY TO ASSESS HYDRATION

A QUICK WAY TO ASSESS HYDRATION

Examining the color of urine is an easy way for athletes to assess their hydration status.

GENOMICS VERSUS TRANSCRIPTOMICS TO UNDERSTAND PERFORMANCE

GENOMICS VERSUS TRANSCRIPTOMICS TO UNDERSTAND PERFORMANCE

Genetics attempts to link DNA variations to performance. Transcriptomics takes into account DNA and environmental factors, making it easier to detect differences in performance.

THE FUTURE OF GENOMIC TECHNOLOGIES TO HELP ATHLETES

THE FUTURE OF GENOMIC TECHNOLOGIES TO HELP ATHLETES

In the future, genomics may be able to help athletes personalize their training approach and predict injury-related responses.

IMPORTANCE OF PRACTICING RACE DAY NUTRITION

IMPORTANCE OF PRACTICING RACE DAY NUTRITION

The most common nutrition mistake made by marathon runners is not practicing their race day nutrition plan during training.

BENEFITS OF STRENGTH TRAINING LATER IN THE DAY

BENEFITS OF STRENGTH TRAINING LATER IN THE DAY

If their goal is to increase muscle mass, athletes may want to train later in the day. This timing may associate their training with their largest intake of amino acids. Relaxing at night will also help to decrease metabolic stress, which impairs adaptations to training.

CHOOSING THE PRE-MARATHON DINNER

CHOOSING THE PRE-MARATHON DINNER

The night before a marathon is the last chance to fill muscle glycogen stores, so runners should choose foods high in carbohydrate. Good options are rice, potatoes or pasta.

BREAKFAST CONSIDERATIONS FOR RACE MORNING

BREAKFAST CONSIDERATIONS FOR RACE MORNING

The choice of what to eat for breakfast before a marathon is highly individual. The most important consideration is to get enough carbohydrate, at least 100 g, to have enough fuel for the race.

PHYSIOLOGIC ADAPTATIONS BASED ON TRAINING MODE

PHYSIOLOGIC ADAPTATIONS BASED ON TRAINING MODE

Endurance training will increase aerobic capacity, while strength training will increase muscle mass and alter the functionality of connective tissue.

NIGHTTIME EATING, WEIGHT LOSS, AND PROTEIN SYNTHESIS DURING SLEEP

NIGHTTIME EATING, WEIGHT LOSS, AND PROTEIN SYNTHESIS DURING SLEEP

Athletes looking to lose weight should balance energy intake and output, and eating before sleep is a personal preference. However, there could be an advantage to eating protein before sleep to promote protein synthesis.

RELATIONSHIP BETWEEN AMOUNT AND TIMING OF PROTEIN INTAKE

RELATIONSHIP BETWEEN AMOUNT AND TIMING OF PROTEIN INTAKE

The biggest misconception about protein consumption is the notion that "more is better." The right timing helps the body use more of the ingested protein for muscle adaptations.

ADVICE FOR ANTIOXIDANT CONSUMPTION

ADVICE FOR ANTIOXIDANT CONSUMPTION

Advice on the use of antioxidants depends on the type of training. Athletes should consume antioxidants during resistance training, but not endurance training.

THE ROLES OF FAT IN THE BODY

THE ROLES OF FAT IN THE BODY

Individuals should consume fat in their diet since this nutrient is an important fuel source, aids vitamin absorption, acts as shock absorber for organs and is a component of membranes.

TYPES OF DIETARY FAT AND PERFORMANCE

TYPES OF DIETARY FAT AND PERFORMANCE

During exercise fat stored in the muscle and adipose tissue supplies energy, so the type of dietary fat doesn't matter for performance. However, good health saturated fats should be limited and omega-3 fatty acids encouraged.

CARBOHYDRATES, ATHLETES AND WEIGHT LOSS

CARBOHYDRATES, ATHLETES AND WEIGHT LOSS

Carbohydrates are the main fuel source for an athlete during training, so this macronutrient should not be avoided when trying to lose weight.

THE ROLES OF SUGAR AND SALT IN A SPORTS DRINK

THE ROLES OF SUGAR AND SALT IN A SPORTS DRINK

Sugar and salt, along with water and flavor, are the key components of a sports drink. Carbohydrates, including sugars, provide fuel and salt helps replace sweat losses.

ENERGY SOURCES FOR FOOTBALL PLAYERS

ENERGY SOURCES FOR FOOTBALL PLAYERS

The game of football involves repeated, short, high-intensity bursts of muscle contraction. The preferred energy source for burst or sprint activities is carbohydrate.

ENERGY SOURCES FOR STOP-AND-GO SPORTS

ENERGY SOURCES FOR STOP-AND-GO SPORTS

Stop-and-go sports involve frequent transitions from one intensity to another. Therefore, the muscle relies heavily on carbohydrate as the main fuel source.

FLUID NEEDS DURING A RACE

FLUID NEEDS DURING A RACE

Fluid needs during a race are highly individual and athletes should determine and practice their hydration strategy during training.

BEVERAGE CHOICE DURING A RACE

BEVERAGE CHOICE DURING A RACE

The type of beverage to consume during a race is a personal decision. However, for races of longer durations, athletes should include electrolytes. Athletes should also plan ahead and train with the beverages availabe on the course.

Diet Composition for Muscle Gain

Diet Composition for Muscle Gain

To gain muscle mass, athletes should eat ~30% of their total calories from protein. It is also important the athlete is in positive energy balance and consumes additional calories from fat and carbohydrate.

Recovery Protein Needs for Endurance Athletes

Recovery Protein Needs for Endurance Athletes

Endurance-trained athletes, similar to resistance-trained athletes, should eat ~20-25 g high quality protein for recovery.

The Relationship of Protein and Muscle Mass in Endurance Athletes

The Relationship of Protein and Muscle Mass in Endurance Athletes

Due to the type of training stress and high energy expenditure, endurance athletes do not need to reduce protein intake to avoid gains in muscle mass. Dietary protein may help promote adaptations to endurance training.

Strength Increases in Powerlifters vs. Bodybuilders

Strength Increases in Powerlifters vs. Bodybuilders

Powerlifters are stronger than bodybuilders due to their type of training program.

Muscle Gains in Powerlifters vs. Bodybuilders

Muscle Gains in Powerlifters vs. Bodybuilders

The biological mechanism for muscle gain is exactly the same for powerlifters and bodybuilders.