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Introduction
1. Structure and function of body systems
2. Biomechanics of resistance exercise
3. Bioenergetics of exercise and training
4. Endocrine responses to resistance exercise
5. Adaptations to anaerobic training
6. Adaptations to aerobic endurance training
7. Age and sex differences in resistance exercise
8. Psychology of athletic preparation and performance
9. Sports nutrition
9.1 Standard nutrition guidelines for athletes
9.2 Macronutrients
9.3 Vitamins and minerals
9.4 Fluid and electrolytes
10. Nutrition strategies for maximizing performance
11. Performance-enhancing substances and methods
12. Principles of test selection and administration
13. Administration, scoring, and interpretation of selected tests
14. Warm-up and flexibility training
15. Exercise technique for free weight and machine training
16. Exercise technique for alternative modes and nontraditional implement training
17. Program design for resistance training
18. Program design and technique for plyometric training
19. Program design and technique for speed and agility training
20. Program design and technique for aerobic endurance training
21. Periodization
22. Rehabilitation and reconditioning
23. Facility design, layout, and organization
24. Facility policies, procedures, and legal issues
Wrapping up
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9.4 Fluid and electrolytes
Achievable CSCS
9. Sports nutrition

Fluid and electrolytes

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  • Water is the largest component of the body, making up 45-75% of body weight.
  • Functions of water:
    • Lubrication (joints, tissues)
    • Shock absorption (brain, spinal cord)
    • Body temperature regulation (cooling via sweat)
    • Nutrient transport and waste removal
    • Blood pressure maintenance
  • The body can’t survive more than a few days without water.

Fluid balance in athletes

  • Daily fluid intake recommendations (AI):
    • Men: 3.7 L (125.1 oz)
    • Women: 2.7 L (91.3 oz)
    • Pregnant women: 3.0 L
    • Lactating women: 3.8 L
  • Athletes may require more fluids, depending on:
    • Sweat rate
    • Environmental conditions (heat, humidity, altitude)
    • Clothing and equipment
  • Sweat loss and dehydration risk:
    • Linemen in football experience high sweat rates due to heavy gear.
    • Basketball players lose around 1.6-3.5 L (54.1-118.4 oz) per game.

Preventing dehydration

  • Dehydration risks:
    • Losing >2% of body weight from sweat impairs performance.
    • Symptoms include increased core temperature, heart rate, and perceived exertion.
  • Assessing hydration status:
    • Urine specific gravity (USG) and plasma osmolality are effective measures.
    • Urine color isn’t always reliable because vitamins and foods can change it.

Biomarkers of hydration status

Measure Practicality Validity (acute vs. chronic changes) EUH cutoff
Total body water Low Acute and chronic <2%
Plasma osmolality Medium Acute and chronic <290 mOsmol
Urine specific gravity High Chronic <1.020 g/ml
Urine osmolality High Chronic <700 mOsmol
Body weight High Acute and chronic <1%

Electrolytes and performance

  • Electrolytes lost in sweat:
    • Sodium chloride (NaCl) - most significant loss
    • Potassium, magnesium, calcium - minor losses
  • Sodium functions:
    • Helps retain fluid and may help prevent cramping.
    • Sodium losses in sweat vary from 0.2 to 12.5 g/L.
  • Athletes should replace sodium losses:
    • Salty snacks, sports drinks, and broth-based soups can help.
  • Hyponatremia (low sodium levels):
    • Occurs when excess water dilutes sodium levels below 130 mmol/L.
    • Can lead to seizures, brain swelling, and death.

Fluid intake guidelines

  • Before training:
    • Prehydrate several hours before exercise.
    • Aim for USG <1.020 (indicating hydration).
  • During training:
    • Children (40 kg/88 lbs): drink 150 mL (5 oz) every 20 minutes.
    • Adolescents (60 kg/132 lbs): drink 250 mL (9 oz) every 20 minutes.
    • Adults: use individualized hydration plans.
    • During prolonged activity, consume 460-690 mg sodium/L, 78-195 mg potassium/L, and 5-10% carbohydrate solutions.
  • After training:
    • Replace fluid and electrolytes lost.
    • Consume 1.5 L (50 oz) per kg of body weight lost.
    • If fluid loss is >2% of body weight, increase sodium intake.

Water in the body

  • Composes 45-75% of body weight
  • Functions: lubrication, shock absorption, temperature regulation, nutrient transport, blood pressure maintenance
  • Essential for survival; only a few days possible without it

Fluid balance in athletes

  • Daily intake: Men 3.7 L, Women 2.7 L, Pregnant 3.0 L, Lactating 3.8 L
  • Athletes need more fluids due to sweat rate, environment, clothing/equipment
  • High sweat loss in sports (e.g., football linemen, basketball players: 1.6-3.5 L/game)

Preventing dehydration

  • 2% body weight loss from sweat impairs performance

  • Symptoms: increased core temp, heart rate, perceived exertion
  • Hydration assessment: USG, plasma osmolality (urine color unreliable)

Biomarkers of hydration status

  • Total body water: low practicality, acute/chronic, cutoff <2%
  • Plasma osmolality: medium practicality, acute/chronic, cutoff <290 mOsmol
  • Urine specific gravity: high practicality, chronic, cutoff <1.020 g/ml
  • Urine osmolality: high practicality, chronic, cutoff <700 mOsmol
  • Body weight: high practicality, acute/chronic, cutoff <1%

Electrolytes and performance

  • Sweat losses: mainly sodium chloride, minor potassium/magnesium/calcium
  • Sodium: retains fluid, prevents cramping, loss varies 0.2-12.5 g/L
  • Replace sodium: salty snacks, sports drinks, broth
  • Hyponatremia: sodium <130 mmol/L, risk of seizures, brain swelling, death

Fluid intake guidelines

  • Before training: prehydrate, aim for USG <1.020
  • During training:
    • Children (40 kg): 150 mL/20 min
    • Adolescents (60 kg): 250 mL/20 min
    • Adults: individualized plans
    • Prolonged activity: 460-690 mg sodium/L, 78-195 mg potassium/L, 5-10% carbohydrate solutions
  • After training:
    • Replace fluids/electrolytes
    • 1.5 L per kg body weight lost
    • If >2% weight lost, increase sodium intake

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Fluid and electrolytes

  • Water is the largest component of the body, making up 45-75% of body weight.
  • Functions of water:
    • Lubrication (joints, tissues)
    • Shock absorption (brain, spinal cord)
    • Body temperature regulation (cooling via sweat)
    • Nutrient transport and waste removal
    • Blood pressure maintenance
  • The body can’t survive more than a few days without water.

Fluid balance in athletes

  • Daily fluid intake recommendations (AI):
    • Men: 3.7 L (125.1 oz)
    • Women: 2.7 L (91.3 oz)
    • Pregnant women: 3.0 L
    • Lactating women: 3.8 L
  • Athletes may require more fluids, depending on:
    • Sweat rate
    • Environmental conditions (heat, humidity, altitude)
    • Clothing and equipment
  • Sweat loss and dehydration risk:
    • Linemen in football experience high sweat rates due to heavy gear.
    • Basketball players lose around 1.6-3.5 L (54.1-118.4 oz) per game.

Preventing dehydration

  • Dehydration risks:
    • Losing >2% of body weight from sweat impairs performance.
    • Symptoms include increased core temperature, heart rate, and perceived exertion.
  • Assessing hydration status:
    • Urine specific gravity (USG) and plasma osmolality are effective measures.
    • Urine color isn’t always reliable because vitamins and foods can change it.

Biomarkers of hydration status

Measure Practicality Validity (acute vs. chronic changes) EUH cutoff
Total body water Low Acute and chronic <2%
Plasma osmolality Medium Acute and chronic <290 mOsmol
Urine specific gravity High Chronic <1.020 g/ml
Urine osmolality High Chronic <700 mOsmol
Body weight High Acute and chronic <1%

Electrolytes and performance

  • Electrolytes lost in sweat:
    • Sodium chloride (NaCl) - most significant loss
    • Potassium, magnesium, calcium - minor losses
  • Sodium functions:
    • Helps retain fluid and may help prevent cramping.
    • Sodium losses in sweat vary from 0.2 to 12.5 g/L.
  • Athletes should replace sodium losses:
    • Salty snacks, sports drinks, and broth-based soups can help.
  • Hyponatremia (low sodium levels):
    • Occurs when excess water dilutes sodium levels below 130 mmol/L.
    • Can lead to seizures, brain swelling, and death.

Fluid intake guidelines

  • Before training:
    • Prehydrate several hours before exercise.
    • Aim for USG <1.020 (indicating hydration).
  • During training:
    • Children (40 kg/88 lbs): drink 150 mL (5 oz) every 20 minutes.
    • Adolescents (60 kg/132 lbs): drink 250 mL (9 oz) every 20 minutes.
    • Adults: use individualized hydration plans.
    • During prolonged activity, consume 460-690 mg sodium/L, 78-195 mg potassium/L, and 5-10% carbohydrate solutions.
  • After training:
    • Replace fluid and electrolytes lost.
    • Consume 1.5 L (50 oz) per kg of body weight lost.
    • If fluid loss is >2% of body weight, increase sodium intake.
Key points

Water in the body

  • Composes 45-75% of body weight
  • Functions: lubrication, shock absorption, temperature regulation, nutrient transport, blood pressure maintenance
  • Essential for survival; only a few days possible without it

Fluid balance in athletes

  • Daily intake: Men 3.7 L, Women 2.7 L, Pregnant 3.0 L, Lactating 3.8 L
  • Athletes need more fluids due to sweat rate, environment, clothing/equipment
  • High sweat loss in sports (e.g., football linemen, basketball players: 1.6-3.5 L/game)

Preventing dehydration

  • 2% body weight loss from sweat impairs performance

  • Symptoms: increased core temp, heart rate, perceived exertion
  • Hydration assessment: USG, plasma osmolality (urine color unreliable)

Biomarkers of hydration status

  • Total body water: low practicality, acute/chronic, cutoff <2%
  • Plasma osmolality: medium practicality, acute/chronic, cutoff <290 mOsmol
  • Urine specific gravity: high practicality, chronic, cutoff <1.020 g/ml
  • Urine osmolality: high practicality, chronic, cutoff <700 mOsmol
  • Body weight: high practicality, acute/chronic, cutoff <1%

Electrolytes and performance

  • Sweat losses: mainly sodium chloride, minor potassium/magnesium/calcium
  • Sodium: retains fluid, prevents cramping, loss varies 0.2-12.5 g/L
  • Replace sodium: salty snacks, sports drinks, broth
  • Hyponatremia: sodium <130 mmol/L, risk of seizures, brain swelling, death

Fluid intake guidelines

  • Before training: prehydrate, aim for USG <1.020
  • During training:
    • Children (40 kg): 150 mL/20 min
    • Adolescents (60 kg): 250 mL/20 min
    • Adults: individualized plans
    • Prolonged activity: 460-690 mg sodium/L, 78-195 mg potassium/L, 5-10% carbohydrate solutions
  • After training:
    • Replace fluids/electrolytes
    • 1.5 L per kg body weight lost
    • If >2% weight lost, increase sodium intake