Transcript Nutrition, Fitness & Sport

Nutrition, Fitness & Sport
Position Paper
of DC, ADA & Am.College Sports
Medicine
Joint Position Paper
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“…physical activity, athletic performance,
and recovery from exercise are enhanced by
optimal nutrition”
“…appropriate selection of food and fluids,
timing and intake, and supplement choices
for optimal health and exercise
performance”
Rodriguez, DiMarco, & Langley, 2009
Energy Needs
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What factors affect energy needs of
athletes?
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What sports might see weight cycling by
competitors?
Weight Loss and Physical
Activity
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Weight loss aims to reduce fat
Rapid weight loss
• lean tissue/muscle
• Fluid
• Increased chance of regain
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Is weight the only way body composition
changes are seen?
Body Composition
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Standards
• BMI 20-25
• % body fat – males 15-18%; females 20-25%
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Minimum level for health
• – males 5%; females 12%
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Why are body weight and weight for
height not good indicators of healthy
body size?
Body Composition
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Techniques to measure/estimate body
composition
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Hydrostatic (under water) weighing
Air displacement plethysmography
DEXA
Anthropomtric measures – skinfolds
Bioelectrical impedence
Hydrostatic Weighing
Air Displacement Plethysmography
DEXA
Skinfolds
Bioelectric Impedance
Energy Recommendations
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Accepted macronutrient
Distribution Ranges
• Recommended intakes of
energy-yielding nutrients
• CHO – 7-8 g/kg
• Pro – 1.2-1.4 g/kg
endurance
– 1.2-1.7 g/kg
strength
• Fat – 20-30%
Nutrients
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Do athletes require more protein than non-athletes?
• 0.8-1.2-1.5 g/kg
Which minerals are of primary concern with athletes?
Vitamins & Minerals
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Micronutrients of concern in athletes
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Calcium
Vitamin D
B vitamins
Iron
Zinc
Magnesium
Antioxidants
• Vitamins C & A, beta carotene, selenium
Hydration
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Important to athletes
• Heat production
• Affects muscle strength, endurance and
coordination
• Cramping, heat exhaustion and heat stroke
all of concern
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What conditions create dehydration risk?
Hydration
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How can one ensure
maximal hydration?
• 5-7 mL/kg 4 hr before
event
• Aim to prevent loss over
2% body wt
• Replace sweat losses
• 1-1.3 L/kg lost beginning
early after event
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Are specialized products
needed to ensure
adequate hydration?
Sodium (Na) in Sports Drinks
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Not needed, unless exercising strenuously
for more than 1 hour
• 600 mL bottle Gatorade contains ~275 mg
Na
• Daily Na limit 1500-2400 mg
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Not for refreshment or snack
Flavoured water better choice if plain
water not personally acceptable
Training Diet
2 fundamental differences between athlete’s
diet and general population?
 Pre-exercise meal (2-4 hr before event)
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• Sufficient fluid, low in fat and fibre, 200-300g CHO,
some protein, familiar foods
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During
• CHO in form of glucose 0.7 g/kg extends endurance
performance – every 15-20 min
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Post-game
• Depends on timing of next event
• Not needed if over 1 day until next intense workout
• CHO within 30 minutes
• 1-2 g/kg every 2 hr for 6 hr
• High GI foods replace glycogen losses better
Ergogenic Aids
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How should ergogenic aids be evaluated?
What are some of the ergogenic aids
currently marketed?
What types of effects have been proven
for these substances?
Nutritional Professional
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Career path:
• Undergraduate, internship, and work
experience
• Knowledge of exercise science and business
• At least 1-2 years employment in dietetics
• What roles does the nutrition professional
have in the area of sports nutrition?
Required Reading
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Lichtenstein, & Ludwig, 2010. Bringing back
home economics education.
 James, & Adams, 1998. Curriculum integration
in nutrition and mathematics.
 Graham, Beall, et al., 2005. Use of school
gardens in academic instruction.
 NS Dept. of Education & Health Promotion
and Protection. Food and nutrition policy for
Nova Scotia schools (web)