1. Nutrition and Physical Activity
Chapter 13

2. Fitness Depends on physical activity and exercise (not body type!)
Regular physical activity
Promotes health
Reduces risk of developing many diseases
Heart disease
Cancer
Stroke
Diabetes
Hypertension

3. More Benefits of Fitness
Restful sleep
Nutritional health
Optimal body composition
Optimal bone density
Resistance to infectious diseases
Lower incidence of anxiety & depression
Lower risk for some types of cancer
Strong circulation & lung function
Stress reduction
Cortisol reduction
Strong self image
Lower risk of dementia

4. How much should I do? Highly individual
Just min/day starts to reduce disease risk
Minimum for optimal health: 2.5 hrs moderate or 1.25 hrs vigorous activity
Not an upper limit!
Good to spread out over the week
How much is too much?

5. Developing Fitness Minimizing risk of overuse injuries
Be active all week
Use proper equipment and attire
Use proper form
Include warm-up and cool-down activities
Challenge your strength and endurance a few times a week
Mix it up!
Pay attention to body signals

6. Developing Fitness Muscle conditioning Balanced fitness program
Fit muscles use oxygen efficiently
Increased mitochondria and vasculature
Reduces heart’s workload
Burns fat longer
Balanced fitness program
Activities you enjoy doing
Addresses all aspects of fitness
Strength, endurance, flexibility
Each has specific benefits

7. Resistance Training Purpose
Build muscle mass
Increases metabolism!
Develop and maintain muscle strength, muscle power, and muscle endurance
Benefits for prevention of chronic diseases
Maximizes and maintains bone mass
Improves posture & reduces risk of back injury

8. Nutrition & Physical Performance
Performance and recovery both enhanced by optimal nutrition
We need all essential nutrients to power movement
3 energy systems:
ATP-CP, lactic acid, and oxygen
All 3 systems always active and work together
ATP-CP (creatine phosphate)
Stores of ATP and CP only power muscles 3-15 seconds
Muscle and liver glycogen needed to continue contraction

9. Creatine Phosphate Popular supplement (ergogenic aid)
Studies show improvement in muscle strength and power
No benefit for aerobic training
Possible side effects:
Weight gain (water retention)
GI symptoms: nausea, diarrhea, abdominal pain
Rash, anxiety, headache, fatigue
Not appropriate for people with kidney issues
Should be avoided in children, adolescents, pregnant women, nursing mothers, diabetics

10. Anaerobic vs. Aerobic Anaerobic activities and fatigue
Lactic acid energy system
Anaerobic glycolysis leads to drop in pH
Impairs glycolysis, inhibits binding of calcium
Aerobic activities and endurance
Oxygen energy system
Oxidative metabolism of energy nutrients
Increased blood flow to muscles: oxygen!
Produces much more ATP, but at slower rate
Uses glucose and fatty acids

11. Endurance
As long as ATP supply meets energy needs, activity can continue
Rate/intensity of activity influences energy system used
Anaerobic exercise: CP and glycogen rapidly depleted
Level of training highly influences shift to anaerobic metabolism
Number of mitochondria and efficiency of oxygen delivery increase with training

12. Glucose Use During PA
Exertion
Liver breaks down glycogen
Release glucose into bloodstream
Muscles use glucose and stored glycogen
Muscle fatigue when glycogen is depleted
Glycogen storage: limited
Intensity of activity
Impacts how long glycogen will last
CHO post-workout restores glycogen, spares muscle tissue

13. Protein Use & PA
Not a significant part of fuel mix for most
Used in muscle building
Synthesis suppressed during activity; accelerates afterward
High-quality protein consumption
Enhances muscle protein synthesis
What is a high-quality protein?
Protein needs are higher for endurance and strength athletes
Need adequate CHO, as well…why?

14. Recommended Protein Intakes for Athletes
Endurance athlete: g/kg body weight
Strength athlete: g/kg body weight
Everyday adults: minimum of 0.8 g/kg body weight
Max. usable amount for adults: 2.0 g/kg body weight
Risks of excessive protein intake
Dehydration
Mineral losses

15. Vitamins and Minerals to Support Activity
Roles in supporting activity
Assist in releasing energy from fuels
Transport of oxygen
Multiple vitamins and minerals, as well as protein, involved!
Supplements
Vast majority do not enhance performance of well-nourished people

16. Fluids and Electrolytes to Support Activity
Fluid replacement via hydration
Hydrate before activity
Drink extra fluid in the days before event
Rehydrate during and after activity
Fluids for everyday, active people
Plain, cool water
Fluids for endurance athletes
May benefit from mineral and CHO-containing beverages

17. Sports Drinks vs. Water Sport drinks offer the following Sports drinks
Hydration is critical to optimal performance
Water is best for most people
Sport drinks offer the following
Fluid
Glucose
Sodium and other electrolytes
Some prefer the flavor

18. Dietary Strategies for Active People
Hydrate
Thirst is a late signal of need
Choose nutrient-dense foods
Vitamins & minerals
Consume adequate energy
Need all energy-yielding nutrients
CHO, protein, and fat
Meal frequency and balance
Stable blood glucose means stable energy levels
Optimal maintenance of lean tissues

19. Timing of Meals 30 min-1 hour pre-workout During workout Post-workout
Protein-based snack or small meal
Timing is individual
Not for everyone! Depends on GI picture.
During workout
Sip water
Post-workout
Best time to consume CHO-rich foods
Include protein! Balance.
Fitness goals: highly individual!
Timing strategies vary depending on goal
Ex: carbohydrate loading