Ch 12: Nutrient Timing Flashcards
The temporal positioning of nutrients throughout the day and/or relative to the exercise bout in order to maximize performance or improve body composition
Nutrient Timing
Metabolic Pathways
ATP-PC Pathway, Glycolytic System and Oxidative System
Energy System that only lasts 10 seconds
ATP-PC Pathway (Adenosine Triphosphate and Phosphocreatine
Breakdown of Glucose into ATP. Lasts 60 seconds and is Anaerobic
Glycolysis
Primary source of ATP when at rest or low intensity, longer duration exercise
Oxidative Energy System. Requires Oxygen to make ATP. 60 minutes or longer. Breakdown of Carbohydrates and Fat
The Brain uses what percentage of glucose-derived energy
20%
Characteristics of Fiber
Found in Carbohydrates. Plays vital role in how quick something is digested and used as energy. Resistant to digestion in the Small Intestine
Timing of Fiber intake
Meals further away from activity should be higher in fiber compared to the meals or snacks closer to activity (1 to 2 hours before) so food has time to digest and be available for energy
Recommended amount of Protein
Ranges from 10 - 35% of total energy
General RDA for Protein
0.8 gram/kilogram/day Nonactive
Active: 1.2 - 1.6 1.6 gram/kilogram/day
Most abundant source of Endogenous energy in the body, due to their high energy capacity as well as copious amount of storage
Fatty Acids
Roles of Fat
Nutrient Absorption, Hormone Regulation, Heart Health, Blood Pressure Regulation, Protection of Vital Organs and Hair and Skin Health
Group of Lipids that are Esters formed from one molecule of Glycerol and three molecules of one or more fatty acids, stored within the muscle
Intramuscular Triglycerides - accessed for energy while training. Must be replenished during long duration training
A Molecule that is acted upon by an enzyme
Substrate
Stored Energy
Glycogen
Body stores of Glycogen
Enough Glycogen for 90 - 120 minutes of Endurance exercise
When body begins to convert other forms of stored energy (fats and lean tissue)
After 60 minutes of continuous exercise
Adequately fueled body can store how long of continuous exercise
Up to 120 minutes
Estimated Energy Stores: ATP-PC in Various Tissues
5 kcal
Estimated Energy Stores: Carbohydrate in Blood Glucose
80 kcal
Estimated Energy Stores: Carbohydrate in Liver Glycogen
400 kcal
Estimated Energy Stores: Carbohydrate in Muscle Glycogen
1500 kcal
Estimated Energy Stores: Fat in Free Fatty Acids
7 kcal
Estimated Energy Stores: Fat in Serum Triglycerides
75 kcal
Estimated Energy Stores: Fat in Muscle Triglycerides
2500 kcal
Estimated Energy Stores: Fat in Adipose Tissues
80000 + kcal
Estimated Energy Stores: Muscle Protein
30000 kcal
Main substrates for high endurance activity
Carbohydrates (moderate to high intensity) and Fat (Lower-intensity activity)
- As exercise duration continues (prolonged bouts of exercise), fuel substrates begin to shift, moving more from carbohydrates (glycogen) to fat stores
Amount of carbohydrates an endurance athlete should have depends on what?
Size, Gender, Training Program and Sport
Carbohydrate amount for high endurance athletes
8 to 12 grams/kilograms/day
Pre-exercise meal fueling strategies for Endurance athletes: 3-4 hours before exercise
High in quality Carbohydrates
Lean Protein
Low in Fiber and Fat
Pre-exercise Hydration Endurance athletes:
4 hours before activity
Pre-exercise snack fueling strategies for Endurance athletes:
30 minutes to 1 hour before exercise
High in Carbohydrates
Moderate in Protein
Low in Fat and Protein
Peri-exercise snack fueling strategies for Endurance athletes:
Carbohydrate intake should begin shortly after onset of activity, but only if the exercise session is continuous and will last more than 60 minutes.
Pre-exercise Hydration strategies for Endurance athletes:
Continue Hydrating (ex 5 - 10 oz of water)
Peri-exercise hydration strategies for Endurance athletes:
Continue hydrating, which is dependent on the athlete’s sweat rate.
Example: 0.4 to 0.8 liters per hour
Sports drinks should contain 6 to 8% carbohydrate solution.
Replace electrolytes lost with sports drinks or foods high in sodium and potassium.
Post-exercise hydration strategies for Endurance athletes:
Continue hydrating.
Example: Drink 16 to 24 oz water or sports drink for every pound lost during exercise (1.25 to 1.5 liter per kilogram of body weight lost during exercise).
Post-exercise snack fueling strategies for Endurance athletes:
Critical only if another exercise bout is planned within 24 hours; however, no harm in replenishment soon after exercise
2 hours after exercise (Continue meals in 2-hour intervals up to 6 hours.)
Quality carbohydrate and lean protein
Carbohydrates: 1 to 1.2 g/kg per hour for 4 to 6 hours post-exercise
Protein: 0.25 to 0.3 g/kg post-exercise
What does Resistance Exercise Stimulate
Muscle Protein Synthesis (MPS)stimulated and augmented by protein ingestion (Muscle Hypertrophy)
Factors in Muscle Hypertrophy
Properly designed and Simultaneous resistance-training program. Hormone Levels, Total energy and Protein
Fueling Strategies - Strength Athletes: Pre- Exercise Meal
2 - 4 hours before exercise; High in quality Carbs (1 - 4 g/kg)
20 - 30 g lean protein
Low in Fiber and Fat
Start Hydration 4 h before
Fueling Strategies - Strength Athletes: Pre- Exercise Snack
High in carbs
Mod in Protein
Low in Fiber and Fat
Cont Hydrating (5 - 10 oz)
Fueling Strategies - Strength Athletes: Peri-Exercise Snack
30 to 60 g carbohydrates per hour spaced every 15 to 20 minutes for exercise lasting over an hour
Continue hydrating, which is dependent on the athlete’s sweat rate.
Fueling Strategies - Strength Athletes: Post-Exercise Meal/Snack
Critical only if exercising again within 24 hours, but not harmful to try to consume quality carbohydrates and protein soon after exercise session comes to an end and at repeated intervals (about every 4 hours), particularly when it comes to protein
Quality carbohydrates and lean protein
Carbohydrates: 1 to 1.2 g/kg for 4 to 6 hours post-exercise
Protein: 20 to 30 g (0.25 to 0.3 g/kg) consumed after exercise
Cont Hydrating
Commonality in diet to simultaneously lose body fat and gain muscle
Quality and Quantity of Protein
Increasing protein intake while in a negative energy balance can help preserve muscle.
What is essential for a weight increase or reduction plan
High-quality Protein, whole grain carbohydrates and Healthy fats
Time it takes to digest Carbohydrates
1 - 2 Hours
Time it takes to digest Protein
3 - 4 Hours
Time it takes to digest Fats
Up to 6 Hours
Manipulating Carbohydrate intake on a day-to-day or even a meal-by-meal basis
Carbohydrate Periodization (Low- to Moderate- to High-carbohydrate meals are used to alter the availability of Glucose in a preceding training session
The same number of calories
Isocaloric
Waking up in the morning and exercising in a fasted state
Fasted Training
A client restricts carbohydrates in the post-exercise period with the intention of enhancing pathways for fatty-acid oxidation
Recover Low
In this method, athletes perform an evening training session, restrict carbohydrates during overnight recovery, and then complete a fasted training session the following morning. The total time with reduced muscle glycogen is between 12 to 14 hours. Using this technique for 1 to 3 weeks showed improved endurance efficiency.
Sleep Low, Train Low
Athletes complete a morning session to deplete muscle glycogen and follow the day up with a reduced carbohydrate intake, so the second exercise session is with reduced muscle glycogen.
Twice-A-Day Training
A period of time following exercise in which nutrients such as protein and carbohydrates can be used to maximize muscle growth and Glycogen replenishment
Anabolic Window
Anabolic Window timing
30 to 45 minutes after exercise
1 - 2 hours post exercise is when Protein Synthesis happens most effectively
Total amount of protein and carbohydrates eaten over the course of the day is more important for body composition and performance than nutrient-timing strategies specific to the workout itself
Breakfast consumption benefits
Improvement in Behavior, Cognition, Concentration and school performance in children
Quality in the overall diet, micronutrient intake, Bodyweight and other lifestyle factors
Maximal Effect for Carbohydrate Timing
Continuous exercise > 60 minutes
Repeat bouts of exercise (training or competition) within 24 hours
Maximal Effect for Protein Timing
Timing around exercise in a fasted state or if previous meal was > 3 hours prior
When is the timing of meals important?
Individual’s goal includes extreme muscle or strength gains, extreme fat loss in advanced exercisers and continuous and exhaustive training lasting over 60 min or more
Increased Strength and Muscle Mass
Carbohydrates, Protein and Creatine taken around the activity session
Glycogen stores during exercise
90 - 120 minutes
Sleep Low, Train Slow Carbohydrate Periodization Method
Athletes perform an evening training session, restrict carbohydrates during overnight recovery and then then complete a fasting workout in the morning
Strength athletes pre-workout meal timing
2 - 4 hours prior to exercise
Pre-exercise snack timing before endurance exercise activity
30 min to 1 hour
