Mid-term Flashcards
recommended percentage of daily total kcals from carbohydrates?
woman should be between 225-300 grams and 300-375 grams for men
recommended percentage of daily total kcals from fats?
the average fat gram need for women(1) is 40-65 grams and 65-95 grams for men
UL
Tolerable Upper Intake Level
DRI
dietary reference intake
AI
Adequate Intake
EAR
Estimated Average Requirement
RDA
recommended daily allowance
monosaccharides
glucose
fructose sweetest
galactose
disaccharides
Sucrose
Maltose
Lactose
sucrose
glucose + fructose
table sugar
Maltose
glucose + glucose
found in some cereals
lactose
galactose + glucose
found in milk
Carbohydrate recommendation to encourage adequate glycogen storage in physically active males and females
4.5 g/kg per day
greatest fluid loss occurs where while dehydrated?
blood plasma
causes of dehydratoin
Diarrhea
Vomiting
Sweating
important body functions related to water
regulates body temperature, lubricates joints, carries oxygen and nutrients in blood plasma, helps dissolve minerals and make them available for the body, protects body organs and tissues, moistens tissues.
satiety
the quality or state of being fed
average stores of kcal stored in fat
Average male has 50,000 to 100,000 kcal of energy in fat
average store of glycogen in muscle and liver.
1-2 % by weight in muscle
8-10% in liver.
electrolytes
An electrolyte is a substance that conducts electricity when dissolved in water
why are electrolytes important?
because they regulate neural activity in the body and can lead to certain problems that can be harmful but are often not deadly unless chronic.
how do electrolytes affect fluid in the body
the water follows where the electrolytes are, more electrolytes = more water
hormones important in storage and use of carbohydrates and fats
insulin, leptin, ghrelin, glucagon
leptin
hunger suppressant
ghrelin
hunger inducing hormone
glucoagon
It works to raise the concentration of glucose and fat in the bloodstream
types of fat best to worst
monounsaturated
polyunsaturated
saturated
trans
unsaturated
Unsaturated fats, which are liquid at room temperature, are considered beneficial fats because they can improve blood cholesterol levels
saturated fats
Saturated fat is mainly found in animal foods increase HDL
transfats
made by heating liquid vegetable oils in the presence of hydrogen gas and a catalyst, a process called hydrogenation.
Glycemic index
a system that ranks foods on a scale from 1 to 100 based on their effect on blood-sugar levels.
What is the rationale and recommendation for CHO use during exercise?
start 30 min prior to fatigue
0.1-0.2 g/kg of body weight every 20 min.
Little evidence it improves performance under 1 hour
Something that would be digested fairly quickly
Liquid is better and more easily digested
What is the rationale and recommendation for CHO feedings immediately prior to exercise
30-15 min prior
Needs practice
● Conflicting studies
● Hypoglycemic individuals should avoid CHO intake 0-60 minutes prior to exercise
-This is magnified by high GI foods
Really depends other individual
What is the rationale and recommendation for CHO feedings immediately post exercise
- 0.75 - 1.5 g/kg every hour for first 4 hours (GI upset?)
Recommended percentage of daily total kcals from carbohydrates and fats
20-35% of energy from fat
55-60% from carbohydrates (5-10 g/kg/day)
6-8 g/kg for women
(8-10 g/kg) for men
RMR
resting metabolic rate
TEF
thermic effect of eating
factors affecting RMR
Body mass
Body composition
Age
Gender
Hormones
Nutritional supplements
Nicotine.
Pharmaceuticals
Prescription
Stress/emotional excitement
stress
Exercise
factors influencing TEF
temperature of environment, meal make up, activity level
recommendations of PA
150 minutes of moderate-intensity
or least 75 minutes of vigorous-intensity
benefits of PA
reduce your risk of a heart attack.
manage your weight better.
have a lower blood cholesterol level.
lower the risk of type 2 diabetes and some cancers.
have lower blood pressure.
have stronger bones, muscles and joints and lower the risk of osteoporosis.
obesity causes
Behavior Physical Activity diet Community Environment Genetics Diseases and Drugs
recommended fat percentage for men and woman
Recommended amount for woman 20% - 25% ; for men 8% - 14%
essential amount of fat
woman 10-13% men 2-5%
health related effects of obiesty
Heart disease and stroke. High blood pressure. Diabetes. Some cancers. Gallbladder disease and gallstones. Osteoarthritis. Gout. Breathing problems, such as sleep apnea
ATP-PC
Substrate: Creatine kinases
Duration: 2-10 sec
End product: ADP Creatine
Efficiency: 28%
Location: Cytoplasm
Glycolysis
Substrate: glucose
Rate limt factor: Phosphofructokinase, PFK
Duration: 10-20 sec
End product: 2 ATP pryuvate/lactate
NADH
Efficiency: Low 30%
Location: Cytoplasm
Glycogenolysis
Substrate: pyruvate
Rate limt factor: Phosphofructokinase, PFK
Duration: 40 sec -2 min
End product: 2 ATP pryuvate/lactate
NADH
Efficiency: mid 30%
Location: Cytoplasm/Liver
Kreb Cycle
Substrate: Pyruvate/ Actal-coA
rate limit factor:
Isocitrate drogenase
Duration: 2 min+
End product: 3 NADH, 1FAD 1 ATP
Efficiency: 45
Location: Mitochondria
Electron transport system
Substrate: NADH, FADH
Rate limiting factor: Cytochrome Oxidase
Duration: 2 min +
End product: 36 ATP , H20
Efficiency: 45%
Location: mitochondria
Glouconeogenisis
Substrate: keytones
Duration: 2min +
End product: 3 NADH, 1FAD 1 ATP
Efficiency:45%
Location: liver
How does endurance training improve fat burning capacity physiologically?
Exercise training ↑ ability to work harder, longer, at a low VO2
↑ mitochondrial content & # of enzymes within mito.
↑ concentration
↑ MT-LPL, &
fatty acyl-CoA
↑ muscle TG storage & oxidation
↑ capillary density ↑ blood flow
↑ HSL
↑ cardiovascular & respiratory system that ↑ O2 delivery to muscle for fat oxidation (↑ capillarization)
Pre-game meal rationale and recommendations
● Provide adequate hydration
● Takes 4-6 h to digest a meal completely
- Recommendation is 2-6 h prior to competition
- Allow full diaphragm expansion
● Provide carbohydrates to “top off” liver stores
● Avoid the sensation of hunger
● Minimize GI tract problems
- Small & easily digested
- Familiar to individual
● High in carbohydrate
- ~200-300 g (~500-1200 kcal)
- 4-5 g/kg of body weight
● Low in fat & fiber
● Moderate in size
- Depends on size of athlete &
nature of sport
● Athletes engaging in early AM activities may want to schedule a very early morning (2:30-4:30 AM) snack or CHO drink
● Always take individuality into consideration
Why or why not would CHO use during exercise help recreational athletes that workout 4-10 hours/wk.?
It depends on intensity and duration
if an individual is exercising for over 90 may be important to replenish CHO store
prevention of gluconeogenins
Glycogen depletion can occur after 2-3 hours of continuous exercise at 60-80% max VO 2 or after intermittent 90-130% of max VO 2
If not there is really no need
evidence dose not support <1 improvement during exercise
What are the recommendations for hydration pre, during, and post exercise longer than 1 hour?
● 1-2 hours before - ~500 ml (16 oz) of water in a 4-8% CHO solution
● 15-30 minutes before 300-500 ml (10-16 oz) of water in a 4-8% CHO solution
● Drink ~250 ml (6-8 oz) of water with 4-8% CHO every 10-15 min
-Na & Cl may help depending on osmolality
● Recovery - immediately & every 2 hours, 1g of CHO/kg of body weight, fluid to replace body losses: 500•0.5kg lost ( or 2 c•lb lost)
Fat mobilization and utilization during exercise. What does the research say in regards to fat feeding and mobilization during exercise? Does it spare glycogen stores? Why or why not?
Evidence dose not support fat as an ergogenic aid
Dose not have an effect on glycogen stores
fat burning capability is based on athletic training, duration, & intensity not amount
6 key strategies for successful weight control.
- engaging in high levels of physical activity
- eating a diet that is low in calories and fat;
- eating breakfast
- self-monitoring
- weight on a regular basis
- maintaining a consistent eating pattern
- catching “slips” before they become habits
Based on the research (mention specific studies) presented in class, what arguments could you make that obesity is caused more by lifestyle than genetics?
Major differences in the tendency of individuals toward obesity
25% of variability is due to genetic factors
30% of variability is due to cultural factors
Twin study
What is the physiological rationale and specific nutritional recommendation for carbohydrate use during exercise, over 1 hour, under 1 hour
- 0.1-0.2 g/kg of body weight (0.05-0.1 g/lb ) every 20 min.
- Starting 30 minutes before fatigue
- initiated 30 minutes into exercise
Something that would be digested fairly quickly
ex: Glucose, sucrose, maltodextrin, etc….
How might CHO loading help athletes? Why and when is it appropriate?
● Muscle glycogen loading
(“supercompensation”)
-Goal is to maximize muscle glycogen
● Normal glycogen levels
-Trained male athlete on mixed diet are
~130-160 mmol/kg of muscle
-Untrained male ~80-100 mmol/kg of muscle
-Super Compensated male ~200 mmol/kg of muscle
Used for individuals preparing to be exhausting
In exercise lasting 2-4 hours, how does the use of glucose and lipids change in skeletal muscle during moderate intensity endurance exercise (70% VO2max)? How do blood concentrations of energy substrates change
Long duration type of exercise utilizes more lipids rather than blood glucose.
if not adequately fed gluconeogenosous occurs and utilizes keytones (protein) for energy along side fat
