chapter 11: nutrition for physically active lifestyles Flashcards
physical activity
movement that results from skeletal muscle contraction
exercise
physical activities that are usually planned and structures for a purpose
physical fitness
ability to perform moderate-to-vigorous-intensities activities for a reasonable amount of time, without becoming excessively fatigued
healthy adults under 65 years of age should perform:
moderate intensity physical activity for at least ___ min a week
or
vigorous intensity physical activity for at least ___ min a week
and
____ exercises that focus on major muscle groups at least ___- a week
150
75
strength, twice
intensity
refers to the level of exertion used to perform an activity
intensity influenced by
duration and type of physical activity as well as body weight
methods of determining intensity include
physical signs such as breathing rate, ability to chat with others during the activity
use a percentage of your age-related max heart rate
calculate your age-related maximum heart rate
subtract age from 220
target heart rate zone
range of heart rate that reflects the intensity of exertion during physical activity
moderate intensity
target zone is 64-76% of age-related maximum heart rate
vigorous intensity
target zone is 77-93% of age related maximum heart rate
physical activity pyramid: top
sedentary activity
sitting, driving, watching TV, use a computer, texting, talking on the phone
physical activity pyramid: second from top
light recreational activity
2-3 days/week
bowling, walking, line dancing, doing yoga
physical activity pyramid: third from top
aerobic exercise (running, cycling, in line skating, stair stepping), flexibility exercise (stretching, lunges, toe touches, shoulder rolls), strength exercise (bicep curls, tricep presses, squats, lunges, push ups)
physical activity pyramid: bottom
activities of daily living
gardening, raking leaves, mowing the lawn, walking the dog, cleaning the house, playing with your children
aerobic exercise
physical activities that involve sustained, rhythmic contractions of large muscle groups
raise HR
aerobic exercise examples
running, jogging, rapid walking, swimming
strength exercise
activities that increase muscle mass and strength, can increase bone mass
flexibility exercise
activities that can improve the ROM of joints
cells obtain energy through a series of chemical reactions that breakdown
glucose, fatty acids, amino acids, alcohol
some of the energy stored within is captured in the high energy compound
ATP
ATP forms when
an inorganic phosphate groups bonds with ADP
glucose can be catabolized under conditions that are
anaerobic or aerobic
glucose catabolization involves
oxidation
first stage of glucose oxidation occurs under
anaerobic conditions
glycolysis anaerobic involves
breaking down a glucose molecule to form two pyruvate molecules
glycolysis: if oxygen is available
each pyruvate undergoes further oxidation in a stepwise series of chemical pathways
pyruvate moves from the cytoplasm into
mitochondria
in mitochondria, pyruvate is completely oxidized forming
ATP, CO2, H2O
primary source of direct energy for all cells
ATP
why is glucose a better fuel than fatty acids for intense, brief exercise
cells require more oxygen to metabolize fatty acids
during short, intense exercise, lungs and heart cannot deliver enough oxygen to muscles for them to use much fat for energy
three major energy systems
PCr-ATP system
lactic acid system
oxygen system
PCr-ATP system anaerobic or aerobic
anaerobic
lactic acid system anaerobic or aerobic
anaerobic
oxygen system anaerobic or aerobic
aerobic
PCr-ATP energy system
high energy compound used to reform ATP under anaerobic conditions
Per supplies energy to muscles for
10 seconds during intense events
jumping, lifting, throwing, sprinting
in anaerobic conditions, glucose is converted to pyruvate and then to
lactic acid, back to glucose
lactic acid: ATP formed can sustain
maximum physical exertion for 10-180 seconds
lactic acid is converted to
lactate
during lactic acid conversion, ___ form
hydrogen ions
most lactate enters the bloodstream, ___ removes it and converts it to
liver, glucose
during _____ exercise, muscle cells can completely metabolize glucose
low to moderate
oxygen energy system produces ____ more ATP than during anaerobic
18 times
aerobic system provides energy for
intense activities lasting 2 min or longer
when in use, example of activities: ATP
at all times
all types
when in use, example of activities:
PCr
all exercise initially, short bursts of exercise
shot put, high jump, bench press
when in use, example of activities:
anaerobic
high intensity training, 10-180 sec
100 meter dash
when in use, example of activities:
aerobic
2min-3hours, higher the intensity higher the use
basketball, swimming, jogging
when in use, example of activities:
fat
at rest
exercise lasting more than a few minutes
low to moderate intensity physical activity
sitting, 30 min brisk walk
when in use, example of activities:
protein
low amounts during all exercise
slightly more during endurance exercise especially when carb fuel is lacking
long-distance running
aerobic capacity
maximal oxygen intake during vigorous physical exertion
simple way to know when you are nearing your aerobic capacity
when you engage in vigorous exert to the point that you cannot carry on normal conversation
aerobic capacity can be increased by
engaging in an endurance training program that gradually increases the intensity level of activities
primary fuel when at rest or engaged in low to moderate intensity activities
fat
main fuel for high intensity activities
carbohydrate
___ contributes a small amount of energy with slightly more used during endurance exercise
protein
training influences the ratio of ____ that muscles use during endurance exercise
glucose to fatty acids
walking uses more fat or carbs
fat
weight lifting uses more fat or carbs
fat
2 hour run uses more fat or carbs
carb
hard cycling for an hour uses more fat or carbs
carb
championship basketball uses more fat or carbs
carbs
100-meter hurdles use more fat or carbs
fat
genetic endowment
inherited physical characteristics that can affect physical performance
factors that influence athletic performance
genetic endowment, mental and physical training, diet
sports nutrition
focuses on applying nutrition principles and research findings to improve athletic performance
males generally need at least ___kcal/kg/day
females need ____
50, 45-50
methods to determine if energy intake is adequate
record food intake
monitor body weight
fat should supply ____% of energy
20-35
to maintain adequate muscle glycogen and support moderate-to-vigorous-intensity activity for 1-3 hours athletes should consume ____g carb/kg/day
6-10
an athlete who weighs 80 kg (176lb) needs how many grams of carb per day
6x80=480
8x80=800
480-800 g/day
about 1-4 hours before an event lasting longer than 1 hour, eat a meal that
provides 1-4g of carb/kg BW
carbohydrate loading
practice of manipulating physical activity and dietary patterns 3-7 days before an event to increase muscle glycogen stores
increased muscle glycogen delays fatigue
during events lasting more than 90 mins
vigorous exercise lasting >60 mins depletes
glycogen stores
carbohydrate consumption during event recommendation
30-60g per hour of activity
avoid concentrated sources of fructose due to
potential for gastrointestinal upset
carbohydrate during exercise recovery goal
replenish muscle glycogen stores
carb for exercise recovery recommendation
6-12g/kg BW
post event meal sources
starchy foods
sources for quick glycogen replenishment
sports drinks, fruit, fruit juices
choc milk
athletes need ___g of protein/kg BW/day
1.4-2.0
protein sources
milk, other dairy, lean meat, dietary supplements that contain whey, casein, soy, egg protein
AI for water
young females: 11c/day
young males: 15.5c/day
water needs vary depending on
sport, fitness level, environmental conditions
heat cramps
heat related illness characterized by painful muscle contraction
earliest symptom of heat related illness
heat cramps
heat exhaustion
heat related illness that can occur after intense exercise in warm, humid conditions
heatstroke
most dangerous form of heat related illness and a medical emergency
heat exhaustion occurs especially when
fluid and salt intakes are inadequate
heat cramps signs and symptoms
painful muscle cramps, heavy sweating, tiredness, thirst
heat exhaustion signs and symptoms
dark urine, cool, moist skin, weakness, light headedness or dizziness, headache, nausea/vomiting
heatstroke signs and symptoms
dry, hot, red skin, fever, rapid, shallow breathing, confusion, irrational behavior, seizures, loss of consciousness
to reduce the risk of heat related illness
avoid exercising in extremely hot, humid conditions and replace fluid losses
to estimate the amount of fluid needed to replace water loss during exercise
weigh yourself before and after
drink _____ cups of water for each pound of body weight lost during exercise
2.5-3
sodium and other electrolytes found in sports drink help
maintain blood volume, enhance water and carbohydrate absorption, stimulate thirst
sports drinks are recommended when athletes
perform high intensity physical activity for >1 hour
oxidative stress may contribute to
muscle fatigue and damage
_____ may stimulate the body’s natural antioxidant defense system
intense exercise
iron is needed to
produce RBC, transport O2, obtain energy
___ deficiency can negatively affect athletic performance
iron
athletes at risk for iron deficiency include
females, distance runners, those who follow low calorie or vegetarian diets
sports anemia
temporary condition resulting from an increase in plasma rather than an iron deficiency
vegans and people who restrict intake of milk and dairy products can have
marginal or low calcium intakes
females who have irregular or no menstrual cycles may be deficient in
estrogen
weight bearing exercise increases bone density but ___ is needed to maintain healthy bones
estrogen
ergogenic acid
foods, devices, dietary supplements, or drugs used to improve physical performance
few ergogenic aids that have been shown to enhance performance
sufficient water and electrolytes, carbohydrates, balanced and varied diet
most widely used ergogenic aid
caffeine
caffeine benefits
raises blood fatty acid levels, enhances ability of skeletal and heart muscles to contract, increase mental alertness
caffeine adverse effects
shakiness and rapid heart rate, sleep disturbances, diarrhea and frequenct urination, potential withdrawal symptom
NCAA bans use of
caffeine
initiation stage time frame
first 3-6 weeks
incorporate short periods of physical activity into your daily routine
initiation stage
initiation stage goal
spend at least 150 mins in moderate-intensity activities each week
improvement stage time frame
next 5-6 months
begin improvement stage by
exercising at an intensity near the lower end of your target heart rate zone
maintenance stage time frame
end of improvement stage
maintenance stage
fitness goals reached, may not seem to be making further gains
warm up
5-10 mins, stretch, anticipated activity at low intensity
aerobic exercise type
exercise should increase heart and breathing rates and involve rhythmic movements of large muscle groups in the legs
aerobic workout duration
20-30 mins, 10-min intervals OK
aerobic workout frequency
number of times activity is performed per week, at least 5
aerobic workout intensity
moderate
aerobic intensity progression
gradual increase in the frequency, intensity and duration of exercise that occurs over a period
aerobic workout cool down
stretch 5-10 mins
strength training ___ days a week
at least 2
strength training: perform _____ exercises with ___ repetitions that strengthen ______
8-10
8-15
major muscle groups of upper and lower body
variety
activities with difference muscle groups
people who exercise regularly can reduce their risk of type two diabetes. true or false?
true
sports drinks are not useful for fluid replacement. true or false?
false
protein is the body’s preferred fuel for muscular activity. true or false?
false
heatstroke is a serious illness that requires immediate professional medical treatment. true or false?
true
while at rest, skeletal muscles metabolize more glucose than fat for energy. true or false?
false
