Sports nutrition Flashcards
Fitness def (2)
- ability to meet routine physical demands with enough energy to rise to challenge
- characteristics to enable body to perform physical activity
3 core recs of canada’s movement guidelines
- move more! including moderate, vigorous and light (standing) PA)
- reduce sedentary time
- sleep well!
Benefits of PA (11)
- physically (3)
- physiologically (5)
- mentally (2)
- general
- restful sleep
- nutritional health
- Improved body composition and healthy body weight
- improve bone density
- strong circulation and lung function
- resistance to cold/infectious disease
- low risk chronic disease
- reduced risk T2D
- low incidence of anxiety and depression
- strong self-image
- long life and high quality of life
Fitness will (increase/decrease) lean body mass and fat mass
- increase lean body mass
- decrease fat mass
Why will exercise reduce T2D risk? (2)
improves glucose tolerance + decreases blood pressure
Why will exercise reduce CVD and stroke risk? (2)
decrease serum lipids/cholesterol + decrease blood pressure
Why will exercise reduce osteoporosis risks?
resistance training = good for bone mass –> slows bone loss
Why will exercise reduce Alzheimer’s/dementia risk? through which pathway?
- slows cognitive decline/improve cognitive health
- through same pathway as CVD –> cardiometabolic profile, related to circulation and metabolism overall
FITT principle to achieve and maintain fitness?
Frequency: 3-5 sessions per week
Intensity: 50-90% of max HR
Time: min 30min
Type: resistance, endurance, flexibility
Resistance training
- what intensity?
- when?
- purpose (4)
- benefits (3)
- moderate
- 2-3 non-consecutive days/week
- build muscle mass, develop/maintain strength, power and endurance
- maximize and maintain bone mass + improve posture + reduce risk of back/hip injury
Endurance/cardiovascular training:
- how many times per week? how long
- benefits? (6 ish)
- 5-7 times per week, min 30min, moderate intensity
- improve heart and lung function: enhanced oxygen delivery + better cardiac output + slows heart rate + more efficient breathing + improved circulation + lowers blood pressure
Flexibility training:
- how many times per week
2-7 days per week
How does body responds to physical activity overload?
- responds by building structures to support activity
- developed through myokines –> proteins that signal changes in skeletal muscles/tissues/adipose tissue –> leads to physiological adaptation
Hypertrophy vs atrophy
(protein synthesis vs degradation)
hypertrophy: more synthesis than degradation –> gains muscles IF enough caloric intake
atrophy: more degradation than synthesis = weight loss
body size, shape and composition varies by (5)
age + sex + heredity + sport/event specific
Goal of nutrition in sports (5 elements to ans ish)
provide nutritional support to stay healthy and injury free, while maximizing metabolic adaptations to training and improving performance
3 energy systems of PA
used separately?
phosphagen + lactic acid + aerobic systems
- used all at the same time, to different degrees
Phosphagen system:
- uses what? –> stored where? lots of supply? does what?
- need O2?
- time duration?
- creatine phosphate –> stored in muscles, limited supply, allows to access ATP directly
- No!
- 5-10 sec
Lactic acid system:
- oxygen?
- time domain?
- __________ glycolysis
- No
- 20sec to 2min
- anaerobic
Anaerobic metabolism:
- sources of substrate? (2)
- what substrate enters? –> what does it do?
- Blood glucose OR glycogen stores (from muscle)
- glucose –> creates small amount of ATP (from creatine phosphate or lactic acid)
Lactate build-up during anaerobic metabolism:
- cori cycle?
- how long can activity be sustained for? why?
- recycling of lactate –> needs to leave muscle and travel to liver to be converted back into glucose
- 1-3min because accumulation > rate of clearing during high intensity activities
What causes muscle fatigue?
- lack of glucose/glycogen (+O2 part of if)
- NOT because of lactate build up
Aerobic system:
- needs O2?
- time domain?
- yes!
- 2min-20min –> ATP from carbs (glycolysis and TCA cycle)
- > 20 min –> ATP from fat (FA oxidation and TCA cycle)
Aerobic part of metabolism:
- what sources? (3)
- sources metabolized via what? complete burning of ___ to _____ and _____
- circulating glucose, muscle and liver glycogen and adipose tissue TG (glycerol)
- oxidative phosphorylation. burning of O2 to H2O and CO2
Aerobic activities stimulate (2) of mitochondria –> make then better/more effective at ?
- synthesis and enlargement
- aerobic metabolism/making ATP
carbs, FA, glycerol and prots/a.a
- yield energy?
- yield glucose?
- yield a.a and proteins&
- yield fat stores?
- all yield energy and fat stores
- FA cannot yield glucose VS a.a and glycerol can yield glucose if CHO unavailable VS CHO can yield glucose
- FA cannot yield a.a VS a.a and glycerol can yield nonessential aa when N available VS aa can yield aa
glycogen stores = _____ kcal = about _____ of running
2000 kcal
- 20 miles of running
Amount of stored glycogen depends on ?
diet. high carb diet = increase glycogen stores
beginning of activity, body uses (2) for fuel –> sustained aerobic activity, more _____ and less _____ used
- circulating glucose and glycogen
- fat and less glucose
after __-___ hours of strenuous activity (____% of VO2 max) –> need ___________
2-3 hours at 75%
- need gluconeogenesis
what are 3 physiological adaptations from training?
- trained athletes use glucose and glycogen slower/more efficiently
- increased number and size of mitochondria = better O2 efficiency
- body switches to fat more readily
when you use gluconeogenesis to max extent –> (3) –> leads to 3 symptoms
- hypoglycemia + depleted glycogen stores = halt nervous system function
- pins and needles feeling, shortness of breath, numbness
how to combat glucose depletion?
- eat high carb diet
- consume glucose during prolonged exercise (sports drink)
- carb rich food after activity
Carb rich foods after PA will increase (2)
- insulin sensitivity
- glycogen stores
carb recs for athletes
3-12 g/kg/day
fat recs for athletes
20-35% E –> same as general population –> take into account that athletes eat more calories
Protein recs for athletes
1.2-2.0 g/kg/day
protein = ___% of total fuel during activity and rest
10%
carbs and protein relationship to preserve lean tissue composition
- having enough carbs and energy will preserve lean tissue composition
- carbs are protein sparing
Why important to eat protein after exercise?
bc protein synthesis accelerates
what best way to distribute protein intake throughout the day?
20-30g of protein at 4-5 meals/snacks per day
Fluid losses vs how much can digestive system absorb
endurance athletes can lose up to 2L of water per hour VS digestive system can only absorb 1L/hour
Dehydration in sports causes (3)
- fatigue
- affects performance
- can lead to heat stroke (body can’t cool down bc too tired and no fluid)
Hyponatremia def
- caused by (2)
- leads to (3)
state of low blood sodium
- fluid loss OR drinking too much water
- shivers, dizsiness, loss of consciousness
sweat includes (3)
water + sodium + important electrolytes
Hydration recs during workout
- amount
- if <60min
- if >60min
- 125-250mL every 15min
- water
- water + 30-60g of CHO per hour (sports drink, fig bar)
caffeine;
- advantage
- disadvantage
- stimulant = can enhance performance
- can cause dehydration and fluid loss
vitamin and mineral supplements for athletes?
- won’t improve performance of well-nourished athletes –> will store or excrete excess
- can help with performance to prevent deficiencies that impede performance (especially for athletes trying to make weight classes)
how long does it take to vits and minerals to be assembled into their working larger units?
hours to days –> don’t take supplements 2 days before competition
how does iron deficiency impair physical performance?
low iron = low hemoglobin = inadequate delivery of O2 to tissue/cells
Sports anemia
- what?
- beneficial?
- permanent?
- oxygen carrying capacity altered?
- adaptive physiological response to PA –> loss of old blood cells + expansion of blood volume = iron levels low bc diluted
- beneficial!
- temporary
- nope
When increasing carb intake for athletes –> be mindful of ________
fiber!
Be mindful of what when fat intake
saturated fat –> risk factor for CVD even if super active –> negative metabolic effects
Plate distribution for:
- easy training/weight management
- moderate training
- hard training
VS health canada recs assumes you’re ?
- 1/2 f and v + a bit more than 1/4 prot and 1/6 carbs ish
- 1/3 of each
- 1/2 carbs, 1/4 prot, 1/4 f&v
- sedentary
pre-game meal should be (4)
high carb + moderate protein + low fat + low fiber
Post-even meal should be:
goal (2)
high carb, moderate protein, low fiber
- maintain muscle glycogen stores + increase muscle protein synthesis
important micronutrients for athletes (4)
vit E, Fe, Ca, vit D
True ergogenic aids (5)
convenient dietary supplements, caffeine, creatine, sodium bicarbonate, beta-alanine
