Nutrition for Exercise Flashcards
Name the 2 energy delivery systems.
Anaerobic and aerobic
Name the 2 energy systems involved in anaerobic energy delivery
Phosphate energy system
Lactate energy system
What substrate is used as fuel in the phosphocreatine energy system (anaerobic), and how long does that energy last?
Phosphocreatine
High intensity bursts up to 6 seconds
No waste products produced
What substrate is used as fuel in the lactate energy system (anaerobic), and how long does that energy last?
Stored muscle glycogen and serum glucose
Lasts up to 30 mins
Produces lactic acid as a byproduct
How long does it take for the body to remove lactic acid build up, after using the anaerobic lactate energy system?
Up to 2 hours
______________ is produced in the liver from glycine, arginine, methionine or is gained exogenously (i.e, from supplements.
Creatine
Creatine combines with __________ in muscle cells, to make phosphocreatine
Phosphate
Where is phosphocreatine stored and why?
In muscle cells, so it can be quickly used for maximum energy bursts.
Phosphocreatine creates energy when its phosphate-creatine bond is broken, and the phosphate is used to regenerate ADP into ATP. True or false?
True
Free creatine is recycled into phosphocreatine or is converted into __________ which is excreted in the urine.
Creatinine
In which energy system would you find the Cori Cycle?
The lactate energy system
(Anaerobic glycolytic system)
IN which organ does gluconeogenesis occur?
The liver
Which 3 mechanisms is energy produced via, in aerobic energy production?
Glycolysis
Citric acid cycle
Electron transport chain
What is used as fuel in aerobic energy production?
Primarily carbs and lipids.
Protein only under extreme conditions
Aerobic energy produces ATP + CO2 + ______
H20 (plus heat)
Aerobic energy systems are usually dominant up to ____% maximum heart rate.
80%
What is VO2 max?
Maximum oxygen uptake
Which type of exercise uses lipids as the main fuel? Give 2 examples.
Low intensity aerobic exercise
i.e, walking, yoga, pilates
Even when lipids are predominantly the main source of fuel, glucose is still used. True or false?
True
List 2 things that aerobic training increases.
Fat-oxidising enzymes, i.e, lipase
Number of capillaries supplying muscles
Number of mitochondria in muscle cells
Basal metabolic rate:
Female: BMR = kg body weight x ____ kCal
Male: BMR = kg body weight x _____ kcal
Female x 22 kCal
Male x 24 kCal
Red blood cells rely on _______ for energy
Glucose
The brain uses _______ and ________ _______ for energy
Glucose and ketone bodies
The liver primarily uses _______ ______ oxidation for energy
Fatty acid
Muscle cells use ____________, ____________ and __________ as energy sources
Fatty acids, glucose and amino acids
Cardiac muscle prefers ___________ and __________ as energy sources
Fatty acids and ketone bodies
Why are carbohydrates as a fuel source critical to performance and endurance?
They increase muscle and liver glycogen stores.
This allows longer energy production (both aerobic and anaerobic), longer sustained performance, and delayed exhaustion.
During extended moderate-high intensity exercise, a mix of glucose and fructose at a ratio of ___:1 should be used to maximise fuelling.
2:1
What is the purpose of carbohydrate loading?
To maximise glycogen stores, to increase performance and delay exhaustion.
Does carbohydrate loading increase power, strength or VO2 max?
No
When would you not recommend carbohydrate loading?
If there is insufficient exercise to use the extra glycogen
In which type of exercise event is carbohydrate loading useful?
Endurance events lasting longer than 90 minutes.
i.e, marathons, long distance cycling).
Why is it essential that athletes practice carb loading in advance of using it before an event?
There is huge individual variation in effectiveness and side effects.
List 5 important functions of protein in the body
Growth & maintenance of tissues
Enzymatic reactions
Act as messengers (protein hormones)
Provide structure (i.e, keratin, collagen)
Helps regulate blood pH (i.e, haemoglobin)
Balances fluids (i.e. albumin)
Boost immune health (i.e., immunoglobulins)
Nutrient transport and storage (i.e, ferritin)
Provides energy (4 kcal per gram)
The RDA daily protein requirement of 0.8 - 1.0g/kg is insufficient for athletes and people who regularly exercise. True or false?
True
List 4 things that affect protein requirements in athletes.
Individual requirements (height, weight, etc)
Exercise intensity
Exercise duration
Phases of the training
List 2 consequences of insufficient protein consumption in athletes / active people
Reduced performance
Suboptimal training and recovery
Lower immunity
Muscle catabolism
Pregnant athletes need an extra ___ g of protein per day in the 2nd and 3rd trimester.
10g
Ideal ratio of carbohydrate to protein is ____:1
4:1
When does the body revert to using lipids and protein for energy?
When glycogen stores are low
More ATP is produced per fatty acid molecule than per glucose molecule. True or false?
True
List 3 ways in which omega-3 intake positively impacts exercise performance
Increases delivery of oxygen and nutrients
Higher cell membrane flexibility
Improves release of growth hormone
Improves recovery
Enhances aerobic metabolism
Increases energy and stamina
Anti-inflammatory action
1 hour of moderate exercise in average environmental conditions, by the average athlete, can produce a body fluid loss of __ ___ of water
1 litre
List 3 symptoms of dehydration in athletes
Sluggishness, fatigue, headache, anorexia, light headedness, nausea
When might you add in a sports drink to exercise.
If exercising for over 1 hour
What usually causes hyponaturemia in athletes?
Too high water intake (flushes out sodium electrolytes)
Hyponaturemia caused by excess hydration has the same symptoms as dehydration. True or false?
True
Immune system suppression when cortisol secretions are high post exercise can last up to ___ hours
72 hours
Ingesting _________ during exercise can limit the release of cortisol levels by up to 80% in comparison to water
Glucose
What generally causes chronic inflammation in athletes?
Poor recovery
Why might acute inflammation be beneficial in athletes?
It is needed for tissue repair & remodelling
Aids adaptation to higher resilience
Aids hyperplasia and hypertrophy
Builds immune resilience
Why are antioxidants crucial for post exercise recovery?
To neutralise free radicals and regenerate tissue damage.
What is the concentration difference of potassium and sodium across cell membranes important for?
Nerve transmission
Muscle function
Why is iron critical for athletes?
Required for the formation of haemoglobin and myoglobin
Required by immune cells, bone homeostasis, DNA and neurotransmitter synthesis (all aspects of growth)
Which amino acid stimulates insulin release and can act as an insulin mimicker, shunting glucose and amino acids into muscle cells?
Taurine
Which amino acid can enhance protein metabolism and is anti-catabolic?
Taurine
Which amino acid is needed for the first step in the utilisation of medium and long chain fatty acids for energy (beta-oxidation)?
L-carnitine
Which protein is made from the 3 amino acids: glycine, arginine and methionine?
Creatine
List 2 food sources of creatine
Herring, salmon, tuna, beef, wild game
Adequate vitamin __ status may also be needed to optimise creatine uptake
Vitamin E
Which is the most abundant amino acid found in the muscles?
Glutamine
Name the 3 branched chain amino acids (BCAAs)
Leucine, isoleucine, valine
Large doses of BCAAs compete with tryptophan, tyrosine and phenylalanine for brain uptake, leading to decreased neurotransmitter synthesis. True or false?
True
Why can large doses of branched chain amino acids (BCAAs) be problematic?
They may compete with tryptophan, tyrosine and phenylalanine for brain uptake, leading to decreased neurotransmitter synthesis
List 4 commonly-used techniques in sports psychology.
- Arousal regulation
- Goal setting
- Imagery / visualisation
- Self-talk
