Week 1 - Physical Activity, Fitness, Exercise & Sedentary Behaviour + Nutrition Flashcards
Define physical activity
Any bodily movement produced by skeletal muscles that requires energy expenditure
Define exercise
Physical activity that is planned, structured, repetitive and designed to sustain or improve health or fitness
Define physical fitness
Ability to carry out daily tasks with vigour and alertness, without undue fatigue, to enjoy leisure pursuits, to meet unforeseen emergencies, and resist hypokinetic diseases
Define physical inactivity
Doing insufficient moderate-vigorous physical activity to meet guidelines (or to maintain health)
Define sedentary behaviour
Any waking behaviour characterised by an energy expenditure <1.5 metabolic equivalents of tasks (METs), while in a sitting, reclining, or lying posture
Describe some key features of adult physical activity guidelines
- At least 150 minutes of moderate intensity activity per week OR at least 75 minutes of vigorous activity (or a combination of both)
- Strength building at least 2 days a week
- Minimise sedentary time
- For older adults: improve balance 2 days a week
Describe some key features of children physical activity guidelines
- 180 minutes/day for 1-5y/o
- 60 minutes/day for 6-18y/o
- Under 1 years, 30 minutes across the day of tummy time
What are the levels of physical activity intensity and how can they be described?
- Sedentary: sitting or lying with little movement and a low energy requirement
- Light: aerobic activity with no noticeable change in RR, can be sustained for at least 60 minutes
- Moderate: aerobic that can be maintained for 30-60 minutes, whilst holding a conversation uninterrupted
- Vigorous: aerobic activity lasting up to 30 minutes, where conversation generally cannot be maintained uninterrupted
- High: activity that cannot be sustained for longer than 10 minutes
What is a MET
MET = Metabolic Equivalents of Task
- 1 MET = resting energy expenditure (energy you use when you’re resting)
- Can describe physical activity or exercise in terms of METS i.e. as multiples of resting energy expenditure
What are some typical MET requirements of day-to-day activities and positions?
- Sedentary (<1.6 METs): low energy requirement <40% HR (sleeping, sitting, riding a car, watching TV)
- Light (1.6-3 METs): 40-55% HR (leisure walking, playing cards, cooking activities, light chores, yoga)
- Moderate (3-6 METS): 55-70% HR (walking briskly, vacuuming, mowing lawn, table tennis)
- Vigorous (6-9 METS): 70-90% HR (stationary rowing, jogging, running, carrying heavy upstairs, rock climbing)
- High: >90% HR (running, sprinting, water polo)
What are some examples of grains and the nutritional benefit they provide?
Examples: rice, bread, cereals, pasta
Benefits: complex carbohydrate (CHO), fibre, energy
What are some examples of dairy and the nutritional benefit they provide?
Examples: yoghurt, milk, cheese
Benefits: CHO, protein, fat and vitamins and minerals
What are the macronutrient proportions for an inactive person?
CHO: 45%
Protein: 25%
Fat: 30%
What are the macronutrient proportions for a healthy (active) person?
CHO: 65%
Protein: 15%
Fat: 20%
What are the macronutrient proportions for an elite endurance person?
CHO: 60%
Protein: 20%
Fat: 20%
What are the type of CHOs and give an example of each
- Monosaccharides: glucose, fructose
- Disaccharides: lactose, maltose, sucrose
- Polysaccharides: starch, fibre (non-starch), glycogen
What is the role of CHOs in exercise?
- Primary energy source for the CNS (brain) and high intensity physical activity
- Metabolic primer for fat use
- Adequate CHO spares protein use
What is glycemic index (GI)?
The index of effect of CHO ingestion and insulin secretion
A scale that ranks a CHO-containing food or drink by how much it raises blood sugar levels after it is consumed
What do high GI foods do in the body? Give at least 3 effects
- Increase insulin secretion
- Increase glucose uptake and use
- Increase lactate production
- Inhibit lipolysis
- Increase the rate of glycogen depletion
Name some high GI foods
- Glucose
- Carrots
- Honey
- Corn flakes
- Whole meal bread
- White rice
- Brown rice
- Sultanas
- Bananas
Name some low GI foods
- Apples
- Fish sticks
- Butter beans
- Kidney beans
- Lentils
- Fructose
- Peanuts
What are the 3 main roles of amino acids?
- Major structural components of tissues
- Major regulatory chemicals
- Provide creatine for creatine phosphate
What are the guidelines for protein intake post exercise?
- 15-25g (0.21-0.3g) protein 0-2 post exercise for optimal muscle protein synthesis and increased strength and muscle mass
- 0.3g/kg protein after exercise and 3-5 hours over multiple meals
- Protein (casein) immediately before sleep for overnight recovery
What type of protein is considered the best and why?
Milk/dairy protein, chicken and fish. Due to leucine content and digestion/absorption kinetics of BCAAs
What is the whey to casein ratio in dairy protein?
20% whey + 80% casein
What are the types of fats?
- Saturated (single bonds): butter, cake, cheese, biscuit, bacon
- Unsaturated (double bonds, liquid at room temperature): peanut butter, avocado, fatty fish, nuts & seeds
What are the roles of fats?
- Main energy reserve
- Primary energy source during low-moderate intensity activity
- Component of cell membranes
- Component of hormones and other cell regulators
- Provides satiation
- Major vitamin carriers (A, D, E, K)
If someone is on a low fat diet, what vitamin and mineral deficiencies may they display?
Fe, Mg, Ca, Zn, Folic acid, Vitamin A, D, E and K
How much of body mass of males and females is fat?
Males ~ 15%
Females ~ 25%
Where is fat stored?
Mostly in adipose tissue, small amounts in muscle and plasma
Name the fat soluble vitamins
A, D, E, K
Name the water soluble vitamins
8x B vitamins, vitamin C
What are the 7 major minerals?
Ca, Mg, Na, K, P, S, Cl
What do antioxidants do in the body?
Protect cell membranes, prevent or reduce the damage caused by oxidation
What are the recommendations for fluid intake for athletes?
- 2-2.5L/day
- 5-10mL/kg in the 2-4 hours pre-exercise
- 0.4-0.8L/h during exercise
- Sports drinks not required until exercise is longer than 1 hour or there is excessive sweat loss
What are some problems with supplements
- Product labels often inaccurate
- Lack of quality research
- Many have unpleasant side effects
- May contain banned substances for competition
- Difficult to establish safety due to multitude of ingredients
What are some benefits of protein supplements for athletes?
- Post exercise recovery
- To increase lean muscle mass
- Portable nutrition
What are benefits of amino acid supplements for athletes?
- May be an energy source for endurance athletes
- May enhance lean mass with resistance training
What is the benefit of creatine supplements for athletes?
Positive effects on acute high intensity exercise, which in long term improve lean mass gains and muscular strength and powder
What are the two main goals of nutrition before and during exercise?
- Prevent dehydration
- Assist energy provision with CHO intake
At what duration of exercise would you need higher CHO intake?
> 1 hour
What are two disadvantages of high CHO intake during pre-comp nutrition?
- Increased water weight
- May cause diarrhoea
What are the three competition fuelling strategies and when would you use them?
- Carb loading for >90 minutes of exercise
- Pre-event fuelling for >60 minutes of exercise
- Quick-refuelling for when there is <8 hours recovery between two sessions
What are the two goals of nutrition during exercise?
- Maintain blood glucose
- Delay glycogen depletion (tired, fatigue, exercise performance will suffer)
What are some palatability influences on intake during exercise?
- Flavouring
- Concentration of substances
- Presence of electrolytes
- Temperature of drink
What are some upper GIT symptoms someone may experience with exercise?
- Nausea
- Vomiting
- Belching (burp)
- Heartburn
- Chest pain
What are some lower GIT symptoms someone may experience with exercise?
More common with running, influenced by intensity of exercise
- Bloating
- GI cramps
- Flatulence (farting)
- Urge to defecate
- Diarrhoea
What are some factors that may increase upper GIT symptoms during exercise?
- Diet high in fibre, fat and protein
- Hypertonic drinks
- Dehydration
- Exercise intensity
What are the five main influences on gastric emptying rate during exercise? What are their influences?
- Volume: higher volume = higher emptying rate
- Temperature: colder fluids empty slightly faster
- Carbonation: slows rate of gastric emptying and ∴ delays water and CHO absorption
- Osmolality: high osmolality (hypertonic) slows emptying.
- Intensity of exercise: little effect with intensities up to ~75% max. but gastric emptying slows at higher intensities
What are the 3 ways CHOs are absorbed?
- Passive diffusion
- Facilitated/carrier mediates
- Active
How is water absorbed in the body?
By diffusion with osmotic gradients. Mostly in small intestine
How is sodium transported into
a) Epithelial cells
b) Interstitial fluid
a) Diffuses or co-transports
b) Active
What are 3 main influences on absorption from GIT during exercise?
- Osmolality - hypotonic to isotonic best
- CHO content - low moderate concentrations absorbed faster
- Sodium - low moderate concentrations increase water and glucose absorption
What are the 3 main considerations for solutions consumed during exercise and why?
- Fluid content (hydration) - blood volume/flow and thermoregulation
- CHO content (energy) - slows glycogen depletion
- Electrolyte composition - restore
What are the 4 goals of nutrition recovery spot exercise?
- Replace fluid losses
- Replace electrolyte
- Replace glycogen stores
-Protein (for resistance training)
When would you want a higher CHO concentration (~8%) and lower CHO concentration (6-8%) in sports drinks?
- Higher for energy provision (also long duration and cooler temperatures)
- Lower if hydration is the main factor (also during hot, humid, shorter duration)
