Test 1 Flashcards
Risk factor of CVD INDEPENDENT of physical activity
Sedentary Lifestyle
Sedentary Lifestyle =
Less than 1.5 METS while in a sitting or reclining position during waking hours
Women over 30 with sedentary lifestyle
are at higher risk for CVD than smokers
Has shown to decrease plasma glucose and insulin
Regular activity (18, 1-minute 40 second walks is better than 15 minutes of continuous walking)
All Americans should participate in ___ min/wk of moderate intensity aerobic activity; ___ min/wk of vigorous intensity aerobic activity; or combination of both for substantial health benefits.
150, 75 (additional health benefits with 300 min/wk or more of moderate intensity aerobic activity; 150 min/wk or more of vigorous intensity aerobic activity; or combination of both)
Activity Recommendation for moderate/high intensity strenthening
2x per week
List Benefits of Regular Exercise
Premature mortality
CVD/CAD
HTN
Stroke
Osteoporosis/Osteopenia/Hip Fx
Type II DM
Metabolic syndrome
Obesity
Colon cancer & breast cancer
Depression
Functional Health/Falls
Cognitive Function
Increased VO2 max from both central & peripheral adaptations.
Decreased minute ventilation at given submax workload.
Decreased O2 cost for given submax workload.
Decreased HR & BP at given submax workload.
Increased capillary density in skeletal muscle.
Increased exercise threshold for accumulation of lactate; onset of disease signs/symptoms (angina, ST seg depression, claudication).
Aerobic Capacity is inversely related to
CVD
Physical Activity has shown to have a protective association against
breast, colon, lung, prostate cancer
Healthy People 2020
- Attain high quality, longer lives free of preventable disease, disability, injury & premature death. Ex—life expectancy, healthy life expectancy, physical & mental unhealthy days, chronic disease prevalence, activity limitations.
- Achieve health equity, eliminate disparities, and improve health of all ages. Ex—race/ethnicity/gender, SES, disability status, geography, sexual orientation.
- Create social & physical environments that promote good health for all. Ex—social & economic factors, natural & built environments, policies & programs.
- Promote QOL, healthy development, and healthy behaviors across all life stages. Ex—well being/satisfaction, physical, mental & social QOL, participation in common activities.
Overweight
body weight that exceeds some average for stature, and perhaps age, usually by some standard deviation unit or percentage.
BMI
Overfatness
body fat that exceeds an age- and/or gender-appropriate average by a set amount. (energy intake chronically exceeds energy expenditure)
Obesity
overfat condition that accompanies a constellation of comorbidities
Genetics
increased susceptibility of becoming obese
Leptin
Congenital absence of leptin hormone, the body− weight-regulating substance produced by fat and released into bloodstream acting on hypothalamus.
Neither short- nor long-term exercise meaningfully affects leptin levels.
Current national guidelines for physical activity
30-60 min/day
Excess Body Fat vs. Excess Body Weight
“In all likelihood, excess body fat, not excess body weight per se explains the relationship between increased body weight & disease risk”
Body Fat norms for young men/women that indicate excessive body fat
men: above 20%
women: above 30%
Central or android-type obesity (apple)
Abdominal area fat (visceral adipose tissue [VAT]) relates to altered metabolic profile– increased CHD risk, metabolic syndrome
Peripheral or gynoid-type obesity (pear)
reduced metabolic health risk
more difficult to reduce this fat
Waist to Hip Ratio
waist girth/hip girth
Normal BMI
18.5 - 24.9 kg*m-2
Overweight BMI
25 - 29.9 kg*m-2
Obese class I BMI
30 - 34.9 kg*m-2
Large Waist girth (men: 102cm, women: 88cm) and obese =
very high health risk
Fat Cell Hypertrophy
existing adipocytes enlarge or fill with fat
Fat cell hyperplasia
total adipocyte number increases
Total adipocyte number
body mass fat/ Fat content per cell
Overweight/Obese person should reduce initial body weight by no more than
5-15% (any more could be an unattainable target)
To lose weight, reduce caloric intake by no more than
500-1000 kcals.
moderate vs severe reduction in food intake
moderate produces greater fat loss
Potential for long term success in weight loss is ______ related with the initial degree of obesity
inversely
A well-regulated internal control mechanism located deep within lateral hypothalamus that maintains a preset level of body weight and/or %fat
Setpoint
Dieting effect on setpoint
little to none
Weight loss relationship with metabolic rate
metabolic rate decreases as weight loss increases (as a result of dieting) –> produces weight loss plateau
The ____one is at the start of weight loss, the more vigorously the body attempts to ____ weight
fatter, regain
Early weight loss is mostly___? what percent?
water, 70% over the first few weeks.
Negative Energy/Caloric Balance =
weight loss
With low-to-moderate physical activity, recovery calories to total energy expenditure remains small relative to physical activity caloric expenditure.
Range?
up to 75 kcal for exercise durations of 80 min.
Regular physical activity with dieting..
greater fat loss, less lean tissue loss, enhancement of physical capacity
Effect of dieting (only) on muscle mass
may result in decreased muscle mass without exercise
Resistance Training effect on metabolic rate
increases metabolic rate
for weight loss, focus on increasing exercise ______(duration or intensity)
duration
Energy cost of weight bearing exercise relates directly to ____
body weight (heavier person expends more energy than average weighted person)
meaningful changes in body weight and body composition require at least _____ weeks
12
Ideal weight loss combo
caloric restraint + exercise
Spot reduction
does not work
(Men/Women) respond more favorably to effects of physical activity on weight loss
Men
(Men/Women) distribute more fat in upper body and abdominal region
Men
Limitations of Height-Weight Tables
- Uses unvalidated estimates of body frame size.
- Developed from data derived primarily from white populations.
- Specific focus on mortality data that may not reflect obesity-related comorbidities.
- Provide no assessment of body composition.
BMI (Body Mass Index)
Body Mass (kg) / stature (m^2)
BMI vs Health Risks
Increased BMI results in more severe health risks
BMI Limitations
- Current overweight classification assumes the relationship between BMI and %fat (and disease risk) remains independent of age, gender, ethnicity, and race.
- Fails to consider body’s proportional composition or fat distribution.
- Factors other than excess fat (bone, muscle, and increased plasma volume induced by training) affect body weight.
- Possibility of misclassifying someone as overweight pertains particularly to athletes.
Fat in heart, lungs, liver, spleen, kidneys, intestines, muscles, and lipid-rich tissues of central nervous system and bone marrow.
Required for normal physiologic functioning.
Essential Fat
Energy reserve primarily in adipose tissue.
83% pure fat, 2% protein, and 15% water
Visceral fat protects various internal organs
Storage Fat
Hydrostatic weighing—underwater weighing Anthropometric measurement (girths, skinfolds). Other methods (x-ray, MRI, BIA, near-infrared interactance, ultrasound, CT, air plethysmography)
Indirect Body Composition Measurments
Hydrostatic Weighing: Archimedes’ Principle
Water displacement and hydrostatic weighing
Body volume = loss of weight in water (need temperature correction for water’s density)
hydrostatic weighing
Siri Equation for Percent Body Fat (densities of lean tissue and bone components remain constant
= (495/body density) - 450
BOD POD measurements of Body Volume
determines body volume by measuring initial volume of empty chamber minus volume with person inside
Common Skinfold Locations
Triceps, subscapular, iliac, abdomen, thigh
Landmarks for Girth Measurments (useful for analyzing body fat distribution and weight loss patterns)
forearm, bicep, belly button, hips, thigh, calf
DXA (dual-energy x-ray absorptiometry)
quantifies fat and nonbone regional lean mass plus mineral content of deeper bony structures (valid and shows comparable results to hydrostatic weighing)
Carbohydrates
become available as energy source, form glycogen stores in liver and muscle, convert to fat for later energy use
Carbohydrate’s role in the body
Energy source during intense exercise Energy derived from breakdown of blood-borne glucose and muscle glycogen. Protein sparer Helps preserve tissue protein Metabolic primer Serves as “primer” for fat oxidation Fuel for the central nervous system Serves as primary fuel for nerve tissue
Primary fuel during high intensity short duration exercise
Carb
Primary fuel during low intensity exercises
Fat
Fuel after glycogen stores are depleted
Fat
HDL
good, protects against heart disease
LDL
bad
Role of Lipids
energy source, easily stored, thermal insulation, hunger suppressor
Protein sythesis
large increases during recovery from endurance and resistance exercise
Recommended Carb intake
Sedentary 70kg person
300g or 40-50% of total daily calories
Physically active person
400-600g or 60% of total daily calories
Endurance Athlete
70% of total daily calories (8-10g per kg body mass)
Biological Functions of Vitamins
Vitamins contain no useful energy; instead, they serve as essential links and regulators in metabolic reactions
Vitamins also control tissue synthesis and protect the integrity of the cells’ plasma membrane
Vitamins and Exercise
Vitamin supplements are no less effective for bodily functions than vitamins from food, although vitamins in food form provide an additional array of important nutrients.
When vitamin intake achieves recommended levels, supplements do not improve exercise performance.
Supplements do not improve exercise performance, hormonal and metabolic responses to exercise, and ability to train arduously and recover from such training in adequately nourished individuals.
body’s most abundant mineral
calcium
weakened bone, increased fracture risk
osteopenia
bone loses its calcium mass and concentration, which causes bone to progessively become more porous and brittle
osteoporosis
Female Athlete Triad
disordered eating, osteoporosis, amenorrhea
At risk for Iron deficiency
women of child bearing age and those on vegetarian diets
Exercise Induced Anemia
Strenuous training may create added demand for iron that exceeds its intake, resulting in an “iron drain” and reduced physical performance.
electrolytes
sodium, potassium, chlorine. promote exchange of of nutrients and waste products
40-70% of body mass
water
Muscle = ___% water
70%
Fat = ___% water
10%
3 factors that determine amount of water loss during exercise
- physical activity intensity
- temperature
- humidity
Carbohydrate Atwater value
4 kcal/g
Lipid Atwater Value
9 kcal/g
Protein Atwater Value
4 kcal/g
Alcohol Atwater Value
7 kcal/g
Involves all chemical reactions of biomolecules within the body that encompass synthesis/anabolism and breakdown/catabolism
Metabolism
3 Factors affect total daily energy expenditure (TDEE)
- Resting Metabolic Rate (60-75%)
- Thermogenic effect of food
- Energy expended during physical activity and recovery
Minimum level of energy to sustain vital functions in the waking state. Reflects the body’s total heat production.
Basal Metabolic Rate
Influenced by body size, health/fitness, muscle mass, age, hormones, body temperature. Always slightly higher than BMR.
Resting Metabolic Rate
Regular physical activity offsets _____ in BMR and RMR that occur with aging
decreases
Each 1 lb. gain in FFM increases RMR by
7-10 kcal per day
Food consumption increases/decreases energy metabolism
increases
Classifies work as the ratio of energy required for a task to the resting energy requirement
Physical Activity Ratio
Light work-3x
heavy work-6/8x
max work- 9x and above
MET
Metabolic Equivalent
ex. 2 METs requires 2x Resting Metabolism
Heart Rate and VO2 are directly related
true
Gross Energy Expenditure
includes Resting Energy Expenditure
Net Energy Expenditure
is the true energy expenditure of an activity. GEE - REE
Relates to the amount of energy required to perform a task, to actual energy requirement of work done
Mechanical Efficiency (walking/running = 25%)
More economical to stop walking and begin running at speeds ____
greater than 8km/h (5mph)
*independent of fitness
Running a mile at 10mph requires _____ as much energy as 5mph
twice
Energy requirement of each mile run is ______
constant (regardless of fitness level)
At a particular speed, elite endurance runners run at a (higher/lower) oxygen uptake than a less trained person of the same age and gender
lower
Children/adolescents have a higher oxygen consumption than adults in weight bearing activities due to
- larger ratio of surface area to body mass
- greater stride frequencies
- shorter stride lengths
- differences in mechanics that reduce movement
Swimming vs running energy expenditure
Swimming requires more energy to maintain buoyancy while simultaneously generating horizontal arm and leg movements. Additional drag forces are also important
BP in response to resistance exercise
increases fairly linearly as exertion increases
SBP declines as _____ continues because arterioles in active muscles continue to dilate
steady state exercise
SBP increases linearly with exercise intensity (T/F)
True
DBP remains stable or decreases slightly with higher exercise levels (T/F)
True
exercise with arms produces (higher/lower) SBP and DBP
higher
Cardiac Output
HR x SV
Cardiac Output at Rest
males: 5 L/min
females: 4 L/min
Enhancing Diastolic Filling will (increase/decrease) SV
increase
HR can increase as a result of anticipation of exercise (T/F)
True
CO max and VO2 max are directly related (T/F)
True
Upper body has (higher/lower) mechanical efficiency
lower
