Exercise Physiology II Exam 1 Review
Blair et al., 1989
"Aerobics Center Longitudinal Study" This was the first study to demonstrate VO2 max at initial is the best predictor of all cause mortality in a group of thousands of people (10,000 men and 3,000 women)
Paffenbarger et al., 1986
"Harvard Alumni Study" established a strong link between physical activity level and all cause mortality. this was based on questionare data from Harvard alumni grads 17000 men over the course of x amount of years and they assessed physical activity throughout the weeks and mortality (17,000 men). Most physically active lived the longest.
Known heart murmur
Although some may be innocent, heart murmurs may indicate valvular or other cardiovascular disease. From an exercise safety standpoint, it is especially important to exclude hypertrophic cardiomyopathy and aortic stenosis as underlying causes because these are among the more common causes of exertion-related sudden cardiac death.
Unusual fatigue or shortness of breath with usual activities
Although there may be benign origins for these symptoms, they also may signal the onset of change in the status of cardiovascular disease or metabolic disease
Athroma
An area in an artery where the wall is damaged and accumulating calcified lipids
Analysis for CHD death vs sedentary lifestyle
Analysis for CHD death yielded a relative risk 1.9 times greater for sedentary versus active occupants
An individual has a weight in 198 pounds and their height is 70 inches. Calculate BMI.
Answer: 28.4 kg/m2
What is the U.S. life expectancy?
Around 80 years. The U.S. average life expectancy is among the lowest in industrialized nations
Physical activity and cancer
Available evidence for a protective effect of physical activity is strongest for overall cancer risk. colon and breast cancer specifically Colon: Sedentary lifestyle is linked to an increased risk of colon cancer in men and women. Individuals who ate processed meat are at risk for colon cancer. Breast: Epidemiologic evidence shows that physical activity reduces the risk of breast cancer following a dose-response pattern
Obesity (+)
BMI > 30 kg/m2, or Waist girth > 102 cm for men and 88 cm for women
What other measures are there?
BP Anthropometric and Body Composition Blood analyses
hypertension biological plausibility
BP = CO x TPR - blood pressure slightly declines because of cardiac drift - reduced Plasma volume - reduced post-exercise NE (reductions in norepinephrine and epinephrine) - increased insulin sensitivity - altered vascular responses (give vessels what they need in terms of getting them active)
What are some coronary risk factors?
Behavioral Genetic Biological Environmental
Ankle edema
Bilateral ankle edema that is most evident at night is a characteristic sign of heart failure or bilateral chronic venous insufficiency. Unilateral edema of a limb often results from venous thrombosis or lymphatic blockage in the limb. Generalized edema occurs in persons with the nephrotic syndrome, severe heart failure, or hepatic cirrhosis.
Physical activity and coronary heart disease (CHD)
CHD is the most studied chronic disease in relation to physical activity/fitness Physical activity is cardioprotective, and inactive is proatherogenic (atherosclerosis) A sedentary lifestyle is a predictor of disease - AHA guidelines for the primary prevention of CVD and stroke now emphasize regular physical activity
What do accelerometers do?
Can be worn on the trunk or limbs Measurements are proportional to muscular forces Most results from accelerometers are in proportion to energy expenditure Used to ascertain time, frequency, and duration of physical activity performed at various intensities Some measure only in vertical plane; others measure in three planes (vertical, horizontal, mediolateral)
List the pathophysological disorders
Cardiovascular, metabolic, or renal pain, discomfort in the chest Cardiovascular, metabolic, renal shortness of breath Dyspena Syncope Orthropena Ankle edema Palpitations Intermittent claudation Heart murmurs Shortness of breath
Cardiovascular, metabolic, or renal pain, discomfort in the chest
Character: constricting, squeezing, burning, "heaviness" or "heavy feeling" Location: substernal, across midthorax, anteriorly; in one or both arms, shoulders; in neck, cheecks, teeth; in forearms Provoking factors: exercise or exertion, excitement, other forms of stress, cold weather, occurance after meals
What is coronary artery disease involved in?
Coronary artery disease involves the localization of plaque in coronary arteries
Current Cigarette Smoking (+)
Current smoker or those who quit within previous 6 months
When does atherosclerosis become dangerous?
Damage to the vessel wall and that damage creates an area of tuberulant flow. Because of the turbulant flow, we accumulate lipids and becomes inflammed and attracts more immune mediators, more platelets, and we have this large group of gunk in the coronary artery. This large group of gunk will harden and become plaque and if that plaque obstructs blood flow, blood is not going to reach that area of the myocardium and a myocardial infarction will result.
Pre-screening: (Participates in Regular Exercise): Any signs or symptoms suggestive CV, metabolic, or renal disease
Discontinue exercise and seek medical clearance May return to exercise following medical clearance
What happens during exercise when syncope occurs?
Dizziness and, in particular, syncope during exercise may result from cardiac disorders that prevent the normal rise (or an actual fall) in cardiac output
Cardiovascular, metabolic, or renal shortness of breath
Dyspnea
Physical activity, Type 2 diabetes and metabolic syndrome
Epidemiologic studies (looking at numbers over years) - Nurses' Health Study - Physicians' Health Study - The Health Professions' Follow-up Study Recent large-scale intevention studies (tells more) - Finnish Diabetes Prevention Study (DPS) - U.S. Diabetes prevention Program (DPP) All these studies promote physical activity for the prevention and or progression of type 2 diabetes, obesity, metabolic syndrome
What are the positive coronary risk factors?
Family History Current Cigarette Smoking Hypertension Hypercholesterolemia Diabetes Obesity Sedentary
What is the best indictor for morbidity and mortality?
Family history
Diabetes (+)
Fasting blood glucose of ≥ 126 mg/dL, or 2h OGTT ≥ 200 mg/dL or HbA1 ≥ 6.5
What are the limitations of heart rate monitoring?
HR is increased by temperature, humidity and high altitude, and these may result in overestimation of energy expenditure Emotional state, hydration status, type of contraction (static vs. dynamic), and the amount of muscle mass recruited will affect HR, independent of physical activity level.
What is the leading cause of death?
Heart Disease
What is the one negative coronary risk factor?
High HDL-C
What are the modifiable risk factors?
Hypertension Hyperlipidemia Smoking Physical Inactivity Obesity (Metabolic Syndrome) Diabetes
What role does physical activity have in delaying the prevelance of hypertension?
Hypertension isideipathic. Individuals who are physical active and of a more healthy weight have less incidence of hypertension than individuals who are not physically active and are obese We need physical activity coupled with weight management for hypertension.
Ischemia
If the plaque blocks the vessel, we have restriction of blood flow
Aerobics Center Longitudial Study
Individuals who were the most fit were at quartile 5 and individuals who were the least fit were at quartile 1. The relative risk of mortality decreased in each mortality. For men, it decreased at quartile 5, and for women, at quartile 4. For individuals who are fitter, the relative risk of mortality declines.
Hypercholesterolemia (+)
LDL - C > 130 mg/dL: from liver to the body TC > 200 mg/dL, or HDL < 40 mg/dL: transfers back to the liver Or on lipid lowering medication Statant
What is Heart rate monitoring?
Lifestyle activity energy expenditure measured with indirect calorimetry is highly correlated (0.87) with energy expenditure measured with HR monitoring. Stronger correlation than lifestyle activity energy expenditure between indirect calorimetry and accelorometers for lifestyle activities Heart rate is an objective measure to assess physical activity.
Hyperlipidemia
Lower HDL-C associated with CHD regardless of TBC Reverse Cholesterol transport Leon and Sanchez 2001 (5%) Red wine can increase HDL levels by 5% HDL is going to transport cholesterol to the liver.
What is the life expectancy in males and females?
Males: over 75 Females: over 80 Females live longer than males
Pre-screening: (Does not Participate in Regular Exercise): No CV, metabolic, or renal disease
Medical Clearance Not necessary Light to Moderate Intensity Exercise Recommended
Pre-screening: (Does not Participate in Regular Exercise): Known CV, Metabolic, or renal disease and Asymptomatic
Medical Clearance Recommended Following Medical Clearance, Light to moderate Intensity Exercise Recommended May gradually progress
Pre-screening: (Participates in Regular Exercise): Known CV, Metabolic or Renal Disease
Medical Clearance for Moderate Intensity Exercise Not Necessary; Medical Clearance (within the last 12 months if no change in signs/symptoms) Recommended Before engaging in vigorous intensity exercise Continue with moderate intensity exercise
Pre-screening: (Participates in Regular Exercise): No CV, metabolic or renal disease
Medical Clearance not necessary Continue Moderate or Vigerous Intensity Exercise
Pre-screening: (Does not Participate in Regular Exercise): Any signs or symptoms of CV, metabolic, or renal disease
Medical Clearance recommended Following medical clearance, light to moderate intensity exercise recommended May gradually progress
Hypertension
Most of the time, there is no known cause of hypertension 20% of population has hypertension Physical activity and prevention/treatment
physical activity and stroke
Most studies show a trend toward an increased risk of stroke among those who are physically inactive - most studies are limited by less stringent designs One study examined an objective measure of cardiorespiratory fitness in relation to the risk of mortality from stroke - Men in the low-fitness category had 2.70 and 3.13 times the risk of stroke during the follow-up period compared with men in the moderate- and high-fitness categories, respectively.
Family History (+)
Myocardial infarction, coronary revascularization, or sudden death before 55 years in father or other male first-degree relative or before 65 years in the mother or another female first-degree relative
What is the difference between modifiable risk factors and non-modifiable risk factors?
Non-modifiable risk factors, we can do something about it Modifiable risk factors, we can impact
Cardiovascular, metabolic, or renal orthopnea
Orthopnea refers to dyspnea occurring at rest in the recumbent position that is relieved promptly by sitting upright or standing
Disadvantages of Subjective Measures
- Inaccurate recall - Fails to accurately capture all types of activity (e.g. moderate, lifestyle, and occupational activity) - Not recommended for children younger than the age of 10 yr
Palpitations or tachycardia
Palpitations (defined as an unpleasant awareness of the forceful or rapid beating of the heart) may be induced by various disorders or cardiac rhythm. These include: tachycardia, bradycardia of sudden onset, ectopic beats, compensatory pauses, and accentuated stroke volume resulting from valvular regurgitation. Palpitations also often result from any anxiety states and high cardiac output states, such as anemia, fever, etc.
Sedentary: (+)
Persons not participating in a moderate-intensity activity (40-59%VO2) on at least 3 days/week FITT principle Accumulation time: low to moderate: 30 minutes
A 22-year-old recent college graduate is joining a gym. Since becoming an accountant 6 mo ago, she no longer walks across campus or plays intramural soccer and has concerns about her now a sedentary lifestyle. Although her body mass index (BMI) is slightly above normal, she reports no significant medical history and no symptoms of any diseases, even when walking up three flights of stairs to her apartment. She would like to begin playing golf
Prescreening: Does not exercise regularly No known symptoms or medical history of any diseases No Medical Clearance Necessary May continue light to moderate intensity exercise
A 60-year-old woman is beginning a professionally led walking program. Two years ago, she had a drug-eluting stent placed in her left anterior descending coronary artery after a routine exercise stress test revealed significant ST-segment depression. She completed a brief cardiac rehabilitation program in the 2 months following the procedure but has been inactive since. She reports no signs or symptoms and takes a cholesterol-lowering statin and antiplatelet medications as directed by her cardiologist
Prescreening: Does not participate in exercise Known Cardiovascular Disease Medical Clearance is Recommended May continue light to moderate exercise
A 50-year-old nonsmoking male was recently invited by colleagues to participate in a 10-km trail run. He reports currently walking 40 min on Monday, Wednesday, and Friday — something he has done "for years." His goal is to run the entire race without stopping, and he is seeking training services. He reports having what he describes as a "mild heart attack" at 45 yr old, completed cardiac rehabilitation, and has had no problems since. He takes a statin, an angiotensin-converting enzyme (ACE) inhibitor, and aspirin daily. During the last visit with his cardiologist, which took place 2 yr ago, the cardiologist noted no changes in his medical condition
Prescreening: Exercise: Exercises Known Cardiovascular disease medical clearance recommended may follow light to moderate exercise
A 35-year-old business consultant is in town for 2 wk and seeking a temporary membership at a fitness club. She and her friends have been training for a long-distance charity bike ride for the past 16wk; she is unable to travel with her bike and she does not want to lose her fitness. She reports no current symptoms of CV or metabolic disease and has no medical history except hyperlipidemia, for which she takes an HMG-CoA reductase inhibitor (statin Daily) Case Studies PreScreening
Prescreening: exercise No symptoms of Cardiovascular disease No medical clearance is necessary May continue with moderate to vigorous intensity exercise
A 45-year-old former collegiate swimmer turned lifelong triathlete requests assistance with run training. His only significant medical history is a series of overuse injuries to his shoulders and Achilles tendon. In recent weeks, he notes his workouts are unusually difficult and reports feeling constriction in his chest with exertion — something heat tributes to deficiencies in core strength. Upon further questioning, he explains that the chest constriction is improved with rest and that he often feels dizzy during recovery
Prescreening: exercise Signs and Symptoms of cardiovascular disease Medical Clearance is Necessary so he must seek medical clearance May return to exercise following medical clearance
What must be considered in an informed consent document?
Program goals Procedures Risks associated with participation Potential benefits associated with participation
Advantages of Objective Measures
- Not subject to recall error - Small and lightweight - Unobtrusive
Physical activity and Type 2 diabetes
Prospective studies indicate a protective effect of physical activity for Type 2 diabetes A dose-response relationship exists in which greater levels of physical activity result in a lower risk for the development of Type 2 diabetes Interventional studies (DPS and DPP) indicate that leading a healthy lifestyle, including being physically active, is an effective prevention strategy for Type 2 diabetes Lifestyle intervention can be very effective. Type 1 diabetes is autoimmune. There can be autoimmune component to the type 2 diabetes. This is to predict whether the subject needs to take medicine someday. If you have impaired fasting glucose, those are warning signs. If you reach the criteria for diabetes, you are getting antibody testing.
Questionnaries
Range from single question to highly detailed Includes Type of activity, frequency, intensity, and time
Diaries
Range from single to highly detailed - Simple: 4-h time blocks accounting for only intensity - ACTIVITYGRAM - Detailed: minute-by-minute account of activity
Relative risk of CHD death vs high nonoccupational physical activity
Relative risk of CHD death was 1.9 times greater for low versus high nonoccupational physical activity
CHD and sedentary
Relative risk of CHD is 1.4 times greater for sedentary versus active occupations
CHD and nonoccupational physical activity
Relative risk of CHD is 1.6 times greater for low versus high nonoccupational physical activity
Sarah is 38 years old. She is 120 lbs and 65" tall with a waist-to-hip ratio of 74. She is a non-smoker who reports being physically active. You took her BP and it was 142/90. Her TC is 220, LDL is 135, and HDL is 50. Her fasting blood glucose is 90. Her father died at age 58 of a MI.
Risk Factors: High TC, High LDL so she has hypercholesterolemia. Nonrisk factors: No hypertension, no high HDL, no diabetes, no obesity because her BMI is less than 30, no family history because her father did not die before the age of 55 of a MI, no waist-to-hip ratio.
Vern is a 32-year-old male. He is 245 lbs and 65" tall. His TC is 190, LDL is 99, and HDL is 45. His fasting blood glucose is 88. His blood pressure is 120/80. He is sedentary and reports severe leg pain with mild exertion. He tells you he wants to lose 50 lbs to impress a co-worker. His mother died at age 62 of a MI.
Risk Factors: Obesity due to a BMI over 30, family history because his maternal side (mother) died before the age of 66 of an MI, sedentary because he does not moderately exercise (3 days per week) Non-risk factors: No hyperlipidemia, normal blood pressure,
Fred is a 46 year old male. He weighs 180lbs and is 70" tall with a waist circumference of 90cm. He reports that the quick smoking 2 months ago and exercises 4x/week on a recumbent cycle in his garage. His LDL is 102, TC is 190, and HDL is 66. His fasting blood glucose is 98. He is currently taking Nifedipine (calcium channel blocker) for hypertension. He has no family history of MI.
Risk Factors: Smoking, negative for HDL, hypertension Nonrisk factors: BMI (25.6 kg/m2); LDL is less than 130 mg/dL; TC is less than 200 mg/dL. Fasting blood glucose is less than 126 mg/dL
Disadvantages of Objective Measures
- Specific types of activity assessed (e.g., water sports, arm exercise, inclined walking) - Extraneous variables may affect results - Usually more expensive than questionnaires
Obesity
Risk of hypertension, hyperlipidemia, diabetes Independent risk of CHD 55% Prevalence Overweight 20% Prevalence of Obese When the disease is present, exercise comes in after changing diet. Independent risk factors of obesity. BMI - Waist Circumference - WHR -
Hypertension (+)
SBP ≥ 140 or DBP ≥ 90, confirmed by measurements on at least 2 occasions, or an antihypertensive medication
What are the weaknesses of pedometers?
Sensitivity declines if titled away from the vertical plane - for obese, may fail to record steps at slow walking speeds if the belt is tilted The ankle device (Step Watch 3) is sensitive enough to detect frail, slow, shuffling steps
What are the accelerometer limitations?
Single-lane models may not accurately detect movement from activities such as bicycling, weightlifting, or swimming Unable to detect increased activity level resulting from upper body movement, carrying a load, or surface changes (e.g., hills)
What are the criteria of coronary risk factors?
Strength of association: (e.g. individuals with highest cholesterol have the highest risk for developing heart disease) Consistency: (you do this on several different occasions in different studies, has it been observed overtime) Temporal relationship: (time) Gradient: (a change; slope) Biological plausibility: (its possible and makes sense) Evidence: (is there peer reviewed studies that demonstrate the coronary risk factors)
Cardiovascular, metabolic, or renal dizziness or syncope
Syncope Dizziness
When is plaque clinically significant?
We don't consider it clinically significant until the plaque occupies over 75% of the cross sectional area of the lumen.
What can improve when wearing an accelerometer and an HR monitor?
Wearing an accelerometer and an HR monitor simultaneously may improve energy expenditure, estimation and classification of time spent in light, moderate, and hard activity.
How many cardiovascular deaths are in worldwide versus the developed nations?
Worldwide: 20% United States: 50%
Harvard alumni study
calculated kilocalories per week based on questionnaire. Relative to inactive risk was 1. When an individual doubled or over 500 calories per week, risks substantially dropped and risk dropped when you went higher in the physical activity index (kcal/week) Individuals with the highest reported physical activity did not seem to benefit as much (>3500). Overall active lifestyle, occupation driven, we have u-shaped thinking
Syncope
defined as a loss of consciousness is most commonly caused by a reduced perfusion of the brain
Dyspnea
defined as an abnormally uncomfortable awareness of breathing. It occurs during strenuous exercise in healthy, well-trained individuals
Pedometers
detect vertical accelerations of the body and record a "step" when vertical acceleration exceeds a threshold value (they count steps)
BMI, Waist Circumference, WHR
do not measure percent body fat - if you hit positive in BMI, Waist Circumference, you are obese
What is coronary atherosclerosis?
localized accumulation of lipid and fibrous tissue within the coronary artery
What is the relationship between socioeconomic status, race, and age and life expectancy, heart disease and diabetes?
lower socioeconomic status is associated with lower life expectancy. Individuals from minority groups have a higher incidence of heart disease and diabetes
Accelerometers
measure movement based on acceleration and deceleration of the body
intermittent claudication
refers to the pain that occurs in the lower extremities with an inadequate blood supply (usually due to atherosclerosis) brought on by exercise. The pain does not occur with standing or sitting, is reproducible from day to day, is more severe when walking upstairs or up a hill, and is often described as a cramp, which disappears within 1-2 min after stopping exercise. Coronary artery disease is more prevalent in individuals with intermittent claudication. Patients with diabetes are at increased risk for this condition
Why do we pre-screen indivduals?
to identify people who may have medical conditions which put them at a higher risk of an adverse event# during physical activity/exercise
Advantages of Subjective Measures
- relatively inexpensive - easy to administer - data collected for many individuals - can be ascertained with a few questions
How to calculate BMI?
1) Make sure the weight is in kilograms (to covert pounds to kilograms, you divide by 2.205) 2) Make sure the height is in meters (to convert inches to meters, you multiply by 0.0254). (to convert cm to meters, you multiply by 0.01) 3) You multiply the meters twice. You divide the weight in kilograms by meters squared. 4) SI units: BMI = kg/m2
What are the main causes of death in the U.S.?
1. Heart disease 2. Cancer 3. Respiratory Disease (pneumonia) 4. Stroke 5. Accidents 6. Alzheimer 7. Diabetes
High HDL-C: (-)
>60 mg/dL
What is plaque?
A build-up of cholesterol along the walls of arteries (fatty material): becomes more inflamed
What are the strengths of pedometers?
Accurate for recording the number of steps taken and distance walked Increase reliability for fasting walking and running places Accuracy not different by type of walking or running surface Relationship between step counts and energy expended in moderate-intensity activities was stronger than in vigourous activities Step count is more accurate than kilometers.
What are the non-modifiable risk factors?
Advancing Age Male Sex Family History
