Obtain the Laplace transform of f(t) in Fig. 15.28.
Fitness characteristics that enable the body to perform physical activity Physical inactivity (being sedentary) linked with many diseases heart disease, cancer, stroke, diabetes, hypertension Both PA and exercise involve body movement, muscle contraction and enhanced energy expenditure but exercise describes structured PS and usually repetition of certain movements. Aerobic PA activity in which the body's large muscles move in a rhythmic manner for a sustained period of time; requires oxygen. aerobic activity or endurance activity improves cardiorespiratory fitness Guidelines for PA brisk walking, running, swimming, bicycling Minimum amount of time performing aerobic physical activity extensive health benefits BMI 18.5 24.9 is used as a goal Level of intensity: light little to no increase in heart rate. <5 for perceived exertion. able to sing for talk test <3.5 kcal/mn for energy expenditure walking pace is < 3mph Moderate heart rate some increased perceived exertion 5 or 6 talk test able to have a conversation energy expenditure 3.5 to 7 kcal/min walking pace 3 to 4.5 mph Vigorous heart rate large increase perceived exertion 7 to 8 talk test conversation is difficult or "broken" energy expenditure > 7 kcal/min walking pace > 4.5 mph The American college of sports medicine guidelines for physical fitness recommends at least ___ minutes of cardiorespiratory activity per day 30 Hypertrophy gaining muscle tissue; protein synthesis is greater than degradation atrophy when protein degradation is greater than synthesis developing fitness muscles respond to overload conditions (extra physical demand on the body) components of fitness flexibility, muscle strength and endurance, cardiorespiratory endurance. strategies to build fitness and prevent injuries be active all week use proper equipment and attire use proper form include warm up and cool down challenge your strength and endurance a few time a week pay attention to body signals include at least one day of rest Cardiorespiratory endurance length of time a person can remain active with an elevated heart rate. enhances capacity of heart, lungs and blood. mind and body benefit Cardiorespiratory conditioning aerobic workouts improve hear and long activities. enhanced oxygen delivery slower heart rate more efficient breathing improved circulation lower blood pressure Cardiorespiratory conditioning defined activity sustained for 20 minutes or more. use most of large muscle groups. intensity must elevate heart rate still able to talk comfortably workouts are safe up to 85% of a person's maximum heart rate muscle conditioning muscle conditioning fit muscles use oxygen efficiently. reduces the heart's workload and burns fat longer. Balanced fitness program levels of intensity varies activities you enjoy doing addresses all aspects of fitness a sample balanced fitness program includes a warm up and a cool down for 5 to 10 minutes Resistance training use of free weights or weight machines to provide resistance for developing muscles strength, power, endurance (weight training) What is the purpose for resistance training build muscles mass, develop and maintain muscle strength, power and endurance What are the benefits for resistance training prevention of chronic diseases. Maximize and maintain bone mass. improve posture and reduce risk of back injury. energy systems and fuels to support PA ATP small amounts in all body tissues all the time. delivers energy instantly chemical force for muscle contraction: mechanical movement, generates heat, 3 major energy systems enable muscles cells to regenerate ATP during PA what are the three energy systems 1. The phosphagen system. 2. The lactic acid system 3. The aerobic system The phosphagen system. what does it create Creatine phosphate (CP) Where is CP stored in the muscles How is CP split anaerobically. releases phosphate which replenishes ATP supplies. When is it produced during rest. used during activity The lactic acid system. When does it kick in about 10 seconds of intense PA. How does it split anaerobic muscle glycogen primary source of glucose Anabolic breakdown of glucose to pyruvate. Then pyruvate to lactate This system can generate a small amount of ATP quickly. Supports up to 3 minutes of intense activity. The aerobic system is used to meet the prolonged demands of sustained PA. Carbohydrate, fat, and amino acids are continuously oxidized to provide ATP. What happens during rest body derives most of its ATP from oxidation of fatty acids and glucose During PA, body adjust fuel mixtures muscles always use a combination of fuels. The effects of diet on physical endurance. Fat and protein diet 57 min normal mixed diet 114 min high carbohydrate diet 167 min Glycogen stores in the body. Body's glycogen supplies limited to about 2000 kcal. enough for about 20 miles of running. When glycogen depleted, muscles fatigue. What influences how much glycogen is stored. the amount of carbohydrate in the diet. The more CHO intake results in more glycogen storage. High intensity activities use more glycogen. What is the product of anaerobic glycolysis Lactate When does lactate accumulate during high intensity activities. When accumulation rate exceeds rate of clearing from the blood, intense activity can only be sustained 13 minutes lactate quickly leaves the muscles. travels in the blood to the liver. liver enzymes convert back into glucose recycling process of lactate to glucose cori cycle fuel duration of activity affects glycogen use what does the body use for fuel glycogen As aerobic activity sustained, body uses more fat and less glucose Glucose depletion is known as gluconeogenesis: can not support intense activity indefinitely. 2 to 3 hours of strenuous activity depletes stores. continued exertion becomes almost impossible. What are some strategies to combat glucose depletion eat a high CHO diet regularly consume glucose periodically during prolonged exercise (sports drinks) eat CHO rich foods immediately following PA CHO loading train muscles to store as much glycogen as they can. how many grams of CHO per kg body weight 8 grams fat intake recommendations for athletes same as general population. 20 to 35% of energy from fat. Less than 10% from saturated fat body fat stores can fuel hours of activity without running out factors affecting fat use longer duration and intensity of activity training permits body to draw more heavily on fat as fuel. Protein use during PA and between times of PA not a major fuel for PA. used to build muscle and other lean tissue. Protein synthesis differences during PA and rest. synthesis of body proteins suppressed during PA. When does it accelerate in hors following PA, eating high CHO foods after exercise accelerate muscle glycogen storage. Athletes use more what as fuel protein. muscles speeds up use of amino acids. 10% of total fuel during activity and rest. athlete's diet adequate energy and CHO intensity and duration protein needs are higher for athletes but meet CHO needs first so protein can be used for protein functions. What are the roles for vitamins and minerals to support PA assist in releasing energy from fuels. transport oxygen. supplements do not enhance performance of well nourished people deficiencies of nutrients impede performance. Vitamin E is also known as the antioxidant Which age group is iron deficiency most prevalent in active young women, vegetarian athletes iron deficiency anemia impairs performance sports anemia adaptive, temporary response. recommendation for athletes are individualized. Fluids and electrolytes to support activity water loss sweating and breathing. dehydration. temperature regulation In hot humid weather, sweat does not evaporate well. hyperthermia (high body temp) heat stroke prevention hypothermia (low body temp) symptoms: clumsiness, confusion, drowsiness, shivering (early symptom), cessation of shivering (late symptom) Both heat stroke and hypothermia can have some similar symptoms clumsiness, confusion, loss of consciousness Hydration hydrate before activity drink extra fluid in the days before event. rehydrate during and after fluids for endurance athletes CHO cottoning beverages When are electrolyte losses and replaced losses occur with sweating and replacement in regular foods or sports drinks. Hyponatremia decreased concentration of blood sodium; serious condition (seizure, vomiting, headache, bloating, puffiness) Loss of sodium when sweating profusely and excessive plain water consumption can lead to hyponatremia What is the best choice for most people water. sports drink offer: fluid, glucose, sodium and other electrolytes, good taste. sports drinks with a CHO content of ____ CHO are best for athletes participating in PA lasting 1 hour or longer 6 to 8 % 22 g of CHO per sv / 360 mL (12 oz) X 100 = 6% CHO Other fluids. Enhanced water (flavored, added sugars, vitamins, minerals, sometimes protein) neither natural nor healthy, plain water or juice can meet fluid needs. Athletes need sports drinks. Caffeine excesses can hinder performance potentially dangerous (energy drinks) Alcohol negative effects, does not provide energy to muscle. diets for physically active people: water thirst is a late signal of need. nutrient density foods with vitamins, minerals and energy carbohydrates pre game meal: 300800 kcal, easily digested foods, CHO rich healthy food, plenty of fluids, not high fiber foods, 34 hours before competition No single food improves skill, speed or strength some kinds of foods support better performance post game meal CHO rich food or beverages Ergogenic acids substances or treatments: purportedly increase athletic performance beyond what is possible through training What are the categories of ergogenic acids 1. those that perform as claimed 2. those that may perform as claimed insufficient scientific evidence 3. those that do not perform as claimed 4. those that are dangerous, illegal or banned. creatine enhance performance during intense PA sodium bicarbonate maintains muscle PH levels creatine supplementation causes weight gain creatinine is produced from creatine what is creatinine a chemical waste molecule generated from muscle metabolism What percent of the body's creatine is converted to creatinine everyday and transported through the bloodstream to the kidneys 2% what filters out most of the creatinine and excrete it in the urine. kidneys HMB metabolite of amino acid leucine, increased muscle mass and strength in untrained individuals, questions remain in trained athletes. Ribose helps resynthesize muscle ATP research has not shown improvement in athletic performance That do not perform as claimed Carnitine facilitates transfer of fatty acids across mitochondrial membrane. manufactures suggest greater fat oxidation. Chromium picolinate manufacturers suggest it helps build muscle, enhances energy and burns fat. research is lacking. Cr rich foods: whole grains, liver nuts. Dangerous, banned or illegal supplements. Anabolic steroids derived from male sex hormone testosterone. lean body mass. risks associated with use (rage, hostility, aggression, heart disease, liver damage) Herbal "steroid alternatives" none will enhance muscle strength. natural does not mean harmless. zygote fertilized ovum. rapidly divides to become blastocyst. implantation Embryo 28 weeks. has as complete nervous system by 8 weeks. Fetus 8 weeks to term. organs grow to maturity full term is 39 to 40 weeks. critical periods times of intense development and rapid cell division. when is the critical period for neural tube development between 17 to 30 days of gestation. Neural tube defects. Anencephaly brain is either missing or fails to develop spina bifida incomplete closure of spinal cord and bony encasement Chronic disease adverse influences at critical times during fetal development What is the most reliable indicator of infant health birth weight Weight prior to conception underweight high rates of preterm births and infant deaths. Over weight more medical complications. Macrosomia birth weight more than 9 pounds risks for infant poor health How much weight is gained in the first trimester 3.5 pounds. Then one pound per week thereafter carbohydrate ample carbohydrate is necessary to fuel fetal brain protein RDA: 25 grams per day higher supplements discouraged. essential fatty acids omega 3 and omega 6 fatty acids for brain material. Need for synthesis of DNA and new cells folate vitamin B12 iron zinc What are the nutrients for bone development vitamin D calcium other nutrients What is the ideal childbearing age 20 to 25 years old what age are women at higher risk for having children > 35 yrs old How much seafood should a pregnant women have limit to 12 oz per week or 6 oz cooked or canned white tuna Lactation is a normal physiological process. Hormones promote growth and branching of duct system and milk producing cells. prolactin is responsible for mild production oxytocin causes mammary glands to eject milk into duct. (let down reflex) Maternal energy and nutrient needs during lactation. energy intake and exercise. How many extra Kcalories per day 500 total water intake 3.8 liters per day Fetal alcohol syndrome (FAS) cluster of physical, mental and neurobehavioral symptoms. Cant be prevented or treated. drinking during pregnancy alcohol interferes with tissue development during critical periods. infant newborn to one year toddler one year to three years old preschool children 3 to 5 middle school 5 to 10 pre adolescence 9 to 11 for girls 10 to 12 for boys adolescence 11 to 20 Carbohydrate fuels what all cells. Brain size of infant proportionately larger than adult, 60% energy for brain is CHO FAt provides most of the energy in great milk and formula protein essential for growth. basic building material of body's tissues. "failure to thrive" seen in protein deficiency How long is break feeding is the best for one year Breast milk 39% CHO 55% fat 6% protein recommended adult diets 53% CHO 26% fat 21% protein infant formule 42% CHO 49% fat 9% protein Cow's milk not advised before age one. a poor source of iron and vitamin C. When to being introducing solid foods between 4 to 6 months choice of infant foods. What foods should you omit honey and corn syrup what is the fiber recommendation for 1 to 3 yrs old 19g per day fat and fatty acids recommendations 30 to 40% for 1 to 3 yrs old 25 to 35% for 4 to 18 yrs old considerations for protein intake nitrogen balance quality of protein added needs for growth considerations for vitamins and minerals needs increase with age iron and vitamin D supplements Malnourished children are vulnerable to what lead toxicity low intakes of calcium, zinc, vitamins C and D and iron What % of young children have hyperactivity 5% Prevalence of true food allergies in children: 48% in children younger than 4 yrs Food allergy anaphylactic shock. what is the most common causes in children: peanuts, eggs, soy and milk Food intolerance milk lactose is most common. reactions to chemicals in foods. symptoms without antibody protection Childhood obesity overweight above 85th percentile obesity above 95th percentile severe obesity above 99th percentile nutrition during adolescence energy and nutrient needs are highest in adolescence (expect pregnancy and lactation) large number of US children diagnosed with obesity and serious adult diseases type 2 diabetes and hypertension role of genetics a permissive role rather than a determining role risks factors for type 2 diabetes obese (most important) sedentary family history of diabetes obesity. LDL ____ HDL ____ LDL increases HDL decreases Blood pressure. Hypertension accelerates development of atherosclerosis