Nutrition & Fitness Lecture 17 March 26, 2015 Dr. Quadro Mens sana in corpore sano Roman poet Juvenal

Nutrition & Fitness

Lecture 17March 26, 2015

Dr. Quadro

Mens sana in corpore sanoRoman poet Juvenal

Department of Food Science

Lecture 17: March 26, 2015

Overview

WARM UPKnow what fitness and nutrition are

WORKOUTUnderstand the components of fitness

COOL DOWNSummary



WARM UP



What is Nutrition?

What is Fitness?

What are the benefits of Physical Activity?



A function of living plants and animals, consisting of the ingestion and metabolism of food material whereby tissue is built up and energy liberated – NUTRIENTS!!!!

The study of the food and liquid requirements of human beings or animals for normal physiological function, including energy need, maintenance of growth, activity, reproduction and lactation.

Nutrition



Physical fitness is the body’s ability to meet physical demands and is composed of

EnduranceStrengthFlexibility

Fitness is gained over timeDetermined by a combination of regular activity and genetically inherited ability.Not restricted to an athlete

Fitness – essential for good health



Nutrition and Fitness linked???

Optimal Nutrition Athletic Performance

Regular Exercise Ability to Use and Store Nutrients Optimally



Yesterday’s Genes, Today’s Lifestyle

12 easy ways to be sedentary:

Cellular phonesComputer gamesDishwashersDrive-through windowsE-mail/InternetEscalators & elevatorsFood delivery servicesGarage door openersHousekeeping and lawn servicesMoving sidewalksRemote controlsShopping by phone/computer



Preagricultural hunter-gatherers

Burned ~3000 calories/dayModerate physical activity >30 min/dayFeast or famineLean wild game or fishUncultivated fruits & vegetables

Industrialized modern humans

Burn ~1800 calories/daySedentaryAbundance of foodGrain-fattened meatsRefined sugar



To exercise or not to exercise?

Regular and moderate exercise that gets the heart beating and forces the muscles to work harder

Not needed to be strenuous

Seven out of 10 American adults don't exercise regularly – 25% don’t do exercise at all!!!

The Institute of Medicine recommends that we spend a total of at least 60 minutes on most days of the week engaged in physical activity.

Not need to be continuous

Exercise





The Benefits of Physical Activity

Increased self-confidenceEasier weight controlMore energyLess stress and anxietyImproved sleepEnhanced immunityLowered risk of heart disease

Lowered risk of certain cancersStronger bonesLowered risk of diabetesLowered risk of high blood pressureIncreased quality of lifeIncreased independence in life’s later years



Physical activity and cancer prevention : pathways and targets for intervention.Sport Medicine 2008



WORK OUT



What are the components of Physical Activity?

What is required for Physical Activity?

What fuels are needed for Physical Activity – Carbohydrate, fat or protein?

Is Fluid Balance important?

Are Vitamins and Minerals Required?



The Components of Fitness

WHAT IS FITNESS??WHAT IS FITNESS??Ability to perform routine physical exercise without fatigue

Improved with exercise

Different for everyone – level defined byFlexibilityStrengthEnduranceBody Composition




PHYSICAL CONDITIONINGPHYSICAL CONDITIONINGA planned program of exercise directed toward improving the function of a particular body system.

Placing regular, physical demand on the body and forcing the body to do more will cause it to adapt and function more efficiently = OVERLOAD.

A principle of training is that for a body system to improve, its workload must be increased by increments over time.The more you do it – the better you get




105-172 bpm

Physical ConditioningPhysical ConditioningApplying overload to increase strength and size:

Increase Frequency (more often) ~3-5 sessions/wkIncrease Intensity (more strenuous) ~55-90% MHRIncrease Time (exercise longer) ~>20-30min/session




STRENGTHSTRENGTHthe ability of muscles to work against resistance.Increased by repeatedly using the muscle against resistance – strength/weight training

Purpose of strength training: Build well-toned muscles to help accomplish activity - muscle fibers increase and thicken - HYPERTROPHYStrong muscles, tendons, and ligaments help to prevent injury both at work and play.Helps with weight loss by increasing lean muscle mass, thereby increasing metabolic rate.

• Use it or lose it – muscle atrophy



FLEXIBILITYFLEXIBILITY Ability to bend or extend without injury;Depends on the elasticity of the muscles, tendons, and ligaments.Reduce risk of injury

Dynamic stretches – hold for 5 sec but repeatStatic stretches – hold stretch 20-30 sec

Lengthen tissues without injuryLong-lasting, painless, pleasurable stretches.

After a light warm-up – blood in musclesStretch at the end of your activity





EnduranceEnduranceAbility to sustain an effort for a long time.

Muscle endurance: the ability of a muscle to contract repeatedly within a given time without becoming exhausted

Cardiovascular endurance: the ability of the cardiovascular system to sustain elevated heart rate over a period of time (>20 mins). Heart is a muscle



Cardiorespiratory Endurance

Is increased by aerobic exerciseIt increases strength of heart, lung capacity and muscle strengthIncreases Stroke volume = amount of blood pumped per beatDecreases heart rate = rate at which heart must pump blood to tissues at rest

The more fit you are, the lower you heart rate

Increases the ability of muscle to use oxygen to produce energy



Body Composition

% Fat vs Lean Muscle

More fit = greater % lean body fat

Skinny does NOT equal fit – muscle adds weight

Dependent on age & sex

= 8 -19% body fat

= 21-32% body fat



Nutrition and Fitness linked - YES

‘I didn’t eat enough, I had no energy!!!’

’It was that we were exercising so much and not compensating with more food to fuel our bodies’.



Ingredients for Fitness

• Carbohydrates

• Protein

• Fat

ENERGY adenosine triphosphate (ATP)



Oxygen too!

• Aerobic = Metabolism with Oxygen Glucose, fatty acids and amino acids are completely broken down to form CO2 and H20 and to produce ATP.

• Anaerobic = Metabolism with No Oxygen ONLY glucose is metabolized in this way to produce ATP when oxygen cannot be supplied quickly enough to the tissues to support aerobic metabolism.

Anaerobic metabolism is also called anaerobic glycolysis.





Aerobic Metabolism Anaerobic metabolism

Oxygen required Oxygen not required

In theory, can continue forever Cannot continue indefinitely

Carbs, fat and protein used Only carbs used

Low- to moderate-intensity activities

High-intensity activities





• At Rest At Rest • muscle use mostly fat and some carbohydrates for energy• there is oxygen available

• During ExerciseDuring Exercise• the source of energy depends on oxygen and fuel availability



Aerobic – heart/lung can keep up with the muscles demand of oxygen – Long term

• Reaction occurs with oxygen and use fatty acids (adipose) and glucose (muscle)

• ATP produced slower but more efficient

• Improved lung capacity and a stronger heart, which boosts pumping efficiency and lowers the resting heart rate = CARDIOVASCULAR CONDITIONING

• Improved circulation and reduced blood pressure

MODERATE - walking, running, swimming, cycling



Anaerobic – heart/lung reached a limit – usually when start • Energy demand outstrips oxygen supply - short term

• Glucose principle source of energy – GLYCOLYSISGlucose = Pyruvate + electrons + 2x ATP + Lactic

Acid

• Muscle metabolizes its own limited stores of glycogen, glucose in bloodstream (from liver or diet)

• Fast and brief but inefficient (partial brake down of glucose – lactic acid is formed)

• Leads to increased speed and power in muscle

HIGHLY INTENSE ACTIVITIES – sprinting, jumping.

Heart rate is maximum



GLUCOSE & FATTY ACIDS

Fuels

ENERGY







For intensities in physical activities:

http://www.cdc.gov/nccdphp/dnpa/physical/pdf/PA_Intensity_table_2_1.pdf



• Glycogen then Fat – conserve glycogen supply

• Untrained Muscle• Glucose• Quick source of energy

• Trained muscle• Fat over glycogen• Conserve glucose• Avoid “hitting the wall”

Which Fuel also depends on duration and training



• Trained • Bigger & stronger heart• Increased stroke volume• More oxygenated blood

reaching muscles• Increased ability to store

glycogen• Increased number & size of

mitochondria – where aerobic metabolism occurs

• Increase fat burning enzymes and fatty acid burn for ATP and spare glycogen

EQUALS exercise longer and harder



Which Fuel?• Depends on intensity, duration and frequency, also the

characteristics of the exerciser

• The general proportion of energy for athletes and healthy individuals should be:

§ 45-65% total energy from Carbohydrates – complex carbs§ 20-35% from fat – good fats§ 10-35% from protein – for muscle repair

25-30 pounds - body fat (unlimited); 1 pound carbohydrate (limited)



• Muscle burns fat from all fatty deposits

• Fat source is unlimited unlike carbohydrate but oxygen must be present

• Conversation test = talk while exercising = fat burnLow – moderate intensity

• Training improves body’s ability to deliver fat to working muscles and have the enzymes needed

• Triglycerides – fatty acids – energy.

Fat as Fuel



• Fit people = more muscle than fat

• Exercise requires muscle - largely made up of proteins

• 5-10% of energy for weightlifters and endurance sports• Increased muscle mass• Increased red blood cells to carry oxygen• Increased amounts of aerobic enzymes

• DURING exercise – Muscle protein breakdown - Free amino acids – liver – glucose – ENERGY

• AFTER exercise – Muscle growth and repair = protein build up

• More protein intake without exercise = bigger muscles – NO!

Protein



Ingredients for Fitness

• Water

• Vitamins

• Minerals



• YES!

• You sweat = lose fluid

• Drinking fluid • before • during• after exercise.

• Ignoring body fluid needs can hinder performance and increase risk of heat-related injury.

Water



• Dehydration = loss of water• Decrease blood volume • Decrease oxygen and nutrients to muscle• Decrease blood flow to skin, reducing

sweating and cooling

• HEAT CRAMPS – loss of sodium and potassium• HEAT EXHAUSTION – weak pulse, low blood

pressure, fainting, sweating profusely• HEAT STROKE – require medical treatment

Water



Water

• Hyponatremia• Reduction in sodium in

blood• Too much water• Too much sweat and

losing sodium but replacing with water

• Diluting sodium• Swelling



• Water is fine

• Endurance events – longer than 60 mins – consider Fluid Replacement Drinks

• Enhance the body’s use of carbohydrate and water.

• Carbohydrate in a sports beverage serves 3 purposes during exercise:

• Energy source for working muscles. • Helps maintain blood glucose• Helps increase the rate of water absorption from the

small intestine, helping maintain plasma volume.

Water or Sports Drinks?



• Maintenance and growth of healthy bonesCalcium

•Transport nutrients and oxygen to and within cellsIron

•Catalyst for enzymesMagnesium

•Muscle contraction and nerve transmissionsSodium, Potassium

•Fluid BalanceSodium

What do Minerals do?



• Links and regulators of energy-producing and muscle building pathways

• Ensure muscle is able to convert food energy to body energy and important for muscle protein formation

• Energy producing reactions in metabolism – Vitamin B

• Enhance recovery – antioxidants – Vitamin E & C

• Important for bone and joint structure – Vitamin D & A

What do Vitamins do?



49



• Iron Deficiency – endurance athletes & menstruating females• Lose from sweat• Inadequate dietary intake• Increased plasma volume – dilute iron concentration = SPORTS

ANEMIA• Lack of OXYGEN to working muscles

• Calcium Deficiency• Important in bone development• Weak bones = Stress Fracture

• Amenorrhea• Excessive exercise leads to cessation of menstruation –

need estrogen• Lack of diet + amenorrhea + low bone density = ATHLETE

TRIAD

Deficiencies with Exercise



• Carbo-loading - endurance

• Before Exercise• High Carb – 2-4 hours before

• During Exercise• Fluids- sports drinks - electrolytes• Energy gels – Carbs

• After Exercise• Replenish fluids, electrolytes, glycogen• Amino Acids/Protein for repair

Food/Fluids to Maximize performance



• Ergogenic Aids • Ergo = work; Genic = give rise to

• Costly versions of vitamins/minerals/sugars that you get from a WELL BALANCED DIET

• Except for IRON, vitamin and mineral deficiencies are rare among athletes – provided they eat a WELL BALANCED DIET

• Protein Supplements have not been shown scientifically to increase muscle size

• Anabolic Steroids – synthetic hormones = dangerous

• Caffeine – glycogen sparing – but need to exercise 1.5-2 hrs; diuretic

• Beer – carbohydrate – diuretic, high calories, depress nervous system

Supplements – will they make you a better athlete?



Foundation of good athletic performance

=

Talent, hard work, healthy diet**Healthy diet is one supplying right number of kCalories;

proper balance of carbohydrates, protein, fats; water; rich in whole grains, fruits and vegetables; high in fiber; moderate fat

& sodium; low in added sugar.

ENJOY A BALANCED DIET



COOL DOWN



55

• At least 60 min/session of Physical Activity – 3-5 times a week

• Well Balanced Diet

• Stretching/Flexibility

• Reduced chronic diseases

• Happy, healthy lifestyle



• Walk 30 mins

• Eat a Well Balanced Diet

• Do Some Stretching

• MOVE!!! Be Active!

Homework

Documents

Nutrition & Fitness Lecture 17 March 26, 2015 Dr. Quadro Mens sana in corpore sano Roman poet Juvenal