Lecture 11

Exercise During Fasting

• Fasting for about 16 hours can increase fat oxidation.
• Endurance performance is diminished because of glycogen depletion
• Endurance athletes should avoid high intensity training while fasting.

Testing: Tenets and Purpose

• Testing involves a standardized process of measuring physiological parameters to assess fitness, function, and health.
• It follows a systematic schedule of assessments to provide ongoing information about an athlete's status.
• Tests must stress the athlete sufficiently to reveal physical/physiological limitations.
• Testing should provide an objective, reliable, safe, and valid assessment of a person's capacity for physical effort.
• Testing should include medical screening (PARQ) to assess family, injury, and health history.
• The specific tests used are population dependent.

Populations for Testing

• Athletic (sport-specific testing)
• General populations
• Clinical populations
• Functional populations
• Other distinct populations (elderly, cardiac rehab, pediatric, industrial).
• Appropriate tests should be selected for each populations, based on test objectives and exercise prescriptions.

Athlete Testing: Reasons

• To predict performance and test for sport-specific fitness.
• To assess safety in competition by evaluating strength levels, strength balance, and joint structure.
• To assess the efficacy of training during off-season, pre-season, or in-season.
• To assess athlete compliance from off-season to pre-season.
• To assess presence of overtraining during the season.

General Population: Reasons

• To evaluate functional fitness (strength and endurance for everyday tasks).
• For specific fitness assessments of cardiorespiratory, musculoskeletal, and neuromuscular function.
• To assess cardimetabolic health, predict mortality risk, and detect presence or severity of disease.
• To predict disease outcomes (prognosis).

Athlete Testing: Methods

• Cardiorespiratory endurance is assessed by VO2 max measurements and aerobic/anaerobic performance tests (BEEP test, Cooper run).
• Muscle strength is assessed by load x reps (standards), considering absolute vs. relative strength.
• Speed/power are evaluated using specific tests
• Body composition is measured using underwater weighing or DEXA.

General Population: Methods

• Cardiorespiratory endurance is assessed via predicted or measured values (submax vs max testing) such as Cooper run or VO2 max test.
• Functional fitness (including balance) is assessed via chair test.
• Muscle strength is assessed via 1 RM protocol + Bryzcki equation, relative strength, and strength balance.
• Body composition is assessed via BMI, waist circumference, SOS, and bioimpedance, including bone density.
• Clinical status is assessed using an integrated approach (risk factor assessment).

Functional Fitness

• The primary goal is to improve fitness for everyday tasks using movement patterns that mimic everyday movements.
• Exercises should be complex (multi-joint) or multiplane (bidirectional).
• Minimal equipment should be used.
• There should be no focus on individual parts that work independently (unless addressing asymmetries).

Exercise Stress Test

• An assessment of cardiovascular system function, and ability to support metabolic needs of exercise.
• It takes place in a clinical environment with cardiologist present.
• The goal is to stress the system and detect adverse responses.
• A progressive walking test is used, often the Modified Bruce Protocol
• An 11-lead ECG monitors for cardiac stress, such as ST-segment depression, and arrhythmias (atrial or ventricular).
• Blood pressure is monitored for signs of collapse (decrease in systolic or diastolic blood pressure).

Testing: Objectivity

• Objectivity means results are not influenced by personal feelings or opinions.
• To ensure objectivity, all tests should be performed by qualified or independent personnel.
• All results should be interpreted based on observable phenomena, uninfluenced by emotions or prejudices (= unbiased).
• All tests should be "critical" in nature - testing fitness, strength, function, and health.

Testing: Reliability

• A test is considered reliable only if the results are "reproducible," repeatable from test to test, regardless of who conducts the test.
• High reliability assures that detected changes are real changes, not due to measurement error originating in equipment or personnel.
• Intrinsic vs extrinsic factors affect reliability.
• Controlling what you can maximize on the reliability of any test

Reliability: Intrinsic Factors

• Sources of error the athlete "brings"
• Diet
• Recreational drugs
• Ergogenic aids
• Alcohol use
• Sleep deprivation
• Caffeine ingestion
• Effort/motivation
• Experience
• Injuries
• Health/sickness/disease
• Congenital vs disease

Reliability: Extrinsic Factors

• Source of error due to measurement error or variability
• The key to reducing extrinsic error is knowledge, experience, and competence.
• Follow standardized test protocols.
• Choice of tests and test order
• Calibration of equipment
• Environmental conditions
• Personnel and audience
• Athletes clothing
• Warm up and recovery
• Fluid and food intake
• Prescribed drugs
• Scheduling (time of day)

Testing: Specificity

• Know what the athlete needs wrt fitness standards for their sport, position, or role.
• It is important to test what the athlete needs.
• Standard test/scores are available for most sports.
• Be aware of sport-specific needs and requirements.
• Remember that off and in seasons fitness goals can vary.
• Testing procedure and priorities should be specific.

Testing: Validity

• A test result is valid if it measures what it is supposed to measure.
• The test must stress the target system in a meaningful way: aerobic energy/fitness (and anaerobic), strength/power/flexibility/balance.
• Knowledge of the various tests is crucial.
• An invalid test is just exercise.

Testing: Relevance

• Athlete fitness testing is important for many reasons, but competition is still the ultimate test of game fitness (for coaches).
• Individual differences exist wrt how important a given attribute may impact performance.
• Some aspects of fitness are more important than others.
• Do not over interpret

World Superstars

• Brian Budd won world superstarts 3 times
• Phil Kessel, although not super fit, is very fast in the NHL.
• Mike Mamula was an NFL combine legend.
• Tony Mandarich was a strong offensive lineman in college but less successful in the NFL.
• George Best had low strength but was one of the best in Europe.
• Wayne Gretzky was skinny and short, refused to lift weights but was very fit

Athlete Testing: When?

• Consider what is adequate vs. what is realistic.
• The reason for testing dictates the frequency and complexity.
• Why are you testing?
• What and who are you testing?
• Multi-athlete teams vs. individuals
• Field test vs single athlete tests
• Other complicating issues to consider are money, equipment, time, contracts, and unions.

ACSM Risk Stratification for Testing

• Low risk: Asymptomatic females and males who have < 2 risk factors.
• Testing should stop when the patient reaches 15 on RPE scale and >70% MHR.
• Risk is higher for extreme vs. moderate endurance exercise
• Males are more susceptible than females
• Blacks are more susceptible than hispanics and caucasians.
• Basketball > soccer = football

SADS (Sudden Arrhythmic Death Syndrome)

• The sudden and unexpected death of a "healthy" individual during exercise or sport (within 4 hours).

Cardiomyopathy and SADS

• Main causes of SADS: 33% due to occult cardiac disorders, 20% due to commotio cordis, and 20% due to coronary heart disease.
• Commotio cordis is sudden arrhythmic death caused by chest wall impact, occurring most often in athletes between ages 8-18 playing sports with projectiles (hockey, baseball).

Drugs and SADS

• Collapsed at resident due to cardiac arrest following cocaine use
• Gijs Verdick: Double heart attack
• Tom Simpson died in the 13th stage of the Tour de France.

Exercise-Induced Hyperthermia

• The body produces or absorbs heat during exercise leading to failure of thermoregulatory mechanisms, causing a core temperature climb uncontrollably.
• Core temperature exceeds 40 degrees, which may lead to encephalopathy (alteration of brain structure/function), confusion, convulsions, or coma.
• Hyperpyrexia occurs when core temperature is set above 40 degrees, allowing a fever state.
• Dangerous exercise x heat
• Interaction with drugs
• Ecstasy or fentanyl increases probability

2007 Chicago Marathon

• 49 people were hospitalized.
• Chad Schieber (35) collapsed and died of cardiac arrest at mile 18.
• The race was called off at 11:30 a.m.

Cardiomyopathy and SADS (Age)

• Known vs occult?
• 35 years = CAD

Occult Cardiac Disorders (OCD)

• These are undiagnosed congenital defects that may not produce exercise intolerance.
• The first symptom is often sudden death (detected via genetic screening).
• The main occult cardiac disorder is familial cardiac hypertrophy (FCH), the leading cause of sudden cardiac death < 35 years.
• Incidence of FCH is ~1 in 500 (= 0.2% pop).
• Impaired contractility leads to compensatory hypertrophy.
• Penetrance of the disease is variable.
• May eventually cause ventricular fibrillation.

What Are They?

• Arrhythmia (general)
• A generic term for any abnormal electrical activity
• Can be non-pathological
• Includes fibrillations (atrial or ventricular)
• Atrial fibrillation can be a chronic condition, treatable.
• Ventricular fibrillation is a common cause of cardiac arrest, fatal if not reversed by defibrillation (actuely)
• Examples of sudden athletic death due to OCD