KIN210 exam #3

Chad Wiggins MSU Kin210

What happens to systolic blood pressure (SBP) during graded exercise?

"SBP increases proportional to exercise intensity. At submaximal exercise it rises gradually and plateaus at steady state. At maximal exercise it can rise to 180–220 mmHg."

What happens to diastolic blood pressure (DBP) during exercise?

"DBP slightly decreases or remains stable during submaximal exercise. At maximal exercise it may slightly increase."

What is MAP and how is it calculated?

"MAP = Mean Arterial Pressure. Formula: MAP = Cardiac Output (Q) × Total Peripheral Resistance (TPR). During exercise

What is the a-vO2 difference?

"The difference in oxygen content between arterial blood and venous blood. It tells you how much O2 was extracted from blood on one pass through the circulation. Formula: CaO2 − CvO2."

What is the a-vO2 difference at rest?

"~7 mL/100 mL (~40% O2 extraction). Arterial O2 = ~18 mL/100 mL; Venous O2 = ~11 mL/100 mL."

Which side of the a-vO2 difference changes most during exercise

and why?

What is the Fick Equation?

"VO2 = Cardiac Output (Q) × a-vO2 difference. Where Q = HR × SV."

What are resting values for HR

60-100bpm

What are maximal values for HR

195-200bpm

What is minute ventilation (VE) and how is it calculated?

"VE = total air moved in and out of the lungs per minute. Formula: VE = Tidal Volume (TV) × Breathing Frequency (f)."

How does tidal volume change during exercise?

"Rises first and fastest at low-to-moderate intensities — from ~0.5 L at rest to ~3 L at hard exercise. Plateaus around 3 L and cannot increase further (ceiling effect)."

How does breathing frequency change during exercise?

"Increases throughout exercise

What is the primary driver of increased ventilation during exercise?

"Rising CO2 is the biggest driver. Others: increased H+ (acidosis)

What is the bicarbonate buffer system?

"The immediate chemical defense against H+ accumulation. H+ + HCO3− → H2CO3 → H2O + CO2 (exhaled). H+ is converted into CO2 that is breathed out. Acts within seconds."

Why is active recovery better than passive recovery after high-intensity exercise?

"Active recovery (~30–40% max HR) maintains blood flow to muscles,

What is EPOC?

"Excess Post-Exercise Oxygen Consumption — elevated oxygen consumption that continues after exercise stops while the body restores itself to its pre-exercise state."

How long does EPOC last?

"Depends on intensity: Light/moderate = 10–30 min. High intensity = 1–3 hours. Very high intensity/prolonged = up to 24+ hours."

What direction does VO2 move at the end of exercise during EPOC?

"It decreases — dropping quickly at first (fast component) then tapering slowly (slow component) back to baseline."

What does FITT stand for?

"Frequency (how often), Intensity (how hard you work), Time (how long), Type (which kind of exercise).” This acronym is used to guide the development of effective exercise programs.

What is progressive overload?

"Systematically increasing the demand placed on the body over time to continue stimulating adaptation. Applied by gradually increasing one or more FITT variables."

What are the physical activity guidelines for adults (18–65)?

"Moderate aerobic PA ≥30 min on 5 days/week OR vigorous ≥20 min on 3 days/week (or combination). Key target: 150 min/week moderate. Strength training ≥2 days/week. Bouts of ≥10 min count."

What is the Borg RPE Scale?

"A scale from 6–20 measuring subjective perceived exertion during exercise. Multiply score × 10 to estimate heart rate (e.g. RPE 15 ≈ 150 bpm). Used when HR monitors are unavailable or to standardise effort across individuals."

How do you calculate target heart rate using % HRmax method?

"Step 1: HRmax = 220 − age. Step 2: THR = HRmax × desired intensity %. Example (age 23,

How do you calculate target heart rate using % HRreserve (Karvonen) method?

"Step 1: HRmax = 220 − age. Step 2: HRR = HRmax − HRrest. Step 3: THR = (HRR × intensity%) + HRrest. More accurate than % HRmax — accounts for resting HR."

What is a MET?

"Metabolic Equivalent of Task. 1 MET = 3.5 mL O2/kg/min (resting metabolic rate) ≈ 1 kcal/kg/hour. An activity at 6 METs uses 6 × 3.5 = 21 mL O2/kg/min."

How do you calculate calories burned using METs?

"Calories = MET × body weight (kg) × time (hours). Example: 8 METs, 160 kg, 1 hour = 1280 calories.

What is the aerobic exercise prescription for adults (18–65)?

"Frequency: 3–5 days/week. Intensity: 50–90% VO2max / 40–90% HRR / RPE 12–16. Time: 20–60 min/day (bouts ≥10 min OK). Type: continuous aerobic

What are the 4 components of an endurance training session?

"1. Warm-up (5–10 min,

How does resting HR change after endurance training?

"Decreases — from ~70–75 bpm (untrained) to ~40–60 bpm (trained). Called training bradycardia. Drops ~1 bpm per week of training. Increased vagal tone and higher SV mean fewer beats needed to maintain cardiac output."

How does resting cardiac output change after endurance training?

"No change — stays ~5 L/min. Same output achieved with fewer

How do HR

SV

How does maximal HR change after endurance training?

"It does NOT change — remains ~195–200 bpm. This is a key exam point. Athletes ~190 bpm vs normal ~195 bpm — essentially the same."

How does maximal stroke volume change after endurance training?

"Increases dramatically — from ~112 mL/beat (untrained) to ~205 mL/beat (trained). This drives the large increase in maximal cardiac output."

What drives the increase in maximal cardiac output after endurance training?

"Entirely driven by increased maximal stroke volume (SV). Maximal HR does not change."

What is the lactate threshold (LT)?

"The exercise intensity at which blood lactate begins to accumulate faster than it can be cleared — marking the shift from predominantly aerobic to anaerobic energy supply."

How does the lactate threshold change after endurance training?

"Shifts to the right — occurs at a higher % of VO2max and higher absolute intensity. Due to: decreased lactate production

How does lifelong endurance training affect muscle fiber distribution?

"Promotes Type I (slow oxidative) fiber distribution — up to ~70% vs ~50% in sedentary adults. Type IIx fibers nearly absent — converted toward IIa and eventually Type I over decades."

What is essential fat and what % do men and women have?

"Fat required for normal physiological function (nerves

What is storage fat and why is some of it beneficial?

"Fat stored in subcutaneous and visceral adipose tissue. Benefits: energy reserve

What is the energy balance equation?

"Weight change = Energy IN (kcal consumed) − Energy OUT (kcal expended). IN = OUT → stable weight. IN > OUT → weight gain. IN < OUT → weight loss. ~3

What makes up total daily energy expenditure?

"RMR (resting metabolic rate) = 60–70%. Physical activity = 20–30%. Thermic effect of food = ~10%."

What principle do hydrostatic weighing and the Bod Pod use?

"Archimedes' principle — a body displaces a volume of water (or air) equal to its own volume. Fat is less dense (floats)

What is the difference between hydrostatic weighing and the Bod Pod?

"Both use Archimedes' principle. Hydrostatic weighing uses water submersion. Bod Pod uses air displacement in a sealed chamber — more comfortable

What is DXA and why is it the gold standard?

"Dual-Energy X-ray Absorptiometry — uses two low-dose X-ray beams to distinguish bone mineral

What is BIA and what is its main limitation?

"Bioelectrical Impedance Analysis — sends a painless electrical current through the body. Fat resists electricity; lean tissue conducts it. Main limitation: highly sensitive to hydration status — results vary with dehydration

What is the BMI formula and its categories?

"BMI = weight (kg) ÷ height² (m²). Underweight: <18.5. Normal: 18.5–24.9. Overweight: 25–29.9. Obese: ≥30."

What are the warnings/limitations of BMI?

"Does not measure body fat directly. Cannot distinguish fat from muscle (muscular athlete may be 'obese'). Cannot identify fat location (visceral vs subcutaneous). Does not account for age

What is a hazard ratio?

"A measure of relative risk. HR = 1.0 means same risk as the reference group. HR > 1.0 = higher risk. HR < 1.0 = lower risk. The relationship between body fat and all-cause mortality is U-shaped — both underweight and obese carry elevated hazard ratios."

What is the difference between muscular strength and muscular power?

"Strength = maximum force a muscle can produce in a single effort (measured by 1RM). Power = force per unit of time (Power = Force × Velocity). Strength is how much; power is how fast that force is applied."

What neural adaptations occur in the first 1–8 weeks of resistance training?

"1. Increased motor unit recruitment. 2. Improved motor unit synchronisation. 3. Increased firing rate (rate coding). 4. Reduced neural inhibition. 5. Improved intermuscular coordination. Little to no visible muscle size change during this phase."

What hypertrophy adaptations occur after 8–10+ weeks of resistance training?

"1. Myofibrillar hypertrophy (more actin/myosin). 2. Sarcoplasmic hypertrophy (more fluid/glycogen). 3. Increased fibre cross-sectional area (Type II especially). 4. Satellite cell activation. 5. Connective tissue adaptations (stronger tendons/ligaments)."

What is muscle atrophy?

"A decrease in muscle size — specifically reduction in cross-sectional area of muscle fibres

How fast is strength lost during immobilisation and how long to regain it?

"3–4% per day in the first week of immobilisation. ~10–15% per week after 2 weeks of detraining. Time to regain: approximately 2× the detraining period. Muscle memory (retained satellite cell nuclei and motor patterns) speeds retraining."

What is the FITT prescription for muscular strength (novice)?

"Frequency: 2–3 days/week. Intensity: 60–70% 1RM. Sets: 1–3. Reps: 8–12. Rest: 2–3 minutes between sets (allows full ATP-PCr replenishment). 8–10 exercises targeting all major muscle groups."

What rest period is used for muscular endurance training and why?

"≤30 seconds between sets. Short rest deliberately fatigues the muscle — training it to sustain repeated efforts. Reps: 15–25+. Intensity: <67% 1RM."

What rest period is used for hypertrophy training and why?

"30–90 seconds between sets. Maintains metabolic stress

What rest period is used for power training and why?

"2–3 minutes between sets (full recovery). Needed so each rep can be performed at maximum speed. Fatigue kills power output. Intensity: 30–60% 1RM performed explosively. Reps: 3–6."

Which heat loss mechanism dominates during exercise?

"Evaporation — accounts for up to ~80% of heat loss during exercise. Sweat evaporating from skin carries heat away. Critically impaired by high humidity (sweat cannot evaporate when air is already saturated)."

Which heat loss mechanism dominates at rest?

"Radiation — emission of infrared heat from warm skin to cooler surroundings. Accounts for ~60% of heat loss at rest. Requires no physical contact."

What is the difference between conduction and convection?

"Conduction = direct heat transfer by physical contact with a solid (e.g. ice vest

What brain structure regulates body temperature?

"The hypothalamus — acts as the body's thermostat. Detects changes in core temperature and sends signals to skin and skeletal muscle to either dissipate or conserve heat."

What does the hypothalamus do in response to heat?

"Triggers: (1) Cutaneous vasodilation — skin blood vessels dilate to bring heat to surface. (2) Sweating via eccrine glands — evaporation is the main cooling mechanism. (3) Reduces skeletal muscle motor drive in extreme heat. (4) Drives behavioural responses (seek shade

What does the hypothalamus do in response to cold?

"Triggers: (1) Cutaneous vasoconstriction — redirects blood to core. (2) Piloerection (goosebumps). (3) Shivering thermogenesis in skeletal muscle — generates heat 2–5× above resting. (4) Drives behavioural responses (seek warmth

How do HR and SV change during exercise in the heat compared to thermoneutral (before acclimation)?

"HR is HIGHER — compensating for reduced venous return. SV is LOWER — blood pools in dilated skin vessels

Why does cardiac output decrease during exercise in the heat?

"Blood is diverted to the skin for cooling

What are the symptoms of heat cramps?

"Painful

What are the symptoms of heat exhaustion?

"Heavy sweating, weakness, dizziness, headache, nausea, and cool, clammy skin.”

What are the symptoms of heat stroke and why is it life-threatening?

"Hot

What is the key clinical difference between heat exhaustion and heat stroke?

"Heat exhaustion: still sweating

What strategies help endurance athletes competing in heat?

"Pre-cooling (ice vest/cold water immersion before event). Slower early pacing. Aggressive hydration with electrolytes (sweat rate 1–2 L/hr). Heat acclimatisation 9–14 days prior. Schedule in cooler hours (morning/evening)."

How does heat strategy differ for sprint vs endurance athletes?

"Sprints: anaerobic performance largely unaffected by heat. Less need for pre-cooling. Cool between heats. Stay hydrated across competition day. Endurance: much more affected — cardiovascular competition for skin blood flow degrades performance significantly. All major strategies (pre-cooling

Why does exercise performance decline at altitude?

"PO2 decreases (fewer O2 molecules per breath despite same 20.93% O2 fraction). Haemoglobin cannot fully saturate → arterial O2 content (CaO2) falls → less O2 delivered to muscles → VO2max decreases. Maximal cardiac output does not change — it is O2 content of blood that falls."

At what altitude does performance start to be impaired?

"Above ~1,500m”

What are the immediate physiological responses upon arriving at altitude?

"1. ↑ Ventilation (hyperventilation — peripheral chemoreceptors detect low PO2). 2. ↑ HR (sympathetic response to low O2 delivery). 3. ↑ Haematocrit short-term (plasma loss/diuresis

Why do the kidneys excrete bicarbonate at altitude?

"Hyperventilation blows off CO2 → blood becomes more alkaline (respiratory alkalosis). Kidneys excrete HCO3− (bicarbonate) in urine to restore normal pH. This also causes fluid loss (diuresis) and reduces plasma volume."

How does altitude affect the O2 diffusion gradient into skeletal muscle?

"Sea level: arterial PO2 ~100 mmHg

What is EPO and what triggers its release?

"Erythropoietin (EPO) — a hormone released by the kidneys (and partly liver) in response to hypoxia (low O2). Triggers: reduced PO2 at altitude → kidneys detect low O2 → release EPO into bloodstream."

What does EPO do and why does it benefit endurance athletes?

"EPO stimulates bone marrow to produce more red blood cells (erythropoiesis). New RBCs take 2–3 weeks. Result: ↑ RBCs → ↑ haemoglobin → ↑ O2-carrying capacity → ↑ CaO2 → ↑ VO2max. Athletes returning to sea level have more RBCs than untrained sea-level athletes — endurance advantage."

What is the live high

train low strategy?

Does anaerobic/sprint performance decline at altitude?

"No — largely unaffected. May even slightly improve due to reduced air resistance. Only aerobic/endurance performance is impaired by altitude hypoxia."

What is the PO2 at sea level?

"PO2 = 0.2093 × 760 mmHg = ~159 mmHg. At altitude