Heart Rate
● Cardiac cycle: indicates exercise intensity or exertion/demands on the body (central)
● Resting heart rate affected by:
○ Fitness status
○ Environment, temperature
○ Body position
■ Supine position will result in lower HR
○ Prior eating/exercise
■ Thermal effect of food (digestion process itself requires energy
expenditure)
■ Anticipatory response
○ Drugs (alc, caffeine)
■ Increase
○ Fatigue/overtraining
■ Increase resting HR
■ Decrease maximal HR
■ Difference between these two = HR reserve
○ Emotional stress
■ Increase for all emotional responses (positive or negative)
● Resting heart rate is not necessarily affected by how physically fit you are, affected more
by other factors ↑
● Differences between demographics
○ Males usually lower resting HR than females
■ M = 60-70 BPM; F = 70-80 BPM; Average population = ~72 BPM
○ Size/Age/Fitness
■ Bradycardia = <60 BPM; Tachycardia = >100 BPM
● “Brady” = slow; “Tachy” = fast
● Age-predicted max HR (don’t use the 220-age formula)
○ 208 - (0.7 x age) = predicted HR max
● Steady State HR
○ HR doesn't change more than 5 bpm within the time window of interest (won’t
experience this until minute 3-5)
Blood Pressure
● Effect of acute exercise on BP
○ Aerobic exercise — elevates systolic pressure, but has little effect on diastolic
pressure
○ Isometric exercise — intrathoracic pressure dramatically increases, decreasing
venous return to the right atrium and putting a great load on the ♥
● What to expect of BP with exercise
○ TM exercise expect SBP to increase 10 mmHg w/ each MET increase
○ If SBP increases greater than 20 mmHg with 1 MET increase in work — signals
hypertensive response (possible ♥ disease)
○ SBP should not drop, if it does then stop
○ DBP should remain consistent
● BP Procedures during exercise
○ Support the subject’s arm while cycling or walking
○ Good idea to mark the spot on the skin where stethoscope will go (use pen)
○ Allow the pressure to fall faster (6 mmHg a second)
■ This is because HR is faster
○ Take BP the last 30 seconds before the next stage (never record EKG or HR at
the same time as BP)
● Double product (Rate pressure product)
○ Estimation of the increased metabolic demand placed on the ♥
○ Formula: HR x SBP
○ Exercise increases both HR and SBP
○ Double product 5x higher at Max
○ Used as a guideline to prescribe exercise intensity in cardiac rehab — stable
angina
■ Should stay around 30,000 after ♥ surgery
○ Normal peak RPP should be between 25-40,000
● Arm vs leg exercise BP
○ Arm will raise BP higher than leg will
■ When muscles are activated, you are diverting blood flow to those
muscles
■ More blood flow to the arms means more BP
■ Lower body has more endurance than upper body (upper body muscles
are not as fatigue resistant)
■ More lactic acid in arms when exercising leads to more adrenaline leads
to higher BP
● IMportant BP values
○ Do not exercise if:
○ SBP > 160 mmHg at rest or
○ DBP > 100 mmHg at rest
○ Stop test if:
■ SBP >250 mmHg or
■ SBP doesn't rise or decreases with increase in work
■ DBP rise
■
● Physical fitness testing
○ Testing order
■ 1. Resting measures (BP, HR, Metabolism)
■ 2. Body composition only when normally hydrated… not sweating…
voided… fasted
■ 3. Dynamic warmup
■ 4. Cardiorespiratory fitness (submaximal)
■ 5. Muscular fitness (CV submax)
■ 6. Cardiorespiratory Fitness (maximal)
■ 7. Dynamic cool down (after maximal)
■ 8. Flexibility only when warm
EPOC: Excess post-exercise oxygen consumption
1 watt = 6 kgm/min
