1. Influence of Age and
Fitness on the Blood
Pressure Response
to Two Modes of
Dynamic Exercise
Dustin Grinnell
Physiology Department
Pennsylvania State University

2. Outline
• Scope of the Problem/Significance
– Aging and blood pressure
– Aerobic fitness and its influence on blood pressure in the aged
– Active muscle mass and the blood pressure response
• Background
– The blood pressure response to two modes of graded dynamic exercise
• Introduction
– To three main questions we proposed.
• Methods
– Proctor lab fitness study
• Results
– To three main questions
• Summary
– What age, fitness, gender and mode of exercise conclusions can we draw?

3. Aging and Blood Pressure
• It is well known that age is
associated with a rise in resting
and exercise blood pressure.
• Hypertension afflicts between
33 and 57% of men and 25 and
60% of women between ages
45 and 74.
• Resting:
• 20 mm Hg systolic and 10 mm Hg
diastolic increment increase in
blood pressure from age 30 to 65
years.
• Exercise:
• Many studies show that there is
a heightened blood pressure
response in the aged to graded
dynamic exercise.

4. Fitness and the Blood Pressure
Response in the Aged
• We know: age is associated with a higher resting and
exercise blood pressure
• Regular aerobic training
• Reduces systolic and diastolic blood pressure during rest
and sub-maximal exercise. The largest reduction occurs in
systolic blood pressure.
• Exercise training and hypertension
• For hypertensive older men and women, 9 months of low-
intensity, aerobic exercise lowered SBP by 20 mm Hg and
DBP by 12 mm Hg.

5. Blood Pressure and the Active Muscle
Mass
• Research has shown that the blood pressure
response to exercise is determined by the active
muscle mass.
• Relationship
• The magnitude of the pressor response is inversely related
to the size of the active muscle.
• Therefore the blood pressure response to the use of a
large muscle mass has been shown to be less pronounced
when compared to small.

6. Background
• Blood Pressure with Graded Exercise
– Systolic blood pressure: after initial rapid rise from resting level increases linearly with
exercise intensity.
– Diastolic blood pressure: remains stable or decreases slightly at higher exercise levels.
– During maximum exercise by healthy, fit men and women, SBP may increase to 200 mm
Hg or higher despite significantly reduced total peripheral resistance.
• The Pressor response
– The increase in blood pressure response to an exercise stress.
– We are defining it as the rise in blood pressure with increasing workload, or multiples of
metabolic rate (MET).

7. Background
• Graded Exercise Tests
– Can be used to evaluate functional capacity
– Usually given on a motorized treadmill or bicycle
ergometers.
– Workload intensity (how hard the subject is working)
is adjusted by progressively increasing the speed and
incline/resistance on the machine.
– The test starts at a low intensity and continues until a
prespecified workload is achieved physiologic
symptoms occur, or the subject is too fatigued to
continue.

8. Background
Large vs. Small Muscle Dynamic Exercise
Knee Extension Exercise
VO2max Test

9. Introduction
• Purpose:
• To explore the blood pressure responses to two modes
of dynamic exercise.
• Question #1
• Does aging affect the pressor response?
• How does the response compare between large and
small muscle exercise?
• Question #2
• Does fitness affect the pressor response in the aged?
• How does it compares across exercises?
• Question #3
• Is the pressor response determined by the active muscle
mass?

10. Methods
• Six groups of subjects recruited for “fitness study”:
• Younger men and women (20-30 yr)
• Older high and low fit men (60-79 yr)
• Older high and low fit women (60-79 yr)
• Non-obese, normotensive
• n= 5-10 per group
• All subjects performed:
• A large muscle exercise, a VO2max treadmill running test.
– Treadmill speed and incline is increased every three minutes until exhaustion.
• A small muscle exercise, a one-legged knee extensor exercise.
– Work rate is increased in a graded fashion (every 3 minutes, 5W and 10W
increments for women and men, respectively) until the participant cannot
maintain the knee kick cadence (40 kicks per minute).
• Variables recorded:
• Pulmonary gas exchange (VO2) using a metabolic cart
• Blood pressure via auscultation
• Heart rate via ECG

11. Question #1
Does aging affect the pressor response?
How does the response compare between large
and small muscle exercise?

12. Question #1: Results
Treadmill Exercise
Systolic Blood Pressure
Men Women
18 18
16 16
14 14
SBP Slope (SBP vs. MET)
SBP Slope (SBP vs. MET)
12 12
10 10
8
8
6
6
4
4
2
2
P = 0.03 P = 0.24
0
0
YW OW (LF)
YM OM (LF)
Age Group
Age Group
SBP
SBP

13. Question #1: Results
Treadmill Exercise
Diastolic Blood Pressure
Men Women
2.5 1.5
1.0
2.0
DBP Slope (DBP vs. MET)
DBP Slope (DBP vs. MET)
0.5
1.5
0.0
-0.5
1.0
-1.0
0.5
-1.5
0.0 -2.0
YM OM (LF) YW OW (LF)
Age Group Age Group
DBP DBP

14. Question #1: Results
Knee Kick Exercise
Systolic Blood Pressure
Men Women
35 35
30 30
SBP Slope (SBP vs. MET)
SBP Slope (SBP vs. MET)
25 25
20 20
15 15
10 10
5 5 P = 0.02
0 0
YM OM (LF) YW OW (LF)
Age Group Age Group
SBP SBP

15. Question #1: Results
Knee Kick Exercise
Diastolic Blood Pressure
Men Women
25 25
20 20
DBP Slope (DBP vs. MET)
DBP Slope (DBP vs. MET)
15 15
10 10
5 5
P = 0.13 P = 0.03
0 0
YM OM (LF) YW OW (LF)
Age Group Age Group
DBP DBP

16. Question #1: Results
• Question #1 – Age Effect?
• During large muscle exercise
• SBP - Old men show a heightened SBP response compared
to young men. No significant difference in women.
• DBP - Both sexes show no age difference in DBP response.
• During small muscle exercise
• SBP - Old women show a heightened SBP response
compared to young women. No significant difference in
men.
• DBP – old women show a greater DBP response compared
to young women. No significant difference in men.

17. Question #2
Are the heightened BP responses in older individuals fitness
dependent?
Does an increase in fitness level normalize or “correct” the
heightened blood pressure response seen in older men and
women?
How does it compare across exercises?

18. Question #2: Results
Treadmill Exercise
Systolic Blood Pressure
Men Women
18 18
16 16
14 14
SBP Slope (SBP vs. MET)
SBP Slope (SBP vs. MET)
12 12
10 10
8 8
6 6
4 4
2 2
P = 0.20 P = 0.20
0 0
OM (LF) OM (HF) OW (LF) OW (HF)
Fitness Level Fitness Level
SBP SBP

19. Question #2: Results
Treadmill Exercise
Diastolic Blood Pressure
Men Women
2.5 1.0
0.5
2.0
DBP Slope (DBP vs. MET)
DBP Slope (DBP vs. MET)
0.0
1.5
-0.5
1.0
-1.0
0.5
-1.5
0.0 -2.0
OM (LF) OM (HF) OW (LF) OW (HF)
Fitness Level Fitness Level
DBP DBP

20. Question #2: Results
Knee Kick Exercise
Systolic Blood Pressure
Men Women
40
35
30
SBP Slope (SBP vs. MET)
30
SBP Slope (SBP vs. MET)
25
20
20
15
10
10
5
P = 0.15
0 0
OM (LF) OM (HF) OW (LF) OW (HF)
Fitness Level Fitness Level
SBP SBP

21. Question #2: Results
Knee Kick Exercise
Diastolic Blood Pressure
Men Women
16 25
14
20
DBP Slope (DBP vs. MET)
DBP Slope (DBP vs. MET)
12
10
15
8
6 10
4
5
2
P = 0.004 P = 0.13
0
0
OM (LF) OM (HF)
OW (LF) OW (HF)
Fitness Level
Fitness Level
DBP
DBP

22. Question #2: Results
• Question #2 – Fitness Effect?
• During large muscle exercise
• SBP - Both low fit older men and women exhibited greater
SBP responses compared to high fit, but not statistically
significant.
• DBP - Both sexes show no fitness effect in DBP response.
• During small muscle exercise
• SBP - Both sexes show no fitness effect in SBP response.
• DBP – low fit old men show a much higher DBP response
when compared to high fit older men. No difference in
women.

23. Question #3
Is the pressor response determined by the
active muscle mass?
I.e. is the pressor response heightened with
the knee extensor exercise vs. the
treadmill?

24. Question #3: Results
Systolic Blood Pressure
Men Women
35 40
30
SBP Slope (SBP vs. MET)
SBP Slope (SBP vs. MET)
30
25
20
20
15
10
10
5
0 0
YM OM (LF) OM (HF) YW OW (LF) OW (HF)
Age Group Age Group
Treadmill Treadmill
Knee Kick Knee Kick

25. Question #3: Results
Diastolic Blood Pressure
Men Women
25 25
20 20
DBP Slope (DBP vs. MET)
DBP Slope (DBP vs. MET)
15 15
10 10
5 5
0 0
YM OM (LF) OM (HF) YW OW (LF) OW (HF)
Age Group Age Group
Treadmill Treadmill
Knee Kick Knee Kick

26. Question #3: Results
• Question #3 – BP Response determined by the active
muscle mass?
• SBP – significant mode-specific response, i.e. SBP response
was more pronounced during small muscle knee kick
exercise compared to the large muscle treadmill running
exercise.
– Except for young women group.
• DBP – Significant mode-specific response.
– Except for high fit older men.

27. Summary
• Question #1: Age Effect
– SBP - Heightened exercise SBP only with old men during treadmill and
old women during the knee kick exercise.
– DBP – Greater DBP response only seen in old women during the knee
kick exercise.
• Question #2: Fitness Effect
– SBP – no fitness effect for both sexes and both exercises.
– DBP – Heightened exercise DBP only in older men during knee kick
exercise.
• Question #3: Size of the active muscle mass
– The pressor response during small muscle exercise, during knee
extension, exceeded the response seen in exercise using many large
muscles, during treadmill running.
• SBP – except for young women.
• DBP – except for high fit older men.

28. Acknowledgements
Research Team
David Proctor, PhD (PI)
Joaquin Gonzales, PhD (Postdoc)
Sandy Smithmyer (Study Coordinator)
Julie Miedlar (Doctoral Candidate)
Collaborators
GCRC (University Park, Hershey)
Funding
Training Grants in Physiology, Seed Grant in
Gerontology Gerontology