Human Development and Aging Physiology

Question 1

Why is the resting and exercise HR higher in children?

Answer 1

To compensate for lower stroke volume and Q relative to body mass.

Question 2

How do children compensate for higher Q at any given sub-maximal workload when compared to adults who maintain lower Q?

Answer 2

Increased O2 extraction from increased blood flow through skeletal muscle.

Question 3

True or False; blood pressure is higher in children compared to adults?

Answer 3

False

Question 4

Briefly describe how exercise capacity and VO2 max increases during childhood? (3)

Answer 4

1. Accelerated during puberty/ growth spurt periods.
2. Androgen-induced hypertrophy of heart/ hemoglobin production, which facilitates O2 delivery.
3. Increased skeletal mass increases O2 extraction.

Question 5

When does peak bone mass occur?

Answer 5

Both sexes by 25-30 years

Question 6

How can normal bone growth be disrupted? (3)

Answer 6

1. Excessive strenuous exercise due to epiphysis not yet united with bone shaft.
2. Epiphysitis due to overuse.
3. Fractures passing through epiphyseal plates.

Question 7

List reasons why children tolerate exercise in heat more poorly than adults (3)

Answer 7

1. Children sweat less due to low rate of sweat production.
2. Reliance on convective heat loss from increased cutaneous blood flow.
3. General anthropometric and functional difference of immature thermo system.

Question 8

Children at high risk for heat-related illness include (4):

Answer 8

1. Disease affecting sweating mechanism; DM and cystic fibrosis.
2. Diseases affecting CV-system; congenital or DM.
3. Children w. obesity.
4. Children w. history of heat stroke.

Question 9

Maximal HR decreases approx. ___bpm per decade with age?

Answer 9

6-10bpm

Question 10

Probable reasoning for decreased maximal Q with advancing age?

Answer 10

Increased stiffness of LV, causing decreased diastolic filling.

Question 11

List other cardiovascular changes with advancing age (3):

Answer 11

1. Decreased arterial compliance, increased arterial stiffness.
2. Decreased skeletal muscle capillary density; decreased O2 extraction.
3. LV hypertrophy due to increased after-load.

Question 12

List three changes in Pulmonary Func w. age:

Answer 12

1. Residual volume increases, vital capacity decreases.
2. Lung compliance increases; loss of elastin fibers/ recoil.
3. Twenty percent increase in respiratory muscle work.

Question 13

What fibers are most likely susceptible to atrophy with advancing age?

Answer 13

Fast-twitch (esp. IIB).

Question 14

Why does the process of bone remodeling become unbalance with age?

Answer 14

Re-absorption from osteoblasts succeed’s bone formation from osteoclasts. Can lead to osteoporosis if process accelerates.

Question 15

Briefly list the Sex-Related difference in Bone Loss (2):

Answer 15

1. Bone loss in women (30-35 yrs) generally accelerates following menopause.
2. Bone loss men between 50-55 years

Question 16

With advancing age, joint stiffness and inflexibility results in ____?

Answer 16

1. Connective tissue less extensible: decreased tensile strength, increased stiffness.
2. Degeneration of joints; scar tissue formation leads to decreased response to stress.

Question 17

Age-related changes in which systems (3) result in diminished feedback to ______?

Answer 17

Systems affected: vestibular, visual, and somatosensory; affects postural centers.

Question 18

Reduced gait speed results in ____ with concomitant effects of (3):

Answer 18

decreased stride length; resulting in reduced arm swing, rotation of joints, increased double support time.

Question 19

List effects (3) of advancing age on Body Composition?

Answer 19

1. Gradual decrease in BMR.
2. Central fat mass.
3. Steady decline fat-free mass >45.

Question 20

A loss in circulating growth hormone with advancing age results in?

Answer 20

A loss of muscle mass and strength.

Question 21

What is mainly responsible for the increased risk of heart disease and osteoporosis that affects women.

Answer 21

Peri-and-post-menopausal where decreases in circulating levels of estrogen and progesterone occur.

Question 22

When strength training children/adolescents, what should the main focus of the training programme?

Answer 22

Participation and proper technique opposed to the amount of resistance.

Question 23

What type of activity has the greatest effect for enhancing bone mass?

Answer 23

Weight-lifting or compressive exercises.

Question 24

List the risk factors of orthopaedic/overuse injuries, and briefly give an exmaple for each

Answer 24

1. Training error (increased total volume).
2. Muscle-tendon imbalance (aysmetric stress on bones/joints).
3. Anatomic malalignments (discrepancies in leg length).
4. High-impact during running/jumping
5. Growth (susceptible to repetitive trauma)

Question 25

Deleterious effects for young female athletes who experience amenorrhea/menarche include:

Answer 25

Increased risk skeletal fragility and osteoporosis later in life.

Question 26

What are some strategies during exercise to reduce onset of exercise-induced asthma in children/adol?

Answer 26

Prolonged warm-up.

Question 27

List the four cardiovascular responses following exercise in children:

Answer 27

1. Lower cardiac output.
2. Submaximal HR is higher; due to heart size and SV.
3. MHR is higher.
4. Arterial BP is lower at submax and maximal workloads.

Question 28

List pulmonary responses following exercise in children:

Answer 28

1. Maximal minute ventilation is lower.

2. Higher breathing frequency.

Question 29

What is the minimum maximal O2 consumption value considered necessary for independent living?

Answer 29

VO2 max 13 ml/kg/min