PHYSIOLOGY OF EXERCISE
MUSCLE TYPES
• Skeletal
• Heart
• Smooth
EXERCISE:
1. Dynamic (positive/negative)
2. Static
Agonist and antagonist act one against the other (e.g. flexion of
elbow - biceps brachialis - agonist, triceps brachialis - antagonist).
Antagonist is never
completely relaxed - control and
reduction of movement by
keeping the tonus against the
agonist (excentric movement)
Types of
contractions:
1. isometric
2. dynamic (isotonic)
a.
concentric
b. excentric
CHANGES DURING EXERCISE:
1. Cardiovascular
2. Respiratory
3. Metabolic
„Fight or flight“ – EVOLUTIONAL ASPECT
THERMOREGULATION
HOMEOSTASIS
ANTICIPATION OF WORK
CARDIOVASCULAR REACTIONS DURING WORK
1. Reactions of the heart
2. Reactions of the vessels
Demands on cardiovascular system:
1. Increase of cardiac output
2. Increase in coronary blood flow
3. Hyperaemia in lung circulation
4. Hyperaemia in muscles (difference between contraction and relaxation!!!)
5. Higher supply of O2 and metabolites, higher removal of CO2 and catabolites
Ergotropic system – sympathetic NS
REDISTRIBUTION OF BLOOD
METABOLIC REGULATION OF BLOOD FLOW
Decreased pH, decreased pO2, increased pCO2, increased K+, increased body temperature
CARDIAC RESERVE = maximal CO / resting CO
CORONARY RESERVE = maximal CF / resting CF
CHRONOTROPIC RESERVE = maximal HR / resting HR
VOLUME RESERVE = maximal SV / resting SV
4 - 7
3.5
3 - 5
1.5
CO – cardiac output, CF – coronary flow, HR – heart rate, SV – stroke volume
CARDIAC RESERVE
CO (l/min)
WORKLOAD (W/kg)
ATHLETHS HEART
PHYSIOLOGICAL RESPONSE
HEART FAILURE
1 2 3 4
10
30
20
PARAMETER REST EXERCISE INCREASE (x)
Cardiac output
(l/min)
5-6 25 (35) 4-5 (7)
Cardiac reserve
Heart rate
(t/min)
70 210 (250-190)
depends on age
3-5
Chronotropic reserve
Stroke volume
(ml)
75 115 1.5
Volume reserve
Systolic BP
(mmHg)
120 ? Diastolic
BP
(mmHg)
70 ? Pulse
BP
(mmHg)
50 70-100 1.5-2
Mean BP
(mmHg)
- - minor increase
Muscle perfusion
(ml/min/100g)
2-4 60-120 30
(10% MVmax)
RESPIRATORY REACTIONS DURING EXERCISE
Demands on respiratory system:
1. Higher gases exchange – higher diffusion
2. Higher ventilation
3. Higher perfusion (hyperaemia in lung circulation)
PARAMETER REST EXERCISE INCREASE (x)
Minute ventilation
(l/min)
6-12 90-120 15-20
Respiratory frequency
(d/min)
12-16 40-60 4-5
Tidal volume (ml) 0,5-0,75 2 3-4
Blood flow (l/min) 5,5 20 – 35 4-6
O2 intake (ml/min) -VO2 250-300 3000 10-12
Total CO2 (ml/min) 200 8000 40
pO2 (Torr) 40 25
O2 extraction (%) + + ++
Time
Ventilation
(l / min)
rest work recovery
hyperpnoe tachypnoe
Psychic
Proprioception
„Humoural“ stimulation
(K+, temperature, CO2, O2)
tachypnoe
(oxygen debt)
H+
a
R = 1.5 – 2.0 R = 0.5
Guyton and Hall: Textbook of Medical Physiology
D.U.Silverthorn: Human Physiology (An Integrated Approach)
D.U.Silverthorn: Human Physiology (An Integrated Approach)
D.U.Silverthorn: Human Physiology (An Integrated Approach)
D.U.Silverthorn: Human Physiology (An Integrated Approach)
D.U.Silverthorn: Human Physiology (An Integrated Approach)
D.U.Silverthorn: Human Physiology (An Integrated Approach)
Guyton and Hall: Textbook of Medical Physiology
FITNESS
• Spiroergometry
• Types of ergometers
• Index W170
• Training
• Fatigue (aerobic, anaerobic threshold)
• Adaptation to exercise