Transcript Physiology, Health & Exercise

Physiology, Health & Exercise
Lesson 9
The “Athletic” Heart
The “Athletic” Heart
 Cardiac hypertrophy
 Endurance training & LV
 Maximal heart rate & cardiac output
2
Athletes are fitter than most
people.
Why?
 Undergo regime of training
 Exercise at more extreme levels
 Exercise for longer periods of time
 Have shorter recovery times
 Lower HR at rest- 30-40 bpm
3
Athletes are fitter than most
people.
 Strengthened cardiac muscle- capable of
more forceful contraction- higher SV- even
at rest
 Athlete’s heart actually gets bigger- cardiac
hypertrophy
 Increase in protein synthesis in cardiac
muscle fibres  increase in contractile
elements within each fibre  increase in size
4
Athletes are fitter than most
people.
If you measure the size of cardiac muscle and
volumes of the heart chambers using
echocardiography and compare trained and
untrained people:
5
Left ventricular
mass (g)
Left ventricular
volume (ml)
Untrained
210
100
Trained
300
180
What 2 conclusions can you draw from this data?
6
In non-athletes increase in CO
is due to increase in HR
 Is this the same for athletes?
Max HR
(bpm)
Max SV
(ml)
Max CO
(l/min)
Untrained
170
120
20
Trained
195
180
35
Larger CO due to relatively greater increase
in SV in athletes
7
Athletes are fitter than most
people.
 Increase in size of heart in athletes is
temporary- if intensity of training decreases
then heart returns to pre-training size.
8
Questions
 2006 SQA Q1 in Physiol section to be
completed in class .
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