Page 9 - Lesson 5.xps

Physical and Physiological Aspects of Physical Education MODULE-2
Dimension of Physical
Education and Yog
DO YOU KNOW?

Skeletal muscles are composite of muscle fibres which can be divided in to
two categories: Type I is also known as slow-twitch fibres and Type II known
as fast-twitch. Our body has both categories of fibres; the composition may
change depending upon the training:
a) Type I (slow-twitch) fibres contracting slowly with less force, fatigue
comes slowly which suits for long duration aerobic activities eg. Long Note
distance races, Aerobics etc.
b) Type II (fast-twitch) fibres contract faster and produce great force but
fatigue comes faster; anaerobic activities suit this types of fibres eg. Short
distance races, 100 M, 200 M etc.

INTEXT QUESTIONS 5.1

1) Which type of muscle is under control of conscious functioning of nervous
system?

2) Fill in the blanks with appropriate words.

a) If you have 80% of ................................................................................
fibres in your muscles, then you can give good timings in sprint rather
than marathon.

b) When we do exercise biceps curl repetition then we do ...............
..............................................................................................................
muscle contraction.

c) In weightlifting, somebody is lifting the weight of 80% of his capacity
that is known as .....................................................................
d) Contraction is executed on consistent pace where muscle shortening is
maximum over full range of motion .........................................................

ACTIVITY 5.1

Prepare a chart of 10 Isometric exercises and 10 Isotonic exercises.
Hint: Search on Internet

5.2.1 Effects of Exercises on Muscular System
When we do exercise, our muscle system responds differently according to long
term or short term activity. These responses are known as acute responses caused
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