Muscle contraction occurs when the protein filaments actin and myosin slide over one another, generating tension within muscle fibers. Muscle fatigue results from vigorous exercise and prevents the normal stages of muscle contraction from occurring. Fatigue is a feeling of tiredness that causes a need to rest due to a lack of energy or strength, which can be caused by overwork, poor sleep, worry, or lack of exercise.

1. WELCOME
PRESENTEDBY
THUSHARA T R

3. MUSCLE CONTRACTION
• Muscle contraction is the activation
of tension-generating sites within muscle
fibers In physiology, muscle contraction does
not mean muscle shortening because muscle
tension can be produced without changes in
muscle length such as holding a heavy book or
a dumbbell at the same position.

4. ACTIN AND MYOSIN

5. • Muscles are composed of two major protein
filaments: a thick filament composed of the
protein myosin and a thin filament composed
of the protein actin. Muscle contraction
occurs when these filaments slide over one
another in a series of repetitive events.

6. STEPS OF MUSCLE CONTRACTION

8. MUSCLE FATIGUE
• Muscle fatigue is the decline in ability of
a muscle to generate force. It can be a result
of vigorous exercise but abnormal fatigue may
be caused by barriers to or interference with
the different stages of muscle contraction.

9. REASON OF MUSCLE FATIGUE
• If muscle weakness is the result of pain, the
person may be able to make muscles work,
but it will hurt. Fatigue is a feeling
of tiredness or exhaustion or a need to rest
because of lack of energy or
strength. Fatigue may result from overwork,
poor sleep, worry, boredom, or lack of
exercise

10. MUSCLE FATIGUE

11. REVIEW QUESTIONS
• What is muscle contraction?
• What are the myofilaments?
• What is the role of calcium in muscle
contraction?
• what is muscle fatigue?

12. FOLLOW UP ACTIVITY
• Write a short note on muscle contraction.
• Draw the stages of muscle contraction in your
science diary?

13. THANKYOU