The document discusses muscle physiology concepts including: 1) The all-or-none law which states that a muscle fiber generates full force when stimulated or none at all. 2) Muscle fatigue and oxygen debt which occur when more oxygen is used than taken in, leading to a build up of lactic acid and lower pH levels. 3) The three types of muscle contraction - isometric, concentric, and eccentric - and examples of activities for each type. 4) The roles of agonists, antagonists, synergists, and fixators in muscle movements and how they work to create or oppose actions.

1. Lloyd Dean Muscle Contraction

2. Aims By the end of the lesson you should be able to: Describe the all or none law of muscle physiology. State muscle fatigue and oxygen debt in relation to muscle contraction List the types of muscle contraction Describe agonists, antagonist, synergists and fixators applied to a range of exercises.

3. All or None Law To fire a gun there must be enough force to pull the trigger If you pull the trigger harder the bullet does not travel faster! A contracted muscle receives a nerve impulse either completely or not at all The action potential (Nerve impulse) is at full strength or not at all This is the All or None Law!

4. Muscle Fatigue & Oxygen Debt How do these both impact the muscle contraction? If no ATP is available no contraction will take place If you use more oxygen that is taken in through the lungs then there is a deficit of oxygen This can make the blood PH level rise, and become acidic (Commonly know as an increase in Lactate acid) This is a by product of exercises without oxygen, or anaerobically

5. Antagonistic Pairs Biceps – Prime mover Triceps – Antagonistic This muscle determines the movement of an action –by Contracting Biceps – Antagonistic Triceps – Prime Mover This muscle works with the prime mover but creates an opposing action – by relaxing

6. Agonist, Antagonists and....... Synergists Fixators Help to steady the movement In biceps curl the brachialis helps the action Assist in stabilising the origin of the agonist to ensure movement occurs In biceps curl the fixators would

7. Muscle contraction Three types Isometric Concentric Eccentric

8. Isometric Contraction Muscle stays the same length during Contraction or when the activity is being carried out. Name a sport/activity where isometric contraction occurs?

9. Concentric Contraction This where the muscle shortens when performing an action Name a sport/activity where Concentric contraction occurs?

10. Eccentric Contraction Where the muscle lengthens under tension – ends of the muscle move further away during an action Name a sport/activity where Eccentric contraction occurs?

12. Muscle Tone Muscle tissue never really relaxes and is in constant partial contraction – this gives muscle its shape or tone.

13. Review of aims You should now be able to: Describe the all or none law of muscle physiology. State muscle fatigue and oxygen debt in relation to muscle contraction List the types of muscle contraction Describe agonists, antagonist, synergists and fixators applied to a range of exercises.