MUSCLE CONTRACTION YEAR 11 P.E

TYPES OF CONTRACTIONS… What are the different muscle contractions?

ISOTONIC – WHEN MUSCLE LENGTH CHANGES THROUGH A RANGE OF MOTION Concentric – Muscle shortening (upward phase in bicep curl) Eccentric – Muscle lengthening while tension is developed (lowering weight in bicep curl)

ISOMETRIC – VERY LITTLE CHANGE IN MUSCLE LENGTH WHILE TENSION IS DEVELOPED Example: Holding a weight stationary (in one place/still)

ISOKENETIC -Similar to isotonic (muscle changes length during the contraction) where they differ is that Isokinetic contractions produce movements of a constant speed. To measure this a special piece of equipment known as an Isokinetic Dynamometer is required. Examples of using isokinetic contractions in day-to-day and sporting activites are rare. The best is breast stroke in swimming, where the water provides a constant, even resistance to the movement of adduction.

Sliding Filament Theory: -method by which muscles are thought to contract. At a very basic level each muscle fibre is made up of smaller fibres called myofibrils. These contain even smaller structures called actin and myosin filaments. These filaments slide in and out between each other to form a muscle contractions, hence called the sliding filament theory!

Stretched/Extended Muscle: Partially contracted Muscle: Fully Contracted Muscle:

1. CREATE YOUR OWN MUSCLE CONTRACTION Research how to show muscle contraction in a visual way using your own bodies… 2. RESEARCH SLIDING FILAMENT THEORY Create a PP/Poster/Skit/Speech explaining how sliding filament theory works…

GLOSSARY OF TERMS Create a Glossary of important terms (key words) at the back of your book…