This section gives a simple explanation of the body including the skeleton and the muscle types.
The description of muscles types includes details on the type of energy they consume when being used.
The musculoskeletal system (The skeleton)
The human body is composed of a skeleton, which is a system of bones that is joined together.
The skeleton is the body's only rigid structure and performs three important functions:
(1) Supports the bodies structure
(2) Provides attachment for muscles which when they contract move the bones acting as a system of levers.
(3) Protection e.g. the ribs protect the heart and lungs.
Muscles and muscle fibre types
There are roughly 600 muscles in the human body, which are arranged in pairs in terms of the movement they produce.
For example the biceps flex while the triceps extend.
Muscles work by converting the chemical energy provided by food into movement energy and are made up of as mixture of 2 main fibre types.
(1) Fast twitch muscle fibres
(2) Slow twitch muscle fibres.
The fast twitch fibres can produce high-speed movement but only for a short period of time and produce a large amount of lactic acid. They have low fatigue resistance (you get tired quickly) and low energy efficiency (they consume a lot of energy when being used). Their primary fuel is carbohydrate.
Slow twitch fibres can operate for longer periods but contain less power. They have high fatigue resistance (you can maintain activity for longer) and high-energy efficiency (they don’t consume a lot of energy when being used).
They run on a mixture of fat and carbohydrate and are more effective at removing waste products and therefore can run for longer. |
|
|
