THE MUSCULAR SYSTEM By Alexis DiStasio and Kate Brown
Feb 23, 2016
THE MUSCULAR SYSTEMBy Alexis DiStasio and Kate Brown
- Large muscular system which allows movement
- Gives a horse definition- Allows posture
The Equine Muscular System
3 Types of Muscles Smooth
Cardiac
Skeletal
Smooth Muscle Found in digestive, circulatory, and
urogenital systems Sustained, rhythmic contractions Made up of spindle-shaped cells with a
single nucleus Least specialized Involuntary movement
Cardiac Muscle Found only in the heart Highly specialized Rapid, rhythmical contraction and
relaxation Never tires, allowing heart to continually
pump blood Involuntary movement
Skeletal Muscle Most highly specialized Used for movement and can contract
quickly Function: to provide powerful, rapid
contractions to allow locomotion Attached to limbs of skeleton Voluntary – controlled by brain and
nervous system
- Voluntary muscles are significant.
- Flexor muscles: - bend joint
- Extensor muscles: - straighten joints
Riding Horse
Rhomboideus This is a long triangular muscle located at the top of the neck Action - To draw the scapula upwards and
forwards
Splenius
A triangular muscle located on the side of the neck Action- Acting alone, the splenius draws
the head and neck towards the side
Trapezius Situated on the side of the neck and
withers. It is a triangular muscle Action - acting alone the trapezius pulls
the shoulder upwards and forwards.
Latissimus dorsi Located on along the back down to the
chest Acting alone helps move the front legs
and chest
Superficial Gluteus The most superficial muscle of the croup. It is V-shaped Action – move the thigh outward
Biceps femoris long, thick, muscle extending from the superior part of the
croup to the stifle Action- It flexes the tibia and with
assistance helps in the act of rearing
External Intercostal A series of thin, flat muscles between the
ribs Action - Move the ribs upward and
forward and assist in inspiration.
Posterior Deep Pectoral Broad flat muscle Extends from under the abdomen Action – to pull the scapula in a backward
direction
Branchiocephalicus Long, thick muscle located in the neck Action - help move the neck
Masseter Thick square muscle Located on the lower jaw Action – brings the teeth of the lower jaw
and the teeth of the upper jaw together
Slow-Twitch Muscle Fibres
Slow contractions and relaxation times Used for maintaining posture when exercising
at slow speeds Gain energy to function through aerobic
(oxygen) metabolism only Activities such as driving, dressage, and
endurance riding
Fast-Twitch Muscle Fibres Two Kinds:
Fast-twitch, high-oxidative fibers Fast-twitch, low-oxidative fibers
Fast-Twitch, High-Oxidative Fibres
Good oxygen capacity Use oxygen to supply energy while
working at high speeds Gain energy through aerobic and
anaerobic metabolism Used during eventing, jumping, polo, and
racing
Fast-twitch, Low-Oxidative Fibres
Does not have good oxygen capacity Burn oxygen quickly Used for short bursts of fast work Anaerobic metabolism only
Work Cited http://www.eec-equine-therapy.com/Muscular-System.html
http://www.irishhorsesociety.com/horsedata/muscles.htm http://chestofbooks.com/animals/horses/Health-Disease-Tr
eatment-2/Muscles-Of-The-Neck-Rhomboideus.html Anatomy and Physiology of Farm Animals. Pages 164-65 The Equine Body. By Beth Maloney (Chpt. 6)