Mr. DeMarco
Room 123
MUSCULAR SYSTEM - DAY 2
What's the "busiest" muscle in the human body?
Mr. DeMarco
Room 123
MUSCULAR SYSTEM - DAY 2
What's the "busiest" muscle in the human body?
OBJECTIVES
MUSCULAR SYSTEM - DAY 2
DO YOU KNOW YOUR
SKELETAL MUSCLES
MASSETER
STERNOCLIEDOMASTOID
PECTORALIS MAJOR
PEC MINOR & SERRATUS
RECTUS, OBLIQUES, TRANSVERSE
TRAPEZIUS
LATISSIMUS DORSI
RHOMBOIDS & ERECTOR SPINAE
QUADRATUS LUMBORUM
masseter
DELTOIDS
BICEPS BRACHII
TRICEPS BRACHII
BRACHIORADIALIS
HIP FLEXORS
QUADRICEPS (FEMORIS)
HAMSTRINGS
HIP ADDUCTORS
TIBIALIS ANTERIOR
PERONEALS
MUSCLE CELLS
have the ability to shorten (contract) and move the skeleton
muscle cells can only actively contract, they can't actively lengthen
HOW DO MUSCLES LENGTHEN
ANTAGONIST
MUSCLES
are often arranged in agonist and antagonist pairs to enable opposing actions
AGONIST
muscle that contracts or shortens to create a specific movement
ANTAGONIST
muscle that lenghtens or relaxes to create a specific movement
for any given movement...
MUSCLE CONTRACTS MUSCLE LENGTHENS
for any given movement...
MUSCLE GETS SHORTER MUSCLE GETS LONGER
THE MUSCLE GETTING SHORTER IS CAUSING THE MOVEMENT
MAP"MAJOR" MOVEABLEJOINTS
a muscle must cross a joint in order to act upon it
*NOW* SEGMENTATION
The hip flexor muscles (iliopsoas, rectus femoris sartorius, and pectineus) flex the hip. What muscle(s) flex the knee? Elbow? Shoulder?
IRON DEN
EXPECTATIONS
BEHAVIORALLY
MUSCULAR - DAY 2
Anthony DeMarco
Created on April 13, 2026
Start designing with a free template
Discover more than 1500 professional designs like these:
View
Essential Business Proposal
View
Project Roadmap Timeline
View
Step-by-Step Timeline: How to Develop an Idea
View
Artificial Intelligence History Timeline
View
Mobile Phone Call
View
Momentum: Tools Tutorial
View
Momentum: Onboarding Video
Explore all templates
Transcript
Mr. DeMarco
Room 123
MUSCULAR SYSTEM - DAY 2
What's the "busiest" muscle in the human body?
Mr. DeMarco
Room 123
MUSCULAR SYSTEM - DAY 2
What's the "busiest" muscle in the human body?
OBJECTIVES
MUSCULAR SYSTEM - DAY 2
DO YOU KNOW YOUR
SKELETAL MUSCLES
MASSETER
STERNOCLIEDOMASTOID
PECTORALIS MAJOR
PEC MINOR & SERRATUS
RECTUS, OBLIQUES, TRANSVERSE
TRAPEZIUS
LATISSIMUS DORSI
RHOMBOIDS & ERECTOR SPINAE
QUADRATUS LUMBORUM
masseter
DELTOIDS
BICEPS BRACHII
TRICEPS BRACHII
BRACHIORADIALIS
HIP FLEXORS
QUADRICEPS (FEMORIS)
HAMSTRINGS
HIP ADDUCTORS
TIBIALIS ANTERIOR
PERONEALS
MUSCLE CELLS
have the ability to shorten (contract) and move the skeleton
muscle cells can only actively contract, they can't actively lengthen
HOW DO MUSCLES LENGTHEN
ANTAGONIST
MUSCLES
are often arranged in agonist and antagonist pairs to enable opposing actions
AGONIST
muscle that contracts or shortens to create a specific movement
ANTAGONIST
muscle that lenghtens or relaxes to create a specific movement
for any given movement...
MUSCLE CONTRACTS MUSCLE LENGTHENS
for any given movement...
MUSCLE GETS SHORTER MUSCLE GETS LONGER
THE MUSCLE GETTING SHORTER IS CAUSING THE MOVEMENT
MAP"MAJOR" MOVEABLEJOINTS
a muscle must cross a joint in order to act upon it
*NOW* SEGMENTATION
The hip flexor muscles (iliopsoas, rectus femoris sartorius, and pectineus) flex the hip. What muscle(s) flex the knee? Elbow? Shoulder?
IRON DEN
EXPECTATIONS
BEHAVIORALLY