Draft version for length chart

This is a draft version for the muscle length chart.  The information will not be maintained in accuracy will not be further corrected by proofreading and is not or up to date.  It has too many words.  This is simply the notes used to construct a better version.

To see the shorter more accurate, better written, more up to date version go here

https://postscarcityfitness.blogspot.com/2022/08/muscle-length-chart.html

Disclaimer : This information is not guaranteed to be accurate and I am not liable if you make any decisions or take any actions, in terms of medical treatment, health decisions, exercise, behavior or anything else based on the information presented.  I am not telling you any decisions to make even if I use terms like "you" but am using the word "you" as part of a writing style to simplify writing.  Any suggestions for what "you" should do are not for you personally to do but what someone might do as part of a exercise or nutrition program which might help some people's health and make other people's health worse.  You should not do any activity that will make your health worse even if "you" should do it according to the program described.  If the information is wrong and you believe it is true, act on it and it causes you problems, I am not responsible because I have warned you the information is not guaranteed to be accurate.

This list primarily focuses on multiple joint voluntary skeletal muscles in the toe, foot, ankle, leg, knee, hip, finger, hand, wrist, forearm,, elbow and shoulder joints as well as what action is necessary to achieve stretching, active insuffiency and passive insuffiency for each muscle.  

By the forearm as a joint, I mean the radioulnar pivot joint that pronates and supinates.  By the leg as a joint that is related to a controversy about if the tibia and fibula really pronate and supinate as a pivot joint during foot medial and lateral rotation in the transverse plane or if the terms pronation and supination should be abandoned in regard to the leg, foot, or ankle as described here

http://postscarcityfitness.blogspot.com/2022/07/pronation-and-supination-of-tibia-and.html

I will try to include a list of every multiple joint voluntary skeletal muscle that attaches to the femur and every bone distal to the femur as well as the humerus and every bone distal to the humerus

This list may also include single joint muscles if specific exercises are necessary to achieve active or passive insuffiency in a single joint muscle that would not already be covered by an exercise for a multiple joint muscle or to mention redundancy with exercises for multiple joint muscles and why a special exercises is not needed to be included in this list for a single joint muscle

Even though this list may include some single joint muscles the primary focus is intended to be on multiple joint muscles because multiple joint muscles are the limiting factor for strength and range of motion at active and passive insufficiency or the limiting factor for flexibility more often then single joint muscles.  For example if a multiple joint muscle both flexes the knee and extends the hip it makes more sense to target it than a single joint muscle that flexes the knee only for flexibility if you can achieve a straight fully extended knee with the hip in at least one position if your goal is to increase flexibility.  For another example if a multiple joint muscle both extends the knee and flexes the hip it makes more sense to target it than a single joint muscle that extends the knee only for flexibility if you can achieve a fully flexed knee with the hip in at least one position if your goal is to increase flexibility.

The posture for stretching a muscle is sometimes the same as the posture for achieving passive insuffiency except the direction and magnitude of external force or external torque does not matter but only the length of the muscle for determining whether or not the muscle is stretching.  When a muscle is at active insuffiency it is not being stretched in the sense of being lengthened but sometimes a opposing muscle group is being stretched.  Strength training at active insuffiency can increase flexibility even though the muscle in active insuffiency is not being stretched because it increases the range of motion a joint can go through when resisting a certain amount of torque in a certain direction.

The goal of this list is to be able to achieve stretching, active insuffiency and passive insuffiency for each muscle on the list in as few postures, exercises or positions as possible. 

Each muscle will have a listed posture or set of postures for it's shortest position or positions which is used for achieving active insuffiency and a posture or posture for it's longest position or positions which are used for passive insuffiency or for stretching

It's shortest position or positions will be when it is engaged in the combination of action or actions it is listed as performing on a muscle chart and it's longest position or positions when it is stretched in the opposite direction of the actions it performs according to a muscle chart.

The muscles of the torso, face, head, neck and spine will not be included unless they effect the hip or shoulder joints listed because it will greatly increase the difficulty of comprehension.  And the number of listed exercises will already be immense as is. 

There are 6 rotations for  spinal muscle stretching sagital plane forward bending or forward flexion, sagital plane backward bending or backward extension, two directions of coronal plane side bending or lateral flexion and two directions of  transverse plane twisting for spinal exercises.  Additionally the spine can be translated to lengthen or shorten the distance between vertebra in response to forces of tension or compression, which is related to the claim that people's height increases while they sleep and decreases while they are awake and walking, sitting and standing throughout the day.  But knowing this is not enough because the spine has multiple vertebra and at many of these vertebra any of those six rotations can occur instead of only at one single joint.  The sternum is a bone in the middle of the torso that greatly restricts movement of the spinal joints and too a lesser extent the ribcage might also restrict movement of the spinal joints.  A good spinal muscle stretching program will pay special attention to the following four locations the bottom of the head where it intersects the top of the neck, the top of the sternum, the bottom of the sternum and the top of the pelvis.  Any good exercise system for stretching and strengthening the muscles that connect to the spine must take into account the 6 rotations and those four locations.  However such an exercise program is beyond the scope of this article because of the large number of spinal joints and the relationship between breathing and skeletal muscles and the many non skeletal muscle organs located in the trunk, making the intended task overwhelmingly complicated to do for skeletal muscles in the torso that do not effect the hip or shoulder joints directly.

Explanation of lateral flexion vs lateral extension

http://web.archive.org/web/20180708062300/http://vlb.fitnesslearningsystems.com/minicourses/kinesiology_mini/035_lat.htm

Making a list of joints lists of muscles that effect other joints do not cross to minimize the number of exercises necessary

I will make notes of what types of joints and movements should not effect active or passive insuffiency for a muscle.  For example none of the muscles for the joints of the toes have muscles that cross the hip joint so you theoritically do not have to worry about combinations of hip joint positions when exercising the toe joint muscles or toe joint positions when exercising hip joint muscles.  This methodology is important because it greatly reduces the number of combinations of positions for exercises.

What about joints muscles do not cross that effect force produced on external objects when exercising a muscle or joint range of motion

Making this list point out what joints do not determine if a muscle is being exercised based on what is distal or proximal to a muscle's point of attachment might not be completely accurate.   If for example two different muscles both have tendons that attach to the same sheet or segment of connective tissue or to the same bone.  Then, one may thus think the position of one joint does not effect whether or not a certain muscle is in active or passive insuffiency when indeed it does because two different muscles are both pulling on the same connective tissue or bone and each must exert extra force for the other to not move that connective tissue or bone to another position.  Even though I am aware of this possibility it shall be ignored on the list and pretended as though it is not true because otherwise the number of combinations might be multiplied by 8 for every extra joint included since 2 sagital plane directions of maximum rotation * 2 coronal plane directions of maximum rotation * 2 transverse plane directions of maximum rotation = 8 combinations or 27 combinations if a halfway neutral point between each of the opposite maximum directions of rotation are cinsidered.  I shall also ignore this possibility for another reason.  If a muscle is at it's shortest or longest length and exerts the maximum force it is capable of at that length then it is at active or passive insuffiency even if moving another joint that the muscle does not cross would enable it to produce more or less force on a object outside the body.  Therefore if the goal is to exercise each muscle at active or passive insuffiency in as low a number of different exercises as possible it is not necessary to add a extra exercise if a joint it does not cross increases or decreases the amount of force that can be applied to an object outside the human body.  Instead of adding an extra exercise to make up for the position of the joint that is not crossed by the muscle someone can simply adjust the amount of force applied to an object outside the body in response to this extra joint's position while maintaining the same exercise position in regards to the positions of the joints the muscle actually does cross.  If changing the position of this extra joint the muscle does not cross effects the sum of the maximum range of motion in all the joints this muscle does cross then this extra joint the muscle does not cross should be positioned so as not to decrease the maximum total range of motion of all joints the muscle does cross.

Determining Finger Exercises for active and passive insuffiency

With the exception of the thumb each of the fingers can primarily only actively move in four ways, abduction, adduction, flexion and extension at the Metacarpophalangeal or MCP joints, they can however move six ways including rotation in terms of passive flexibility in which they experience external force

Duplicate section of text except small word changes for fingers and toes

Since the intrinsic muscles do not cross the wrist or farther it is important to look at the extrinsic muscles.  Once all the extrinsic muscles are listed the remaining intrinsic muscles are known to theoritically not be influenced by the position of the wrist joint or any joint proximal to the wrist joint and that is important in limiting the number of exercises on this list.

Certain muscles act on a group of fingers and other muscles only act on individual fingers, it is important to look at the muscles that target individual fingers specifically even if they are intrinsic muscles if no extrinsic muscle exists that can target that specific finger joint with the specific type of action that intrinsic muscle does as opposed to only targeting a group of fingers

End of almost duplicate section

Extrinsic extensor muscles

The extrinsic extensor muscles of the hand have origins in either the ulna, radius, interosseous membrane of the forearm between the ulna and radius or the lateral supracondylar ridge, or common extensor tendon according to wikipedia.  This means the position of the shoulder or any joint proximal to the shoulder does not theoretically determine the muscle length of the extrinsic extensor muscles of the hand.  

The length of extrinsic extensor muscles that do attach to the supracondylar ridge of the humerus or the common extensor tendon could be effected by if the elbow is flexed or extended and additionally if the forearm or radioulnar joint is pronated or supinated.  

The length of extrinsic extensor muscles that do not attach to the supracondylar ridge of the humerus nor the common extensor tendon should not theoretically be effected by if the elbow is flexed or extended but maybe effected by if the forearm or radioulnar joint is pronated or supinated.  

Covert Extrinsic Muscles - The lumbricals are listed as an intrinsic muscle but they connect to another muscle the flexor digitorum profundus which connects to bone outside the hand instead of connecting to bone inside the hand

Other extrinsic finger and hand muscles - Called long flexors

Specific extrinsic muscles

Flexor digitorum profundus shortest - Wrist PIP, DIP and MCP are flexed.  

Flexor digitorum profundus longest - Wrist PIP, DIP and MCP are extended.

Flexor digitorum profundus length other factors - Pronation and Supination of forearm might effect muscle length.  Flexion or extension of elbow should not theoretically effect muscle length. Position of joints proximal to elbow should not theoretically effect muscle length.

Flexor pollicis longus shortest - Wrist is flexed, thumb IP and MP is flexed

Flexor Pollicis longus longest - Wrist is extended, thumb IP and MP are extended

Flexor Pollicis longus length other factors - Thumb CMC joint position, pronation or supination of the forearm might effect flexor pollicis longus muscle length.   Depending on anatomical variations of the muscles point of origin, flexion or extension of the elbow might effect flexor pollicis longus muscle length.  Position of shoulder joint and joints proximal to the shoulder theoretically should not effect flexor pollicis longus muscle length

Specific Intrinsic muscles

Lumbricals Shortest - Shortest when MCP is flexed and both PIP and DIP extended for four non thumb fingers

Lumbricals Longest - Longest when MCP is extended and both PIP and DIP flexed for four non thumb fingers

Lumbricals length other factors - Even though the Lumbricals are allegedly intrinsic they might be shortest when the wrist is flexed and longest when the wrist is extended because they attach to the tendons of the flexor digitorum profondous.  Muscle length might be effected by pronation or supination of forearm due to attachment to flexor digitorum profondous.  Muscle length should not theoretically be effected by flexion or extension of the elbow joint or by the position of any joint proximal to the elbow joint.

Muscles that insert into the hand and flex, extend, adduct or abduct the wrist but do not move the finger or thumb joints

Muscles that insert into the forearm and do not move the thumb or finger joints and also do not flex, extend, abduct or adduct the wrist

Pronator Quadratus shortest - forearm is pronated

Pronator Quadratus longest - forearm is supinated

Pronator Quadratus muscle length  other factors - This muscle does not cross the wrist or elbow joint and so the position of the wrist or joints distal to the wrist and flexion or extension of the elbow or joints proximal to the elbow should not effect pronator quadratus length

Pronator Teres shortest - Elbow is flexed and forearm is pronated

Pronator Teres longest - Elbow is extended and forearm is supinated

Pronator Teres muscle length other factors - This muscle does not cross the wrist or shoulder joint and so the position of the wrist or joints distal to the wrist and the shoulder and joints proximal to the shoulder should not effect pronator teres length

Muscles that insert into the humerus and do not move the joints distal to the humerus

References

The three joints are as follows:

Carpometacarpal (CMC) Joint

Metacarpophalangeal (MP) Joint

Interphalangeal (IP) Joint

https://web.archive.org/web/20210729055004/https://noelhenley.com/280/joints-of-the-thumb/

Flexor digitorum profundus is a flexor of the wrist (midcarpal), metacarpophalangeal and interphalangeal joints.[1] The lumbricals, intrinsic muscles of the hand, attach to the tendon of flexor digitorum profundus.

https://web.archive.org/web/20220703014856/https://en.wikipedia.org/wiki/Flexor_digitorum_profundus_muscle

Flexor digitorum profundus originates in the upper 3/4 of the anterior and medial surfaces of the ulna, interosseous membrane and deep fascia of the forearm. 

https://web.archive.org/web/20220703014856/https://en.wikipedia.org/wiki/Flexor_digitorum_profundus_muscle

The lumbrical muscles, with the help of the interosseous muscles, simultaneously flex the metacarpophalangeal joints while extending both interphalangeal joints of the digit on which it inserts. The lumbricals are used during an upstroke in writing.

https://web.archive.org/web/20220620024654/https://en.wikipedia.org/wiki/Lumbricals_of_the_hand

The lumbricals are four, small, worm-like muscles on each hand. These muscles are unusual in that they do not attach to bone. Instead, they attach proximally to the tendons of flexor digitorum profundus,[1][2][3] and distally to the extensor expansions.[1][3] The first and second lumbricals are unipennate, while the third and fourth lumbricals are bipennate

https://web.archive.org/web/20220620024654/https://en.wikipedia.org/wiki/Lumbricals_of_the_hand

An extensor expansion (extensor hood,[1] dorsal expansion, dorsal hood, dorsal aponeurosis[citation needed]) is the special connective attachments by which the extensor tendons insert into the phalanges.

https://web.archive.org/web/20220703014856/https://en.wikipedia.org/wiki/Extensor_expansion

Structure

The common extensor tendon serves as the upper attachment (in part) for the superficial muscles that are located on the posterior aspect of the forearm:

Extensor carpi radialis brevis

Extensor carpi radialis longus <----- This attaches to the supracondylar ridge, not the common extensor tendon

Extensor digitorum

Extensor digiti minimi

Extensor carpi ulnaris[1][2]

The tendon of extensor carpi radialis brevis is usually the most major tendon to which the other tendons merge.[2]

Function

The common extensor tendon is the major attachment point for extensor muscles of the forearm. This enables finger extension and aids in forearm supination.

https://web.archive.org/web/20220703014850/https://en.wikipedia.org/wiki/Common_extensor_tendon

The common extensor tendon is a tendon that attaches to the lateral epicondyle of the humerus.

https://web.archive.org/web/20220703014850/https://en.wikipedia.org/wiki/Common_extensor_tendon

The lateral supracondylar ridge is a prominent, rough margin on the lower part of the lateral border of the humerus. It presents an anterior lip for the origin of forearm extensors, including the brachioradialis muscle above, and the extensor carpi radialis longus muscle below.[1] It also presents a posterior lip for the triceps brachii, and an intermediate ridge for the attachment of the lateral intermuscular septum.

https://web.archive.org/web/20220418090025/https://en.wikipedia.org/wiki/Lateral_supracondylar_ridge

The interosseous membrane of the forearm (rarely middle or intermediate radioulnar joint) is a fibrous sheet that connects the interosseous margins of the radius and the ulna.

https://web.archive.org/web/20161205122447/https://en.wikipedia.org/wiki/Interosseous_membrane_of_forearm

The extrinsic extensor muscles of the hand are located in the back of the forearm and have long tendons connecting them to bones in the hand, where they exert their action. Extrinsic denotes their location outside the hand. Extensor denotes their action which is to extend, or open flat, joints in the hand. They include the extensor carpi radialis longus (ECRL), extensor carpi radialis brevis (ECRB), extensor digitorum (ED), extensor digiti minimi (EDM), extensor carpi ulnaris (ECU), abductor pollicis longus (APL), extensor pollicis brevis (EPB), extensor pollicis longus (EPL), and extensor indicis (EI).

https://web.archive.org/web/20220324081521/https://en.wikipedia.org/wiki/Extrinsic_extensor_muscles_of_the_hand

The extrinsic muscles of the hand are muscles that originate outside the hand but insert into structures within the hand 1,2. Most of the extrinsic muscles have their origins within the forearm, with several solely/also originating from the humerus:

flexor carpi radialis muscle

palmaris longus muscle

flexor carpi ulnaris muscle

flexor digitorum superficialis muscle

flexor digitorum profundus muscle

flexor pollicis longus muscle

pronator quadratus muscle

extensor carpi radialis longus muscle

extensor carpi radialis brevis muscle

extensor digitorum muscle

extensor digiti minimi muscle

extensor carpi ulnaris muscle

abductor pollicis longus muscle

extensor pollicis longus muscle

extensor pollicis brevis muscle

extensor indicis muscle

https://web.archive.org/web/20210526143409/https://radiopaedia.org/articles/extrinsic-muscles-of-the-hand

In 40 percent of cases, it is also inserted from the medial epicondyle of the humerus

https://web.archive.org/web/20220529171612/https://en.wikipedia.org/wiki/Flexor_pollicis_longus_muscle

The flexor pollicis longus is a flexor of the phalanges of the thumb; when the thumb is fixed, it assists in flexing the wrist.

https://web.archive.org/web/20220529171612/https://en.wikipedia.org/wiki/Flexor_pollicis_longus_muscle

It is the only muscle that attaches only to the ulna at one end and the radius at the other end.

https://web.archive.org/web/20201112012116/https://en.wikipedia.org/wiki/Pronator_quadratus_muscle

Together the flexor pollicis longus, pronator quadratus, and flexor digitorum profundus form the deep layer of ventral forearm muscles.

https://web.archive.org/web/20220703014856/https://en.wikipedia.org/wiki/Flexor_digitorum_profundus_muscle

Pronator teres pronates the forearm, turning the hand posteriorly. If the elbow is flexed to a right angle, then pronator teres will turn the hand so that the palm faces inferiorly. It is assisted in this action by pronator quadratus.

It also weakly flexes the elbow, or assists in flexion at the elbow when there is strong resistance.

https://web.archive.org/web/20200928004138/https://en.wikipedia.org/wiki/Pronator_teres_muscle

Compartment 1 (Most radial)	Compartment 2	Compartment 3	Compartment 4	Compartment 5	Compartment 6 (Most ulnar)
Abductor pollicis longus	Extensor carpi radialis longus	Extensor pollicis longus	Extensor indicis	Extensor digiti minimi	Extensor carpi ulnaris
Extensor pollicis brevis	Extensor carpi radialis brevis		Extensor digitorum communis

https://web.archive.org/web/20220506070323/https://en.wikipedia.org/wiki/Muscles_of_the_hand#Extrinsic

The muscles of the hand can be subdivided into two groups: the extrinsic and intrinsic muscle groups. The extrinsic muscle groups are the long flexors and extensors. They are called extrinsic because the muscle belly is located on the forearm. The intrinsic group are the smaller muscles located within the hand itself. 

http://web.archive.org/web/20201111180550/https://en.m.wikipedia.org/wiki/Muscles_of_the_hand

The metacarpophalangeal joints (MCP) are a collection of condyloid joints that connect the metacarpus, or palm of the hand, to the fingers

http://web.archive.org/web/20200809054331/kenhub.com/en/library/anatomy/metacarpophalangeal-mcp-joints

The primary movements of the metacarpophalangeal joints are flexion, extension, abduction, adduction, circumduction and limited rotation

http://web.archive.org/web/20200809054331/kenhub.com/en/library/anatomy/metacarpophalangeal-mcp-joints

Axial rotation is most important for the MCP joint of the thumb and it occurs during opposition. The rotation can be active or passive. The active axial rotation produced by simultaneous action of flexor pollicis brevis and abductor pollicis brevis muscles. Active rotation is always directed medially, while the passive movement can be directed in either direction.

http://web.archive.org/web/20200809054331/kenhub.com/en/library/anatomy/metacarpophalangeal-mcp-joints

A condyloid joint (also called condylar, ellipsoidal, or bicondylar[1]) is an ovoid articular surface, or condyle that is received into an elliptical cavity. This permits movement in two planes, allowing flexion, extension, adduction, abduction, and circumduction.

http://web.archive.org/web/20210421214839/https://en.m.wikipedia.org/wiki/Condyloid_joint

Determining Toe Exercises for active and passive insuffiency

Duplicate section of text except small word changes for fingers and toes

Since the intrinsic muscles do not cross the ankle or farther it is important to look at the extrinsic muscles.  Once all the extrinsic muscles are listed the remaining intrinsic muscles are known to theoritically not be influenced by the position of the ankle joint or any joint proximal to the ankle joint and that is important in limiting the number of exercises on this list.

Certain muscles act on a group of toes and other muscles only act on individual toes, it is important to look at the muscles that target individual toes specifically even if they are intrinsic muscles if no extrinsic muscle exists that can target that specific toe joint with the specific type of action that intrinsic muscle does as opposed to only targeting a group of toes

End of almost duplicate section

References

When we discuss the muscles of the foot, they are often separated into two groups – intrinsic and extrinsic muscles. Intrinsic means the muscles originate and insert in the foot, while extrinsic means the muscle starts outside the foot (eg somewhere along the shin) but inserts in the foot (think along the lines of your calf muscles).

http://web.archive.org/web/20210805072643/barefootphysiotherapy.com.au/intrinsic-foot-muscles/

https://duckduckgo.com/?q=intrinsic+muscles+of+the+foot&ia=web

All four lumbricals insert into extensor hoods of the phalanges, thus creating extension at the inter-phalangeal (PIP and DIP) joints. However as the tendons also pass inferior to the metatarsal phalangeal (MTP) joints it creates flexion at this joint.

https://web.archive.org/web/20141206132955/https://en.wikipedia.org/wiki/Lumbrical_muscle_of_the_foot

More references

http://web.archive.org/web/*/kenhub.com/en/library/anatomy/arthrology

http://web.archive.org/web/*/https://www.kenhub.com/en/library/anatomy/types-of-movements-in-the-human-body

Copyright Carl Janssen 2022