Muscles of the Forearm and Hand: Muscles and Corresponding Actions
Abductor Digiti Minimi
Action: Abducts the little finger. A suprisingly powerful muscle, which particularly comes into play when fingers are spread to grasp a large object. Sports: Rock-face climbing, basketball, netball
Abductor pollicis brevis
Action: Abducts thumb and moves it anteriorly (as in typing or playing the piano). Assists in opposition of thumb Sports: Rock climbing
Palmar Interossei and Dorsal Interossei
Action: Adduct (converge) fingers and thumb towards the middle (third) finger (palmar interossei). Abduct fingers away from middle finger (dorsal interossei). Assist in flexion of fingers at metacarpophalangeal joints. Sports: Rock-face climbing
Adductor Pollicis
Action: Adducts the thumb Sports: Rock climbing
Lumbricales
Action: Extend the interphalangeal joints and simultaneously flex the metacapophalangeal joints of the fingers. Sports: Volleyball, handball
Finger extensors (Extensor digitorum)
Action: Extends the fingers. Assists abduction (divergence) of fingers away from the middle finger
Wrist flexor: Palmaris longus
Action: Flex the wrist Strengthening exercises: Biceps curl, wrist rolling (palm up), wrist curl Sports: Sailing, water skiing, golf, baseball, cricket, volleyball
Wrist flexor: Flexor carpi radialis
Action: Flex the wrist, abduct the wrist Strengthening exercises: Biceps curl, wrist rolling (palm up), wrist curl Sports: Sailing, water skiing, golf, baseball, cricket, volleyball
Wrist flexor: Flexor carpi ulnaris
Action: Flex the wrist, adduct the wrist Strengthening exercises: Biceps curl, wrist rolling (palm up), wrist curl Sports: Sailing, water skiing, golf, baseball, cricket, volleyball
Brachioradialis
Action: Flexes elbow joint. Assists in pronating and supinating forearm when these movements are resisited Strengthening exercises: Biceps curl, chin-ups, upright rowing Sports: Baseball, cricket, golf, racket sports, rowing
Flexor Pollicis Brevis
Action: Flexes the metacapophalangeal and carpometacarpal joints of the thumb. Assists in opposition of the thumb towards the little finger. Strengthening exercises: pinching Sports: Rock-face climbing. Motorcycle sports (clutch and throttle movement)
Opponens Digiti Minimi and Flexor Digiti Minimi Brevis
Action: Opponens digiti minimi: Pulls metacarpal of the little finger forward and rotates it laterally, so deepening the hollow of the hand, and enabling the pad of the little finger to contact the pad of the thumb. Flexor digiti minimi breviw: Flexes the little finger at the metacarpophalangeal joint Sports: Volleyball, handball, rock climbing
Opponens Pollicis
Action: Opposes (i.e. abducts, then slightly medially rotates, followed by flexion and adduction) the thumb so that the pad of the thumb can be drawn into contact with the pads of the fingers Strengthening exercises: pinching Sports: Rock-face climbing. Motorcycle sports (clutch and throttle movement)
Supinator
Action: Supinates forearn Strengthening exercises: dumb-bell biceps curl Sports: Backhand in racket sports
Pronator teres
Action: pronates forearm. Assists flexion of elbow joint. Strengthening exercises: pronation with strength bar Sports: Batting in cricket, hockey dribbling, volleyball spike
Wrist extensors
Extensor carpi radialis longus Extensor carpi ulnaris Extensor carpi radialis brevis Action: Extends wrist (extensor carpi radialis longus and brevis also abduct the wrist; extensor carpi ulnaris also adducts the wrist) Strengthening exercises: Wrist roller (palm down), reverse wrist curl, most dumb-bell exercises Sports: Back hand in racket sports, golf, motorcycle sports (throttle control)
Finger flexors
Flexor digitorum superficialis; Flexor pollicis longus; Flexor digitorum profundus Action: Superficialis: Flexes the middle phalanges of each finger. Can help flex the wrist; Profundus: Flexes distal phalanges (the only muscle able to do so) Strengthening exercises: Biceps curl, chin-ups, grip strength hand exerciser Sports: Archery, racket and batting sports, judo, rowing, rock-face climbing
