Lab 5 Procedures (156-183)

Question 1

What is exercise 1

Answer 1

Muscle activity (EMG) and Grip Strength

Question 2

What is the aim of exercise 1

Answer 2

To DETERMINE the RELATIONSHIP btwn EMG activity and GRIP STRENGTH in subject’s DOMINANT ARM

Question 3

Procedure for exercise 1 Muscle Activity (EMG) and Grip Strength

Answer 3

• Clean skin with alcohol
• • Place 3 electrodes on forearm of subject’s dominant arm. RED LEAD (+) attached to electrode near elbow, BLACK LEAD (-) attached to electrode in middle of forearm, GREEN LEAD (ground) attached to electrode on wrist

1. Subject sit quietly w/dominant forearm resting on table top
2. Squeeze grip sensor 5 times, for 2 secs each w/2 secs rest btwn squeezes.
3. Use only FINGERTIPS, not whole palm when squeezing
4. Each squeeze is strong than previous (e.g. squeeze 1 = very light, squeeze 2 = bit stronger… squeeze 5 = very strong squeeze)

Question 4

What is absolute integral? Units?

Answer 4

• Relative amt of electrical activity causing the muscle activity and grip strength
• Units = mV x second

Question 5

What is exercise 2

Answer 5

Muscle activity and Fatigue

Question 6

What is the aim of exercise 2

Answer 6

To OBSERVE the RELATIONSHIP btwn STRENGTH and LENGTH of CONTRACTION TIME of a MUSCLE and EMG activity

Question 7

Procedure for exercise 2

Answer 7

1. Subject sit quietly w/dominant forearm resting on table top
2. Squeeze bulb as HARD as they can (using only FINGERTIPS)
3. Squeeze as LONG as they can, hold for at least 1 min but no longer than 2 min
4. Stop recording when subject released bulb AND max grip strength dec at least 50% the max squeeze at beginning

Question 8

What is exercise 3

Answer 8

EMG activity while Arm Wrestling

Question 9

What is the aim of exercise 3 (EMG while Arm Wrestling)

Answer 9

To STUDY the EMG ACTIVITY in MUSCLES that WORK while simulating WINNING or LOSING during ARM WRESTLING

Question 10

Time for exercise 3

Answer 10

15 mins

Question 11

Procedure for exercise 3

Answer 11

1. Locate muscles of forearm and upper arm. Flex or extend and note areas where muscles are tense for ease.
   * Clean skin with alcohol
2. Place 1 pair electrodes over PRONATOR TERES MUSCLE on ANTERIOR surface of forearm. Pair placed side by side, with 2-4cm btwn them, on length of muscle as it crosses inner forearm. Attach RED (+1) lead to the electrode closer to thumb, on lateral edge of arm. Attach BLACK (-1) lead to electrode closer to elbow.
3. 2nd pair of electrodes over BICEPS BRACHII on UPPER ARM. 1st electrode placed 4cm above elbow. 2nd electrode 2-4cm above the first, towards shoulder. Attach WHITE (+2) lead to electrode near elbow. Attach BROWN (-2) above +2 electrode.
4. FIFTH electrode (ground) placed on lower abdomen, just above waist, on right side. Attach GREEN lead.
5. Subject assume NEUTRAL POSITION with opponent, PERPENDICULAR to table.
6. Place softer surface under ELBOWS
7. Subject will assume “WINNING” position: slowly move arm while flexing muscle to push opponents hand towards table top. Don’t go further than half way. HOLD for 4 SECS, then relax.
8. Return to NEUTRAL position for FOUR seconds
9. Subject assume “LOSING” position: slowly have OPPONENT move his arm from neutral position, PUSHING SUBJECTS HAND BACK PAST NEUTRAL POSITION to HALWAY towards table top. HOLD for 4 SECS, then RELAX.
10. Return to NEUTRAL POSITION for at least TWO SECS
11. REPEAT CYCLE 2 more times

Question 12

What is exercise 4

Answer 12

EMG activity in Antagonistic Muscles in Forearm

Question 13

What is the aim of exercise 4

Answer 13

To STUDY EMG ACTIVITY in MUSCLES that work in OPPOSITION to each other to FLEX or EXTEND the HAND

Question 14

Time for exercise 4 EMG activity in antagonist muscles

Answer 14

30 mins

Question 15

Procedure for exercise 4 EMG activity in antagonist muscles

Answer 15

1. Locate muscles of forearm . Flex or extend and note areas where muscles are tense for ease.
   * Clean skin with alcohol
2. Place 1 pair electrodes over FLEXOR MUSCLES on ANTERIOR surface of FOREARM. 1st electrode placed 8cm below inside of elbow and 4cm from medial margin of forearm. 2nd electrode palced 8cm below other electrode along midline of anterior surface of forearm. Attach RED (+1) lead to the electrode closer elbow. Attach BLACK (-1) lead to electrode closer to middle of forearm.
3. 2nd pair of electrodes over EXTENSOR MUSCLES on POSTERIOR SURFACE of forearm. 1st electrode placed 9cm below tip of ELBOW along midline. 2nd electrode placed 6cm below 1st electrode and 3cm from lateral margin. Attach WHITE (+2) lead to electrode near elbow. Attach BROWN (-2) to electrode closest to middle of forearm.
4. FIFTH electrode (ground) centered btwn positions of all 4 electrodes. Attach GREEN “C” lead to electrode.
5. Before recording, subject extend arm in front of body w/palm upward aka NEUTRAL position. Keep HAND OPEN during recording.
6. Move hand UPWARD (FLEXION) from neutral, as far as possible and hold for FOUR SECS
7. Return to neutral for FOUR SECS
8. Move hand DOWNWARD (EXTENSION) as far as possible and hold for FOUR SECS
9. Return to neutral for at least TWO SECS
10. Repeat cycle of flexion and extension TWO MORE TIMES
11. Repeat these steps TWO MORE TIMES while subject FORMING FIST

Question 16

What is exercise 5

Answer 16

Antagonist muscles doing work

Question 17

What is the aim of exercise 5 antagonist muscles doing work

Answer 17

To STUDY the EMG ACTIVITY in MUSCLES that LIFT WEIGHT by FLEXION or EXTENSION

Question 18

Time for exercise 5

Answer 18

~20 mins

Question 19

Procedure for exercise 5

Answer 19

SAME SET UP AS EXERCISE 4:

1. Locate muscles of forearm . Flex or extend and note areas where muscles are tense for ease.
   * Clean skin with alcohol
2. Place 1 pair electrodes over FLEXOR MUSCLES on ANTERIOR surface of FOREARM. 1st electrode placed 8cm below inside of elbow and 4cm from medial margin of forearm. 2nd electrode palced 8cm below other electrode along midline of anterior surface of forearm. Attach RED (+1) lead to the electrode closer elbow. Attach BLACK (-1) lead to electrode closer to middle of forearm.
3. 2nd pair of electrodes over EXTENSOR MUSCLES on POSTERIOR SURFACE of forearm. 1st electrode placed 9cm below tip of ELBOW along midline. 2nd electrode placed 6cm below 1st electrode and 3cm from lateral margin. Attach WHITE (+2) lead to electrode near elbow. Attach BROWN (-2) to electrode closest to middle of forearm.
4. FIFTH electrode (ground) centered btwn positions of all 4 electrodes. Attach GREEN “C” lead to electrode.
5. Subject rest forearm on flat surface with palm up
6. Place weight (2-3kg) in palm of subject. Record EMG activity as subject LIFTS weight by FLEXION. HOLD for FOUR SECs. Return weight to table top for FOUR SECS. REPEAT SECOND TIME.
7. Subject rest forearm on flat surface with PALM DOWN.
8. Subject grip same weight. Record EMG as subject LIFTS weight by EXTENSION. Subject raise and hold for FOUR SECs then return weight to table top for FOUR SECs. REPEAT SECOND TIME.

Question 20

What is exercise 6

Answer 20

To study MUSCLES WORKING in OPPOSITION to each other to MAINTAIN BALANCE WHILE STANDING

Question 21

Time for exercise 6

Answer 21

30 mins

Question 22

Procedure for ex 6 Antagonistic muscles in lower leg

Answer 22

1. Locate muscles of lower leg. Dorsiflex or plantarflex and note areas where muscles are tense for ease.
   * Clean skin with alcohol
2. Place 1 pair electrodes over TIABIALIS ANTERIOR. 1st electrode placed 10cm BELOW KNEE on MIDLINE of muscle. 2nd electrode placed on MIDLINE of muscle, 10 cm BELOW FIRST electrode. Attach RED (+1) lead to the electrode on UPPER portion of TA. Attach BLACK (-1) lead to electrode MIDDLE portion of TA.
3. 2nd pair of electrodes over GASTROCNEMIUS (CALF muscle) on back of lower leg. 1st electrode placed 8cm below back of knee, along midline of calf muscle. 2nd electrode placed 10cm BELOW FIRST. Attach WHITE (+2) lead to electrode near BACK OF KNEE. Attach BROWN (-2) to electrode MIDDLE of CALF.
4. FIFTH electrode (ground) placed INSIDE LOWER LEG just ABOVE ANKLE. Attach GREEN “C” lead to electrode above ankle.
5. Subject should be sitting.
6. Subject will alternate btwn PLANTAR FLEXION and DORSIFLEXION.
7. Subject will STAND ERECT ON BOTH LEGS. Then rock feet from HEELS to TOES and back to HEELS ON BOTH LEGS, 4 TIMES (HOLD for ONE SEC on HEELS and TOES)
8. Subject continue rocking back and forward, 4 times, while putting MORE WEIGHT on LEG with ELECTRODES.
9. Subject STANDS ON ONE FOOT and remain MOTIONLESS.
10. Subject SQUAT (DORSIFLEXION) and STRETCH UPWARD ON HIS TOES (PLANTAR FLEXION)