task 8,9,10,11

Question 1

the speed (velocity) of contraction

Answer 1

v= s (mm) /t (ms)

s= change in muscle length
t= contraction time

Question 2

electromyography

Answer 2

potential differences from muscle contraction measured on the skin
electromyogram- potential differences as a function of time

Question 3

in the “stimulation-muscle fatigue”, in which nerve do we need to examine the minimal and maximal stimulus strength in humans

Answer 3

the ulnar nerve

Question 4

how to measure the minimal and maximal stimulus strength in humans

Answer 4

To determine the threshold potential apply single stimuli (“Number of Pulses”: 1) by clicking the “Stimulate” button. Increase the stimulus strength (“Pulse Current”, [mA]) gradually, and determine the minimal stimulus strength which just elicits a contraction.
By increasing the stimulus strength further, determine the weakest stimulus that just elicits a maximal contraction.

Question 5

how to examine the superposition in humans?

Answer 5

stimulate the ulnare nerve with supramaximal stimuli.determine the time interval needed to elicit superposition

Question 6

how to determine the incomplete tetany in humans?

Answer 6

apply supramaximal train stimulation over the ulnar nerve.

Question 7

How to calculate the muscle power?

Answer 7

P=force (N) x speed (m/s) = W (nm) / t (s)