BIOL104 CTCWVUT Dominant Hand Worksheet

Please view explanation and answer below.Hypothesis 1: I speculate that the dominant hand will have a stronger signal.Hypothesis 2: EMG signal will increase as the weight being lifted gets heavier.Hypothesis 3: The dominant hand will experience longer fatigue than the non-dominant hand.Step 5: Questions and DiscussionEMG Ia.Explain the source of the signals detected by the EMG electrodes. (HINT: think about energy in the human body)The EMG electrodes pick up signals from the electrical activity of the muscles, and the action potentials propagateD along the sarcolemma.b. The dominant hand’s clench is stronger than the non-dominant hand. A study found a statistically significant difference between the grip strengths of dominant and non-dominant hand in favor of dominant. The results on table two also show the same results.Reference: Incel NA, Ceceli E, Durukan PB, Erdem HR, Yorgancioglu ZR. Grip strength: effect of hand dominance. Singapore Med J. 2002 May;43(5):234-7. PMID: 12188074.The term “size” of a motor unit usually refers to the amplitude of the motor unit action potential (MUAP), in an EMG study. In common terms, the later recruited type II fibers have larger diameter muscle fibers generating higher potentials than the smaller, slow twitch type I units. Because of the small uptake area of standard EMG needle electrodes, however, the size of consecutively recruited MUAPs during an EMG study varies considerably.Reference: Friedhelm Sandbrink, M. D. (2021, October 13). Motor unit recruitment in EMG: Definition of motor unit recruitment, order of recruitment, assessment of recruitment at low level of muscle contraction. Motor Unit Recruitment in EMG: Definition of Motor Unit Recruitment, Order of Recruitment, Assessment of Recruitment at Low Level of Muscle Contraction. Retrieved May 5, 2022, from https://emedicine.medscape.com/article/1141359-ove… a. The dominant hand’s max clench force is higher than the non-dominant hand.b. It might be genetic or might come from years of preferred use.Yes. From table 6 alone, it can be seen that the force at peak and integrated EMG of the dominant hand is much higher than the non-dominant one.EMG IIa. The dominant hand.b. The 50℅ of Max Clench Force and the Force at peak of the dominant hand is much higher than the result of the non-dominant hand.a.Yes.b. Yes they are the same motor units that are being used because continuously holding an object requires the same motor units.Fatigue has affected the timing of my recording because I had to record a lot of times, my arms got tired and I needed to rest my arms a bit because if I don’t, the results will not be as accurate as I want them to be.They both perform the same amount of work which is 200kg*cm.Yes, based on tables 5, 6, and 7. Based on my observations, more force is needed to lift heavier objects, in which the dominant hand exerts more, which then leads to higher mV or integrated EMG. The results on table 6 back my hypothesis that the dominant hand will have longer fatigue.Try pushing up dumbbells for a specific amount of time and specific times consecutively with both the dominant and non-dominant hand. Then, gather clench fist data experiments.

Week 7: Muscle and EMG Lab

Instructions
Step 1. Download “BSL Analysis 4.1” – This is optional but it gives you the
opportunity to use Biopac for data analysis. Watch video from the following link:
https://www.youtube.com/watch?v=HTbD5v87WQg
following instructions, download software to your computer.
Step 2. Read “Introduction” section –on pages 2-3 of this document.
Step 3. Watch the EMG 1 Exercise – the data and explanation for this exercise are
found on page 4-5. This YouTube video demonstrates how the data is acquired from a
test subject: https://www.youtube.com/watch?v=Jix60_XnwjQ
Step 4. Watch the EMG 2 Exercise – the data and explanation for this exercise are
found on page 6-7. This YouTube video demonstrates how the data is acquired from a
test subject: https://www.youtube.com/watch?v=xQuoaaxMrMA&t=509s
Step 5: Questions and Discussion – answer questions starting on page 8. Please
hand in 1 copy per group and be sure to include the names of all active participants.

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Week 7: Muscle and EMG Lab
Step 2: Read Introduction
Electromyography (EMG) uses electrodes to
detect the electrical signal produced by your
skeletal muscle. All cells possess a distribution
of electrolytes that is usually more negative
inside the cell and more positive outside the cell
(Fig. 1). The movement of these electrolytes into
or out of t…