Muscle Flexion Lab Report

Using electrodes on the bicep to record the motor unit recruitment during all four conditions: control, stretching, cardio, and aerobic stretching. As shown in figure 5, the control group and the stretching are similar in the amount of EMG amplitude (mV). However, when comparing stretching with both cardio and aerobic stretching there is an increase as the intensity of the warm-up. Moreover, aerobic stretching has the highest EMG amplitude, which shows that there is motor unit cycling. Motor cycling provides a more efficient performance on the bicep because more of the muscle is being used (Widmaier, et al.,

Introduction: Exercise is a physical activity or particular movement that is used in order to become healthier and stronger. (1) Exercise, in all of its forms, has various effects on the different systems in the human body. One of the main benefits is cardiovascular health, including circulation and heart health. Exercise uses a lot of energy, which the cells derive from oxidising glucose. Meaning that the heart has to work harder to pump more blood throughout the body and the heart has to beat faster in order to achieve a high effort. (2) The heart benefits from exercise include being able to pump more blood through the body and continue working at a higher level with less strain. (3)

The EMG signal that is observed through the placement of electrodes on the skin is closely coupled with the generation of muscle force. In normal conditions, the force-EMG relationship is either linear or the increase in EMG at low force levels is less than proportional (Semmler 2014). However, a different force-EMG relationship was observed following eccentric exercise,

The current study used symmetry index as an indicator of coordination but no differences were found between the conditions. Another measure of coordination has been seen in research using electromyography (EMG) and it has been shown that external AF cues lead to efficient muscular contraction and better motor control performance. For example, Zachery et al. had participants shooting free-throw tasks under both internal and external AF conditions. EMG activity was measured from the biceps and triceps of the shooting arm. Their results demonstrated that with external focus shots were more accurate and EMG activity was lower with biceps and triceps19. In another study, Wulf et al. had participants complete the vertical jump-and-reach task and measured their jump height and EMG activity of lower-limb musculature. Their findings showed participants jumped higher and had EMG activity generally lower when focusing attention externally compared to focusing attention internally20. Lastly, Marchant et al. had participants complete isokinetic elbow flexion contractions using a Biodex. Authors reported a net joint torque at the elbow was larger and the EMG activity of the bicep brachii was decreased under external AF conditions 21. None of the studies above measured force production but claim enhanced neuromuscular control allowed for greater force generation. Therefore, when directing attention externally during max force generation tasks, muscle coordination patterns are optimized producing more efficient and effective

A) CURRENT STATE OF KNOWLEDGE Vascular smooth muscle cells (VSMC) and extracellular matrix (ECM): Blood vessels, include arteries that transport blood from the heart to the systemic circulation, and veins that transport blood back again into the heart. A remarkable change in blood vessel structure and function happened, with the emergence of a high-pressure, pulsatile circulatory system in vertebrates. Blood vessels then evolved from simple tubes for channeling blood or other body fluids from a low-pressure heart. According to their sizes and structures, arteries can be subdivided into four categories: large elastic arteries, medium-sized muscular arteries, small arteries (s Law, the larger the aortic diameter, the larger the wall tension

Electromyography (EMG) is a way of measuring muscle electrical activity and use it in medical diagnoses which refers to muscle performance. The electric activity generated during muscle activation, known as the myoelectric signal, is generated from small electrical currents generated by the exchange of ions across the muscle membranes and detected with the help of surface electrodes [1].

higher the hertz, the more cycles the sound wave goes through a second. The higher the

This is an example triceps. This muscle covers the olecranon bone (which exerts force on the applied force) and arm (resistance) elbow (center). First class levers have a balance between speed and power.

Muscle contraction begins when the nervous system generates a signal. A motor neuron conducts an action potential to the link with the muscle fiber at the neuromuscular junction a neurotransmitter called acetylcholine is released. This chemical then binds to receptors on the muscle fibers. Acetylcholine receptors are chemically gated ion channels. When Acetylcholine binds it opens and allows an influx of sodium ions into the muscle fiber. This stimulates the sarcolemma and generates another action potential that travels through tiny folds knows as transverse tubules the action potential reaches myofibrils within the muscle fiber, surrounding the myofibrils are membranous sacs called the sarcoplasmic reticulum. The arrival of the action potential

Compared with systolic pressure, diastolic pressure has a rather mild increase when intensity of exercise increases.

Next let's measure the amount of flexion or bending of the elbow. Position the patient in the correct position to measure this motion. Now place the goniometer on the patient so the axis or center of the goniometer is in the correct position to measure elbow flexion, remember this motion is when the patient bends the elbow bringing the palm towards the

Some studies in the past have focused on the effect of speed on muscle activations and have reported a direct correlation between the two quantities21-23. It has been shown that an increase in the speed of walking results in an overall increase in muscle activity. However, this relationship does not hold for all ranges of speed and some deviations from it have been observed in lower speeds22. For instance, between 0.28 ms-1 and 0.83 ms-1 some subjects show decrease in the activity of biceps femoris (BF) with an increase in speed. The same phenomenon has been observed in rectus femoris (RF) in the range of 0.06 ms-1 and 0.28 ms-1. It has been suggested that the increase in muscle activity of some muscles at lower speeds is related to maintaining stability in the frontal plain. As the speed decreases the muscle synergies of gait become more similar to synergies in postural control tasks and this might explain the increase in muscle activations. This hypothesis has not been tested experimentally. It is not clear how muscle synergies might change for very slow speeds. This is of special interest since elderly population and patients with pathological gait walk with reduced

Determine who is the subject the person exercising and the experimenters and the person taking and recording the data the experimenters will take the subject standing heart rate temperature and breathing rate as well as make observation on the subject color and perspiration heart rate are obtained by taking the radial pulse or carotid pulse for 10 seconds convert all your heart rate to beats per minute by multiplying by 6 and record

The length of the biceps muscle changes with the angle. Muscle has a minimum length to which it can be contracted and a maximum length to which it can be stretched and still function. At these two extremes, the force the muscle can exert is much smaller. At some point in between, the muscle produces its maximum force. If the biceps pulls vertically (which is an approximation), the angle of the forearm does not affect the force required; but it does affect the length of the biceps muscle, which in turn affects the ability of the muscle to provide the needed

One subject was used, and was seated in the same position for each of the three tests performed. Because the patellar reflex is immediate, a video was taken during each tap with the hammer to visually compare the strength differences for each influence that was put into effect. This provided a steady, unwavering result with the option of repeated viewing for the conclusion of the experiment. After all three stages of the experiment were completed, the videos were reviewed for comparison between the baseline reflex and the three changing factors, along with any discrepancies and problematic areas that may have altered the results. The strength of the reflex was recorded as either equal to, more vigorous than, or less vigorous than the baseline reflex and the results were put into a simple chart.