Understanding Skeletal Muscle Contraction Physiology Essay

Understanding Skeletal Muscle Contraction Physiology Essay Introduction Muscle contractions are a result of the buildup of tension within the muscle, and for muscles to contract, they must have a continuous supply of energy in the form of a molecule called adenosine triphosphate or ATP (Silverthorn, D.U., 2010). Through muscle contractions, we are able to run, walk, lift, push, sit, and even chew our food (Stabler, et.al, 2009). In addition to an energy requirement, skeletal muscles must be stimulated to contract (Stabler, et.al, 2009). Skeletal muscles are stimulated from an action potential that originates from within motor neurons (Stabler, et.al, 2009). Motor neurons are those that send electrical signals to skeletal muscle cells (Stabler, et.al, 2009). An action potential is the electrical signal that occurs when positively charged ions flood into the motor neuron as a result of a chemical, electrical, or other type of stimulus (Stabler, et.al, 2009). This signal, an area of intracellular positivity, self propagates down the length of the neuron tow ards the muscle cell (Silverthorn, D.U., 2010). Once this signal reaches the muscle cell, it is converted into a muscle contraction through a process called excitation-contraction coupling (Stabler, et.al, 2009). The interior of muscle cells also becomes very positive resulting in a muscle contraction. Muscle contractions have 3 different phases which include the latent period, contraction phase, and the relaxation phase (Silverthorn, D.U., 2010). The latent period occurs between the start of an action potential and the beginning of a muscle contraction (Stabler, et.al, 2009). This is the phase that will be studied later. The contraction period begins at the end of the latent period and ends when muscle tension ends (Stabler, et.al, 2009). The relaxation period occurs begins at the end of the contraction period until the muscle becomes free of tension (Stabler, et.al, 2009). To initiate a muscle contraction, the stimulus must reach its threshold. This is the minimal stimulus required to generate the action potential within a muscle cell causing the internal cellular environment to become positive (Stabler, et.al, 2009). In addition, the change in stimulus intensity can play a role in how strongly the muscle generates force when it contracts which is referred to as the active force (Stabler, et.al, 2009). As a stimulus is repeatedly applied to a muscle, fatigue will eventually occur. Fatigue can refer to a deficit in muscle functioning or a gradual decline in the force sustained by a muscle (Enoka and Duchateau, 2008). Other research has shown that fatigue could be the result of metabolic changes that occur within the contractile mechanisms within the muscle fibers such as changes in ion concentrations (Allen and Westerbland, 2001). If the latent period length is dependent upon the strength of the stimulus, increasing the electrical stimulus intensity should also increase the latent period, and since a threshold stimulus needs to be reached for a contraction to occur, then there will be a minimal amount of electrical stimulation required to generate a muscle contraction. In addition, if the active force strength is dependent upon the strength of the stimulus intensity, an increase in stimulus intensity should increase the active force. If muscle fatigue is occurring due to repeated stimuli over a period of time, then applying a stimulus at a constant rate should result in a decrease of sustainable force within the muscle. These experiments will be carried out using an electrical stimulus by passing a known amount of voltage through an isolated skeletal muscle attached to a metal holder that will transmit the data to a recorder and an oscilloscope screen for analyses (Stabler, et.al, 2009) Materials and Methods In order to understand muscle contraction physiology, I evaluated 4 different experiments. The first 3 experiments were designed to use a single stimulus to evaluate the latent period of a muscle contraction, to evaluate the threshold stimulus of a muscle contraction, and to evaluate the effects of increased stimulus intensity on a muscle contraction. The fourth experiment was designed to demonstrate the effects of muscle fatigue. The following materials were used for these experiments: an isolated skeletal muscle (75mm in length), a metal holder to measure force generated by the skeletal muscle, an oscilloscope, an electrical stimulator (single and multiple stimulus), and a data collection box. The first experiment was designed to determine the latent period of a muscle contraction. First, the muscle was attached to the metal holder. The electrode from the electrical stimulator was rested on the surface of the muscle. The electrical stimulator was set to 6.0 volts. A muscle contract ion was induced by applying a single electrical stimulus using the electrical stimulator. The data generated a tracing on the oscilloscope screen which was used to determine the latent period by selecting the point where the flat line began to rise. The data were recorded using the data collection box. I repeated this experiment using the following voltages: 1.0 volts, 3.0 volts, and 10.0 volts. These voltages were used to see if changes occurred within the latent periods. For the second experiment, the data generated was used to determine the threshold voltage. The threshold voltage occurred when the active force measured in grams was greater than 0. The equipment setup was the same as the last experiment, and the electrical stimulator was set to 0.0 volts. At 0.0 volts, the muscle was stimulated and the results observed and recorded using the oscilloscope and data recorder respectively. This experiment was repeated multiple times by increasing the voltage by 0.1 volts until the mi nimal threshold voltage was determined. For the third experiment, the effects on muscle contractions due to an increase in the electrical stimulus intensity were explored. Again the same equipment setup was used. The initial voltage was set to 0.5 volts followed by stimulation of the skeletal muscle. The data were observed and then recorded. This experiment was repeated multiple times by increasing each subsequent voltage by 0.5 volts. This continued until the data showed there was no change in the increase in active force. For the final experiment, fatigue was induced in the skeletal muscle. The equipment setup for this experiment was similar to the first three experiments. However, a different electrical stimulator was used which incorporated a multiple stimulus option as well as a single stimulus option. The multiple stimulus option added the ability to start and stop the stimulus activity. This experiment was designed so that several stimuli per second were being applied to the skeletal muscle if so desired. The electrical stimulator voltage was set to 7.0 volts, and the number of stimuli per second was set to 100. The muscle was then stimulated for approximately 400 seconds by selecting the multiple stimulus option, and the graphical data were recorded from the oscilloscope. Results For experiment one, the latent period was recorded in milliseconds and was compared to its corresponding stimulus voltage. The time measurement (latent period) reflected the start of the flat line until it began to rise. Below is a summary of the recorded data. Latent Period Determination Stimulus Voltage (V) Latent Period (msec) 1 3.89 3 2.78 10 2.22 For experiment two, the threshold stimulus determination data was collected by measuring the electrical stimulus voltage and its corresponding active force generated. Once the active force became greater than 0, the experiment was stopped. Below is a table with the collected data. Threshold Determination Stimulus Voltage (V) Active Force Generated (gms) 0 0 0.1 0 0.2 0 0.3 0 0.4 0 0.5 0 0.6 0 0.7 0 0.8 0.02 For experiment three, the data were collected in order to determine the effects of increased stimulus voltage on muscle contractions. The data reflected 0.5 volt interval increases in the electrical stimulus until 10 volts were reached. Below is the summary of the data. Muscle Contractions Increased Stimulus Effects Muscle Contractions Increased Stimulus Effects Stimulus Voltage (V) Active Force Generated (gms) Stimulus Voltage (V) Active Force Generated (gms) 0.5 0 5.5 1.59 1 0.15 6 1.65 1.5 0.43 6.5 1.7 2 0.66 7 1.74 2.5 0.87 7.5 1.78 3 1.04 8 1.81 3.5 1.19 8.5 1.82 4 1.32 9 1.82 4.5 1.42 9.5 1.82 5 1.51 10 1.82 For experiment four, data was graphed in order to demonstrate the effects of fatigue. The rate of the multiple stimulus was 100 stimuli/second at a constant setting of 7.0 volts. The data were recorded over a 400 second interval. Below is a graphical representation of the collected data. Muscle Fatigue Effects of Prolonged Stimuli Over Time (Stabler, et.al, 2009) C:Sheas StuffHuman PhysiologyFatigue.jpg Citations Allen, D.G. and H. Westerbland. (2001). Topical Review: Role of phosphate and calcium stores in muscle fatigue. Journal of Physiology 536.3: 657-665. Enoka, R. and J. Duchateau. (2008). Muscle Fatigue: what, why and how it influences muscle function. Journal of Physiology 586.1: 11-23. Silverthorne, D.U. 2010. Human Physiology: An Integrated Approach. 5th Edition. Pearson Benjamin Cummings, pp. 408-422. Stabler, T., Smith, L., Peterson, G., and Lokuta, G. 2009. PhysioEx 8.0 for Human Physiology à ¢Ãƒ ¢Ã¢â‚¬Å¡Ã‚ ¬ Laboratory Simulations in Physiology. pp. 17-22.

Proposal for a Fitness Center in TI Essay -- Texas Instruments Health

Proposal for a Fitness Center in TI An on-site fitness center for Texas Instruments will prove to be advantageous to the company as well as its employees. Studies show that employees who exercise regularly are more productive, efficient, and pleasant to work with. Texas Instruments has the capability to increase employee retention, recruitment, and revenues by investing in a fitness center through Health Fitness Corporation. Health Fitness Corporation provides on-site fitness centers for numerous prestigious companies such as Best Buy and Federal Express. The positive relationships and results have more than qualified Health Fitness Corporation to provide Texas Instruments with a unique facility, designed to meet all of their personal needs. Among Health Fitness Corporation’s services are state-of-the-art equipment, the latest healthcare products, a knowledgeable staff, specialty classes, and employee incentive programs. The project will be divided into four phases, each with a certain purpose and timeline to achieve a specific goal. †¢Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Phase I (Research and Development) - This four month phase will involve evaluating the needs and desires of Texas Instruments’ employees. †¢Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Phase II (Bidding and Structural Construction) - This five month phase involves choosing the right contractor and building the facility. †¢Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Phase III (Interior Development) - This two month phase will involve renovating the interior of the facility to meet Texas Instruments’ custom desires. †¢Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Phase IV (Trial Period) - This one month process involves staffing the facility and providing training on the exercise equipment. Health Fitness Corporation offers two standard packages. Package A is less expensive to implement, but Package B offers greater revenues. After analyzing Texas Instruments, we believe that Package B will be the most beneficial to the company. Not only will this investment improve the financial status of Texas Instruments, but it will also develop stronger employee relationships. For each dollar Texas Instruments invests in this project, they will realize a greater increase in employee productivity. Many forward-thinking corporations are offering on-site fitness centers to their employees. Texas Instruments must join this trend or their company will be left behind in employee recruitment and retention. Health Fitness Corporation can h... ...ly expanded and is becoming much more than mere fitness centers, but major sources of revenue for companies as well. Health Fitness Corporation has assisted many companies in increasing both recruitment and employee retention. In today’s fast-paced, competitive business world, companies who do not innovate are left behind. Texas Instruments cannot allow these other corporations to gain a competitive advantage. Health Fitness Corporation can provide Texas Instruments with a facility that will not only compete with other companies, but will also offer special programs, products, and training that will separate Texas Instruments from the competition. Health Fitness Corporation looks forward to the commencement of this project and a long and rewarding relationship with Texas Instruments. Works Cited British United Providence Association [online]. Available:   Ã‚  Ã‚  Ã‚  Ã‚  hcd2.bupa.co.uk/fact_sheets/html/exercise.html [2004, April 22] Georgia State University Exercise and Physical Fitness Page [online]. Available:   Ã‚  Ã‚  Ã‚  Ã‚  www.gsu.edu/~wwwfit/benefits.html [2004 April, 24] Hoover’s The Business Information Authority [online]. Available:   Ã‚  Ã‚  Ã‚  Ã‚  www.hoovers.com [2004 April, 18]

Advertising Essay

Every day, whether watching tv, listening to the radio, or driving in the car, people encounter all sorts of advertisements. For as long as most can remember, advertising has been all over the place, and over time it has weaved its way into the day to day lives of society. The use of advertising is to grab one’s attention and to persuade them of something, usually to buy a service or a product. And whether we realize it or not, negatively or positively, advertisements affect people psychologically. Some of them use bright colors, others use statistics, and some use humor to grab one’s attention. One such advertisements comes from the gym, Planet Fitness. Planet Fitness attracts members by use of humor and by appealing to the physical and financial needs of the ‘average joe’ in their advertisements. In this commercial, there are young, fit women walking around the locker room talking about how hot they are and how hot they think each other are, all the while a normal woman of a little older age sits in her towel and witnesses their conversation. You can tell that she’s clearly uncomfortable with being in the situation. She then goes on to tell the fitness instructor â€Å"†¦ And that’s why I don’t like gyms† and the instructor responds with â€Å"Well, we’re not a gym. We’re Planet Fitness†. So they understand that not everybody that goes to the gym is a big muscled hunk, and that sometimes it can be a little uncomfortable being around people that are like that. The way that Planet Fitness is built and the way in which they carry themselves, is that they make the customer feel that they are what’s most important to the company. They care about making you feel comfortable while being able to exercise in a public gym. Planet Fitness also understands that not everybody is made up of extra money. This is taken from the Planet Fitness website, â€Å"We don’t have any salespeople, and we don’t bother with all the extras like juice bars and childcare that drive up costs and can make a gym membership seem more like a car payment. Instead, we’ve boiled our business down to the things that you really want in a health club – clean, stylish, hassle-free facilities that are filled with tons of brand-name cardio and strength equipment, and a lot of happy people. If you’re looking for a comfortable, friendly place to exercise, and like a great deal, then you’ll love Planet Fitness. † (http://www. planetfitness. com/About-Planet-Fitness-Gym). They offer memberships for just ten dollars a month, which is an amazing bargain compared to other big name gyms such as the YMCA or 24 Hour Fitness. By offering cheap rates, it creates a great incentive for somebody to exercise at Planet Fitness. Lastly, Planet Fitness seems to appeal to women in this advertisement. It’s socially acceptable to say that women are looked at as being more sensitive than men when it comes to their appearance and body image. So in this particular ad, they show that the â€Å"normal† woman is very very uncomfortable in the locker room and it’s actually a deal breaker for her when it comes to going to the gym. So by showing this advertisement, Planet Fitness can attract more female customers just by letting them know that they won’t be judged at the gym and they can exercise with a peace of mind. With all this being said, it can be concluded that the advertisement by Planet Fitness is a successful one. By appealing to people’s wallets and through their understanding of the â€Å"comfort zone†, and having humorous commercials, they’ve established credibility with the public as being a welcoming, friendly gym all at a low cost.

Issues In Our Society essays

Issues In Our Society essays Psychology is the scientific study of human and animal behavior. It is made of theories and tries to prove why we behave the way we do, our mental processes, our emotions, and our actions. In this writing assignment I will discuss why some people choose to behave so outrageous that we see it as abnormal self-destructive behavior and why others try to fit in this society and follow the rules. In the United States theres people from all over the world from different cultures and traditions. I will give my personal opinion on some of the issues and controversies in our country. My first issue is about drugs. Many people feel that certain illegal drugs like heroin, marijuana, and cocaine should be legalized. I think its a crazy idea, people feel that is they legalize it at first we would buy it but then we would get bored and the use will decrease, but how many lives will be lost? Is it worth taken a chance? I dont think so, tobacco is legal and people dont get tired of smoking, so if they legalized these drugs more and more people will get addicted. The effects of any drug depend on several factors like the amount taken the users past drug experience, the manner in which is taken, and circumstances. Heroin is a highly addictive drug derived from morphine, which is obtain from the opium poppy. It is a downer that affects the brains pleasure systems and interferes with the brains ability to perceive pain. Heroin can be injected into a vein or a muscle, smoked in a water pipe, inhale as smoke through a straw or snorted as powder via the nose. Cocaine is a powerful central nervous system stimulant that heightens alertness, inhibits appetite and the need for sleep, and provides intense feelings of pleasure. Cocaines short-term effects appear soon after a single dose. Marijuana is usually smoked as a cigarette or in a pipe or a bong. If you have a job a...

Business Organization Basics

Business Organization Basics Introduction The retail industry has been one of the globally competitive industries among other industries. Despite that the retail industry is primarily associated with the small of goods in small quantities to the final consumers, large companies and business entities have taken up the race into the industry. This phenomenon has been highly witnessed in developed and developing economies like the US, China, Brazil and UK, whereby the retail industry is overwhelmed by large companies.Advertising We will write a custom research paper sample on Business Organization Basics specifically for you for only $16.05 $11/page Learn More This phenomenon is associated with the lucrative nature of the industry as compared to other business ventures. The retail health care management has been the most distinctive in the global market whereby it offers diverse opportunities. A point worth of consideration is that the levels of competition in the industry have magnified o ver the last couple of decades. This has forced the operating businesses to adopt the most competitive strategies. For instance, global marketing strategy has been one of the mostly adopted strategies in the retail business. The case of CVS Caremark has been of great importance as far as the health care retail industry is concerned. In this case, CVS Caremark has been a leading player in the retail health care management industry is concerned, whereby it has demonstrated commendable competency. The marketing strategy of the company has also been efficient thus enhancing its competitiveness in global markets. The operations of CVS Caremark in the retail industry are very explicit. In this case, CVS Caremark operates a chain of retail pharmaceutical shops in varied formats in different markets including the US. The products and services dealt with by this company are vividly retail in nature in the sense that the company focuses on the final consumers (GICS, 2011). Basically the compa ny deals with pharmaceutical products which are aimed at boosting the health of the community. This is a clear demonstration that CVS Caremark is operating in the retail industry. The success of the company has been clearly demonstrated by its rapid growth and expansion in the US markets (CVS CAREMARK, 2011). The success and competitiveness of CVS Caremark is closely influenced by its strong mission and vision statements. The company’s mission statement is a vital tool in driving the operational and marketing forces within the company. The brands as well as the industry in which the company operates are adequately incorporated into the mission statement. This has played a vital role in enhancing the competitiveness of the company. CVS Caremark has a very admirable mission statement which reads as; â€Å"We provide expert care and innovative solutions in pharmacy and health care that are effective and easy for our customers.† This is the mission statement as well as slo gan of the company which has been adequately adopted in enhancing the marketing operations of the company.Advertising Looking for research paper on business economics? Let's see if we can help you! Get your first paper with 15% OFF Learn More The mission statement is primarily aimed at boosting its brands by demonstrating compassion and commitment of the company to its people. This is a very strong mission statement which has not only helped in selling the company’s products but has also helped in positioning it (CVS CAREMARK, 2010). The choice of this company is based on its strong culture, core values and competence in the market. The company has been named the market leader in the health care management. This is based on its extemporary performance as well as admirable organizational culture and marketing efficiency. The company’s strong sense of compassion to the people’s needs is distinct in its positioning in the industry. In this case, the company is aimed at ensuring that the health of the people is guaranteed. Being the largest pharmacy health care provider in the US, CVS Caremark is very distinctive and positioned in the market (CVS CAREMARK, 2010). Conclusion In summation, the discussion and analysis of the CVS Caremark Company has demonstrated a high sense of competence. The company is ranked the market leader in the retail health care management industry. This is closely attributed to the company’s strong culture as well as mission and vision. The marketing strategies adopted by the company are also admirable thus making it competitive and a key market leader. References CVS CAREMARK (2010). Our Vision, Mission and Values. Web. CVS CAREMARK (2011). CVS Caremark Company. Web. GICS (2011). Global Industry Classifications Standards. Retrieved from: https://www.msci.com/gicsAdvertising We will write a custom research paper sample on Business Organization Basics specifically for you for onl y $16.05 $11/page Learn More

Sexual Harassment Research Paper Example | Topics and Well Written Essays - 500 words

Sexual Harassment - Research Paper Example 222). Shifting paradigm of globalization and liberalization in the society has increased the women’s participation in the work force to contribute to family income. Women are then endangered to sexual harassment which is, perhaps, as old as the very existence of women and this is one of those problems which discourage them in taking active part in economic and social development of the society (Naveed et al. 222). The increasing cases of sexual harassment today also increased the awareness of the society, thus, more and more women came out to make legal cases against their harassers. What are the factors that affect or determine sexual harassment? One of the known factors that determine sexual harassment would be that of gender. Research has shown that a person’s gender impacts his or her perceptions of sexual harassment. Moreover, women are often more sensitive than men to what constitutes sexual harassment and they often judge the same behavior to be more serious (Fiedler and Blanco 276). So, what was offensive to a woman may not be that of a deal to a man and they usually do not file a case as compared to that of women. In addition to this, culture was also identified as a factor. Different countries have different cultural takes on sexual harassment and, therefore, would have different laws about it. Perceptions on what constitutes sexual harassment vary among and within societies; somehow they depend on how people are socialized within that society, the existence of gender stereotypes, and set notions and hierarchies that may exist in the workplace. And it is because of these reasons that make it hard to compile a list of harassing conduct that should be prohibited. Some acts are easily identified as harassment, like kissing, fondling and physical contact with genital areas, while many other kinds of verbal, non-verbal, physical conduct may not (AWARE 11). The victims

Critically evaluate a UK based company of your choice in relation to Essay

Critically evaluate a UK based company of your choice in relation to how successful they are at social marketing - Essay Example price, product, promotion and place. Various strategic models, tools and concepts are made to enhance the effectiveness of overall strategic formulation. This paper will attempt to discuss about social marketing followed by an UK based company and how its social marketing has contributed to the success of the company. The Marks & Spencer is UK based company that has been selected for this report. At first, this essay will present a brief introduction of the Marks & Spencer followed by the discussion on social marketing strategy of the company. The next section will discuss about the competitors’ move in respect of social marketing comparing the Marks & Spencer. Finally, proper recommendations will be provided in order to bring improvement in social marketing strategy for obtaining term sustainable competitive advantage. ‘Social marketing’ is a concept that concentrates on communicational and promotional aspect of marketing. As per the Social Marketing Institute, â€Å"social marketing is the planning and implementation of programs designed to bring about social change using concepts from commercial marketing† (Social Marketing Institute, â€Å"Social Marketing†). According to Kotler Roberto and Lee, â€Å"social marketing is the use of the marketing principles band techniques to influence the target audience to voluntarily accept, reject, modify, or abandon a behavior for the benefit of individual, groups or society as a whole† (Kotler Roberto and Lee, p.5). Social marketing is meant to bring social changes to its targeted groups. Social marketing can be used to achieve profit making or non-profit making organizational goals. The social marketing is basically customer, client or audience centered. Therefore, for successful social marketing, it is very necessary to identify the appropriate and potential group and to develop proper communication for increasing the effectiveness. For planning and