Search results for: graded exercise

Authors: Sabrina Barsky, Ashley Monks

Abstract:

In humans, exercise improves symptoms of various pathological states, although exercise adaptations seem to differ in response to sex. Skeletal muscle anabolism is thought to be regulated by androgen receptor (AR) through poorly specified mechanisms. Interactions of AR and exercise on muscle phenotype remain inconclusive in males, and undetermined in females. We hypothesized that sex differences in exercise adaptations are regulated by the androgenic system and the type of exercise performed. Here we examined interactions between a muscle-specific AR overexpression transgene (HSA-AR) and forced aerobic exercise paradigm on muscle and adipose exercise adaptation in male and female rats. We used dual-energy X-ray absorptiometry (DXA) to examine body composition adaptations post 9-week exercise protocol. We replicated the effects of HSA-AR on body composition, with males only having increased % lean mass and reduced % fat mass (P<0.05). Aerobic exercise improved lean body phenotype significantly, with lesser indices of total and % fat mass (P<0.01) in both sexes. Sex-specific effects of exercise included decreased total body mass (P<0.01) in males and increased lean mass % (P<0.001) in females. Surprisingly, neither AR manipulation nor exercise affected bone parameters in either sex. This varied response in total mass and lean mass according to exercise presents a sexually dimorphic response to exercise. Neither sex showed an interaction between HSA-AR and forced aerobic exercise on body composition. Future work is proposed to examine the effects of exercise type (aerobic versus resistance) and the role of gonadal androgens in sexually dimorphic exercise-mediated mitochondrial adaptations. This work implicates the development of sex-specific exercise therapies.

Keywords: androgen receptor, forced exercise, muscle physiology, sexual dimorphism

Procedia PDF Downloads 93

Authors: Natural Frequency Analysis of a Porous Functionally Graded Shaft System

Abstract:

The vibration characteristics of a functionally graded (FG) rotor model having porosities and micro-voids is investigated using three-dimensional finite element analysis. The FG shaft is mounted with a steel disc located at the midspan. The shaft ends are supported on isotropic bearings. The FG material is composed of a metallic (stainless-steel) and ceramic phase (zirconium oxide) as its constituent phases. The layer wise material property variation is governed by power law. Material property equations are developed for the porosity modelling. Python code is developed to assign the material properties to each layer including the effect of porosities. ANSYS commercial software is used to extract the natural frequencies and whirl frequencies for the FG shaft system. The obtained results show the influence of porosity volume fraction and power-law index, on the vibration characteristics of the ceramic-based FG shaft system.

Keywords: Finite element method, Functionally graded material, Porosity volume fraction, Power law

Procedia PDF Downloads 173

Authors: Mohammad Soltani, Sajad Ahmadizad, Fatemeh Hoseinzadeh, Atefe Sarvestan

Abstract:

The exercise recovery is an important variable in designing resistance exercise training. This study determined the effects of passive and active recoveries on responses of platelet indices and hemodynamic variables to resistance exercise. Twelve healthy subjects (six men and six women, age, 25.4 ±2.5 yrs) performed two types of resistance exercise protocols (six exercises including upper- and lower-body parts) at two separate sessions with one-week intervening. First resistance protocol included three sets of six repetitions at 80% of 1RM with 2 min passive rest between sets and exercises; while, the second protocol included three sets of six repetitions at 60% of 1RM followed by active recovery included six repetitions of the same exercise at 20% of 1RM. The exercise volume was equalized. Three blood samples were taken before exercise, immediately after exercise and after 1-hour recovery, and analyzed for fibrinogen and platelet indices. Blood pressure (BP), heart rate (HR) and rate pressure product (RPP), were measured before, immediately after exercise and every 5 minutes during recovery. Data analyzes showed a significant increase in SBP (systolic blood pressure), HR, rate of pressure product (RPP) and PLT in response to resistance exercise (P<0.05) and that changes for HR and RPP were significantly different between two protocols (P<0.05). Furthermore, MPV and P_LCR did not change in response to resistance exercise, though significant reductions were observed after 1h recovery compared to before and after exercise (P<0.05). No significant changes in fibrinogen and PDW following two types of resistance exercise protocols were observed (P>0.05). On the other hand, no significant differences in platelet indices were found between the two protocols (P>0.05). Resistance exercise induces changes in platelet indices and hemodynamic variables, and that these changes are not related to the type of recovery and returned to normal levels after 1h recovery.

Keywords: hemodynamic variables, platelet indices, resistance exercise, recovery intensity

Procedia PDF Downloads 104

Authors: Nurul A. Hamzah, Tony Morris, Dan Van Der Westhuizen

Abstract:

Music listening can potentially promote the achievement of flow state during exercise. Selecting music for exercise should consider the motivational factors-internal factors (music tempo and musicality) and external factors (cultural impact and association). This study was a cross-over study which was designed to examine the motivational qualities of music (participant-selected music and researcher-selected music) and flow state responses during exercise accompanying with music. 17 healthy participants (M=30.2, SD=6.3 years old) were among low physical activity individuals. Participants completed two separate sessions of 30 minutes of moderate intensity exercise (40-60% of Heart Rate Reserve) while listening to music. Half the participants at random were assigned to exercise with participant-selected music first, and half were assigned to exercise with researcher-selected music first. Parameters including flow state responses (Flow State Scale-2) and motivational music rating (Brunel Music Rating Inventory-2) were administered immediately after the exercise. Results from this study showed that there were no significant differences for both flow state t(32)=0.00, p>0.05 and motivational music rating t(32)= .393, p>0.05 between exercise with participant-selected music and exercise with researcher-selected music. Listening to music either participant or researcher selected music could promote flow experience during exercise when music is perceived as motivational. Music tempo and music preference are factors that could influence individuals to enjoy exercise and improve the exercise performance.

Keywords: motivational music, flow state, researcher-selected music, participant-selected music

Procedia PDF Downloads 339

Authors: Catherine Cheetam, Alan Harper, Melody Elliott, Mika Ito

Abstract:

This paper describes a pilot study conducted with English as a foreign language (EFL) students at a private university in Japan who used graded readers and the MReader website in class or independently to enhance their English reading skills. Each semester students who read 100,000 words with MReader quizzes passed enter into the ‘MReader Challenge,’ a reading contest that recognizes students for their achievement. The study focused specifically on the attitudes of thirty-six EFL students who successfully completed the Challenge in the 2015 spring semester using graded readers and MReader, and their motivation to continue using English in the future. The attitudes of these students were measured using their responses to statements on a Likert scaled survey. Follow-up semi-structured interviews were conducted with eleven students to gain additional insight into their opinions. The results from this study suggest that reading graded readers in general promoted intrinsic motivation among a majority of the participants. This study is preliminary and needs to be expanded and continued to assess the lasting impact of the extensive reading program. Limitations and future directions of the study are also summarized and discussed.

Keywords: attitudes, extensive, intrinsic, methodolgies, motivation, reading

Procedia PDF Downloads 178

Authors: Amin Mehrabi, Mohsen Salesi, Pourya Pasavand

Abstract:

Context and objective: The purpose of this research is to study the effect of exercise time (morning/evening) on amount of Troponin T in males' plasma suffering from cardiovascular disease. Method: 15 cardiovascular patients selected as the research subjects. At 7 a.m. pretest blood samples taken from the subjects and they did the exercise protocol in presence of a doctor. Immediately after and 3 hours after that blood measurements done. A week later, the subjects did the same steps at 7 p.m. The SPSS v.20 software used to analyze data. Findings: This study proved that circadian rhythm does not have any effect on the response of myocarditis tissue to exercise and cardiovascular patients allowed to exercise in any times of a day.

Keywords: cardiovascular disease, time of exercise, troponin T (cTnT), myocarditis

Procedia PDF Downloads 480

Authors: Boutahar Lhoucine, El Bikri Khalid, Benamar Rhali

Abstract:

In this paper, the non-linear free axisymmetric vibration of a thin annular plate made of functionally graded material (FGM) has been studied by using the energy method and a multimode approach. FGM properties vary continuously as well as non-homogeneity through the thickness direction of the plate. The theoretical model is based on the classical plate theory and the Von Kármán geometrical non-linearity assumptions. An approximation has been adopted in the present work consisting of neglecting the in-plane deformation in the formulation. Hamilton’s principle is used to derive the governing equation of motion. The problem is solved by a numerical iterative procedure in order to obtain more accurate results for vibration amplitudes up to 1.5 times the plate thickness. The numerical results are given for the first axisymmetric non-linear mode shape for a wide range of vibration amplitudes and they are presented either in tabular form or in graphical form to show the effect that the vibration amplitude and the variation in material properties have significant effects on the frequencies and the bending stresses in large amplitude vibration of the functionally graded annular plate.

Keywords: non-linear vibrations, annular plates, large amplitudes, functionally graded material

Procedia PDF Downloads 338

Authors: Karima Merchant

Abstract:

The aim of this study was to analyze the impact of the Writing Eight Exercise, an exercise from the Brain Integration Therapy, with Kindergartners who are struggling with writing tasks in school. With the help of this exercise, children were able to cross the midline, an invisible line running from our brain to our feet, which separates the body’s right from left. Crossing the midline integrates the brain hemispheres, thus encouraging bilateral movement. The study was spread over 15 weeks where the children were required to do the Writing Eight Exercise 4 times a week. The data collection methods included observations, student work samples and feedback from teachers and parents. Based on the results of this study, it can be concluded that the Writing Eight Exercise had a positive impact on students’ approach towards writing tasks, letter formation, and fine motor skills.

Keywords: crossing the midline, fine motor skills, letter formation, writing

Procedia PDF Downloads 423

Authors: N. Sena, C. Vasconcelos

Abstract:

Portugal has a lower rate of people who exercise. Fitness centers are a widely recognized context for the performance of an exercise. Thus, the objective of this study is to analyze the motivational factors for the practice of exercise in a sample of Portuguese fitness center users. The sample consists of 34 users (23 men and 11 women), aged between 16 and 60 years old (24.7 ± 11,5 years old). The instrument used for data collection was the Motivation Questionnaire for Exercise (version translated and validated into Portuguese), consisting of forty-nine items grouped into ten motivational factors. Responses to the Exercise Motivation Questionnaire are given on a 6-point Likert scale (0="not at all true for me" to 5="completely true for me"). With regard to the results, it is possible to verify that the motivational factors considered most relevant by the sample of our study were “Well-being” (4.44 ± 0.28), followed by “Health” (4.29 ± 0.57) and “Stress Management” (4.06 ± 0.54). The factors “Affiliation” (3.11 ± 0.49) “Personal Appreciation” (2.26 ± 0.59) and “Medical History” (1.71 ± 0.74) were considered by the respondents to be the least important factors for performing the exercise. The conclusion of this study is that in the sample of this study, the factors that most motivated the practice of exercise were “Well-being”, “Health” and “Stress Management”. In the opposite direction, the factors that least motivated the individuals in this sample to practice exercise were “Affiliation”, “Personal Appreciation” and “Medical History”.

Keywords: exercise, fitness center users, motivational factors, Portugal

Procedia PDF Downloads 55

Authors: Yalcin Kaya, Fatma Arslan, Ahmet Selim Kaya

Abstract:

This study aimed to determine the undesirable hypertrophic anomalies in the body of females and to investigate how they can be affected by the exercise program according to the applied 8 week individual conditions. The research was carried out on 35 women who did not have any regular previous sports practice and had an approximate age of 30 ± 5.0 at the gymnasium because of their asymmetric structure and weight gain of the body. Measurements of width, depth, and periphery were taken from the participants' body, and the exercise protocol was applied for 8 weeks according to the individual measurements in accordance with the obtained measurements. After 8 weeks, the same measurements were applied again. Measurements were made by using ruler and paper tape. The findings were evaluated and differences were analyzed by paired sample t test. According to the findings obtained, ulnae distal proiecturas width averages were 44.77 ± 3.65 and 43.52 ± 3.47 pre- and post-exercise respectively. Bithorachanteric width averages were 29.3 ± 3.12 before exercise and 26.67 ± 3.27 after exercise. Average abdominal widths were observed as 18.64 ± 4.14 (before exercise) and 18.01 ± 6.27 (after exercise). The distances between the malleolus were measured as 16.98 ± 1.62 (before exercise) and 16.70 ± 1.64 (after exercise). The results were statistically significant (p < 0.05). The mean of pre-exercise Externus abdominis circumference was 93.97 ± 8.91, and the mean of post-exercise mean was 90.82 ± 8.24. The results are statistically significant (p < 0.05). In conclusion, findings of the study show that inactivity, daily uncontrolled activities or erroneous postural postures, malnutrition cause some anomalies in the human body. However, with consciously standardized and regular exercises, these abnormalities are reduced by an eight-week exercise protocol in parallel with the expulsion of excess kilos and can be removed when working much longer and fitter, it is proposed to be healthier and more beautiful in appearance.

Keywords: women, body, circumference-width and depth measurements, hypertrophy, exercise

Procedia PDF Downloads 355

Authors: Gennady M. Kulikov, Svetlana V. Plotnikova

Abstract:

This paper focuses on implementation of the sampling surfaces (SaS) method for the three-dimensional (3D) stress analysis of functionally graded (FG) laminated elastic and piezoelectric shells. The SaS formulation is based on choosing inside the nth layer In not equally spaced SaS parallel to the middle surface of the shell in order to introduce the electric potentials and displacements of these surfaces as basic shell variables. Such choice of unknowns permits the presentation of the proposed FG piezoelectric shell formulation in a very compact form. The SaS are located inside each layer at Chebyshev polynomial nodes that improves the convergence of the SaS method significantly. As a result, the SaS formulation can be applied efficiently to 3D solutions for FG piezoelectric laminated shells, which asymptotically approach the exact solutions of piezoelectricity as the number of SaS In goes to infinity.

Keywords: electroelasticity, functionally graded material, laminated piezoelectric shell, sampling surfaces method

Procedia PDF Downloads 658

Authors: Ali Kurşun, Emre Kara, Erhan Çetin, Şafak Aksoy, Ahmet Kesimli

Abstract:

In this study, thermal elastic stress distribution occurred on long hollow cylinders made of functionally graded material (FGM) was analytically defined under thermal, mechanical and thermo mechanical loads. In closed form solutions for elastic stresses and displacements are obtained analytically by using the infinitesimal deformation theory of elasticity. It was assumed that elasticity modulus, thermal expansion coefficient and density of cylinder materials could change in terms of an exponential function as for that Poisson’s ratio was constant. A gradient parameter n is chosen between - 1 and 1. When n equals to zero, the disc becomes isotropic. Circumferential, radial and longitudinal stresses in the FGMs cylinders are depicted in the figures. As a result, the gradient parameters have great effects on the stress systems of FGMs cylinders.

Keywords: functionally graded materials, thermoelasticity, thermomechanical load, hollow cylinder.

Procedia PDF Downloads 429

Authors: Saeid Asghari

Abstract:

The growing interest in sustainability and healthy lifestyles has stimulated the development of solutions that promote mindful consumption and healthier choices. One such solution is the use of transparent graded lanes in product packaging, which enables consumers to visually track their product consumption and encourages portion control. However, the extent to which this packaging affects consumer behavior, trust, and loyalty towards a product or brand, as well as the effectiveness of messaging on the graded lanes, remains unclear. The research aims to examine the impact of transparent graded lanes on consumer behavior, trust, and loyalty towards products or brands in the context of the Janbo chain supermarket in Tehran, Iran, focusing on Ketchup and edible oils containers. A representative sample of 720 respondents is selected using quota sampling based on sex, age, and financial status. The study assesses the effect of messaging on the graded lanes in enhancing consumer recall and recognition of the product at the time of purchase, increasing repeat purchases, and fostering long-term relationships with customers. Furthermore, the potential outcomes of using transparent graded lanes, including the promotion of healthy consumption habits and the reduction of food waste, are also considered. The findings and results can inform the development of effective messaging strategies for graded lanes and suggest ways to enhance consumer engagement with product packaging. Moreover, the study's outcomes can contribute to the broader discourse on sustainable consumption and healthy lifestyles, highlighting the potential role of packaging innovations in promoting these values. We used four theories (social cognitive theory, self-perception theory, nudge theory, and marketing and consumer behavior) to examine the effect of these transparent graded lanes on consumer behavior. The conceptual model integrates the use of transparent graded lanes, consumer behavior, trust and loyalty, messaging, and promotion of healthy consumption habits. The study aims to provide insights into how transparent graded lanes can promote mindful consumption, increase consumer recognition and recall of the product, and foster long-term relationships with customers. Findings suggest that the use of transparent graded lanes on Ketchup and edible oils containers can have a positive impact on consumer behavior, trust, and loyalty towards a product or brand, as well as promote mindful consumption and healthier choices. The messaging on the graded lanes is also found to be effective in promoting recall and recognition of the product at the time of purchase and encouraging repeat purchases. However, the impact of transparent graded lanes may be limited by factors such as cultural norms, personal values, and financial status. Broadly speaking, the investigation provides valuable insights into the potential benefits and challenges of using transparent graded lanes in product packaging, as well as effective strategies for promoting healthy consumption habits and building long-term relationships with customers.

Keywords: packaging customer behavior, purchase, brand loyalty, healthy consumption

Procedia PDF Downloads 223

Authors: Ali Fuad Ashour

Abstract:

Introduction: Contrary to the common belief that physical training for multiple sclerosis (MS) patients might exacerbate fatigue and provoke other symptoms of the illness, it is now widely accepted that exercise can be actually beneficial in terms of activities of daily living, reduced fatigue, and improved quality of life. The aim of this study was to assess the attitude of MS patients toward exercise. Methodology: 112 MS patients who were recruited from the local community participated in this study. We utilised a self-developed questionnaire targeting attitudes and perceptions of MS patients towards physical exercise. The questionnaire was piloted and tested for validity and reliability. Results: Before being diagnosed with MS, 49.9% of our MS patients’ respondents used to engage in different types of physical activities and sports, namely aerobics/walking (35.3%), stretching exercise (18.7%), and strengthening exercise (11.4%). After being diagnosed with MS, 40.8% of our sample showed determination to remain physically active. The interest in sports activities was consistent after the diagnoses with MS and included aerobics/walking (33.8%), stretching exercise (22.6%), and strengthening exercise (19.7%). Discussion: The Kuwaiti respondents thought that lack of encouragement was the main reason for them not exercise. Aptly put, if they try to exercise, they will be discouraged by the loved ones lest the worse happens. On the other side, British patients are generally aware of the benefits of physical and mental health-promoting activities; they can seek help from a wide range of professionals and are more actively involved in the management of their condition. It is therefore important that the benefits of physical activity are promoted among MS patients, and that attitude towards MS and MS patients is changed through education.

Keywords: perception, multiple sclerosis, exercise, physical training

Procedia PDF Downloads 127

Authors: John Gray, Andy Smith, Hazel James

Abstract:

With the introduction of projects such as GP referral and other medical exercise schemes, there has been a shift in the cosmology underpinning exercise leadership. That is, the knowledge base of exercise leaders, specifically personal trainers, has moved from a cosmology based on aesthetic and physical fitness demands to one requiring interaction with the dominant biomedical model underpinning contemporary medicine. In line with this shift research has demonstrated that personal trainer education has aligned itself to a biotechnological model. However, whilst there is a need to examine exercise as medicine, and consider the role of personal trainers as prescribers of these interventions, the possible issues surrounding the growing medicalization of the exercise cosmology have not been explored. Using a phenomenological methodology, and the novel approach of photo-elicitation, this research examined the practices of successful personal trainers. The findings highlight that a growing focus on an iatro-biological based scientific process of exercise prescription may prove problematical. Through the development of a model of practitioner-based knowledge, it is argued there is a possible growing disconnection between the theoretical basis of exercise science and the working cosmology of exercise practitioners.

Keywords: biomedicine, cosmology, personal training, photo-elicitation

Procedia PDF Downloads 343

Authors: Ka'abu Mu'azu

Abstract:

The study examines the effect of varied intensities of aerobic exercise on Systolic Blood Pressure (SBP) among HIV/AIDS positive patients. Participants of mean age of 20.4 years were randomized into four groups. High Intensity Group (HIG), Moderate Intensity Group (MIG), Low Intensity Group (LIG) and Control Group (COG). SBP was measured at baseline (pre-exercise) and post-exercise (8 weeks). Analysis of variance (ANOVA) indicates a significant training effect on resting values of SBP (F [3, 15] = 8.9, P < 0.05). Sheffe post hoc analysis indicated that both HIG and MIG significantly differ from control (P < 0.05). Dependent t- test indicates difference in HIG (t [7] = 6.5, P < 0.05) and slightly in MIG (t [7] = 5.4, P < 0.05). The study concluded that aerobic exercise is effective in reducing resting values of SBP particularly the activities that are high intensity in nature. The study recommends that high and moderate intensity aerobic exercise should be used for improving health condition of HIV/AIDS patients as regard to decrease in resting value of SBP.

Keywords: systolic blood pressure, aerobic exercise, HIV patients, health sciences

Procedia PDF Downloads 355

Authors: B. Nakhostin-Roohi, F. Khoshkhahesh, KH. Parandak, R. Ramazanzadeh

Abstract:

Introduction: The protective effect of antioxidants in diminishing the post-exercise rise of serum CK and LDH in individuals trained for competitive sports has come to light in recent years. This study was conducted to assess the effect of Two-week L-carnitine supplementation on exercise-induced muscle damage, as well as antioxidant capacity after a bout of strenuous exercise in active healthy young men. Methodology: Twenty active healthy men volunteered for this study. Participants were randomized in a double-blind placebo-controlled fashion into two groups: L-carnitine (C group; n = 10) and placebo group (P group; n = 10). The participants took supplementation (2000 mg L-carnitine) or placebo (2000 mg lactose) daily for 2weeks before the main trial. Then, participants ran 14 km. Blood samples were taken before supplementation, before exercise, immediately, 2h and 24h after exercise. Creatine kinase (CK), and lactate dehydrogenase (LDH), and total antioxidant capacity (TAC) were measured. Results: Serum CK and LDH significantly increased after exercise in both groups (p < 0.05). Serum LDH was significantly lower in C group than P group 2h and 24h after exercise (p < 0.05). Furthermore, CK was significantly lower in C group compared with P group just 24h after exercise (p < 0.05). Plasma TAC increased significantly 14 days after supplementation and 24h after exercise in C group compared with P group (p < 0.05). Discussion and conclusion: These results suggest two-week daily oral supplementation of L-carnitine has been able to promote antioxidant capacity before and after exercise and decrease muscle damage markers through possibly inhibition of exercise-induced oxidative stress.

Keywords: L-carnitine, muscle damage, creatine kinase, Lactate dehydrogenase

Procedia PDF Downloads 413

Authors: Mohsen Salesi, Seyyed Zoheir Rabei

Abstract:

Exercise has been considered a cornerstone of diabetes prevention and treatment for decades, but the benefits of resistance training are less clear. The purpose of this study was to determine the impact of resistance training on blood profile and inflammatory marker (CRP) of type 2 diabetes mellitus people. Thirty diabetic male were recruited (age: 50.34±10.28 years) and randomly assigned to 8 weeks resistance exercise training (n=15) and control groups (n=15). Before and after training blood pressure, weight, lipid profile (TC, TG, LDL-c, and HDL-c) and hs-CRP were measured. The resistance exercise training group took part in supervised 50–80 minutes resistance training sessions, three days a week on non-consecutive days for 8 weeks. Each exercise session included approximately 10 min of warm-up and cool-down periods. Results showed that TG significantly decreased (pre 210.19±9.31 vs. 101.12±7.25, p=0.03) and HDL-c significantly increased (pre 42.37±3.15 vs. 47.50±2.19, p=0.01) after exercise training. However, there was no difference between groups in TC, LDL-c, BMI and weight. In addition, a decrease in fasting blood glucose levels showed significant difference between groups (pre 144.65±5.73 vs. 124.21±6.48 p=0.04). Regular resistance exercise training can improve the lipid profile and reducing the cardiovascular risk factors in T2DM patients.

Keywords: lipid profile, resistance exercise, type 2 diabetes mellitus, men

Procedia PDF Downloads 376

Authors: Mohamad Molavi Nojumi, Xiaodong Wang

Abstract:

In this research fracture behaviour of linear elastic isotropic functionally graded materials (FGMs) are investigated using modified finite element method (FEM). FGMs are advantageous because they enhance the bonding strength of two incompatible materials, and reduce the residual stress and thermal stress. Ceramic/metals are a main type of FGMs. Ceramic materials are brittle. So, there is high possibility of crack existence during fabrication or in-service loading. In addition, damage analysis is necessary for a safe and efficient design. FEM is a strong numerical tool for analyzing complicated problems. Thus, FEM is used to investigate the fracture behaviour of FGMs. Here an accurate 9-node biquadratic quadrilateral graded element is proposed in which the influence of the variation of material properties is considered at the element level. The stiffness matrix of graded elements is obtained using the principle of minimum potential energy. The implementation of graded elements prevents the forced sudden jump of material properties in traditional finite elements for modelling FGMs. Numerical results are verified with existing solutions. Different numerical simulations are carried out to model stationary crack problems in nonhomogeneous plates. In these simulations, material variation is supposed to happen in directions perpendicular and parallel to the crack line. Two special linear and exponential functions have been utilized to model the material gradient as they are mostly discussed in literature. Also, various sizes of the crack length are considered. A major difference in the fracture behaviour of FGMs and homogeneous materials is related to the break of material symmetry. For example, when the material gradation direction is normal to the crack line, even under applying the mode I loading there exists coupled modes I and II of fracture which originates from the induced shear in the model. Therefore, the necessity of the proper modelling of the material variation should be considered in capturing the fracture behaviour of FGMs specially, when the material gradient index is high. Fracture properties such as mode I and mode II stress intensity factors (SIFs), energy release rates, and field variables near the crack tip are investigated and compared with results obtained using conventional homogeneous elements. It is revealed that graded elements provide higher accuracy with less effort in comparison with conventional homogeneous elements.

Keywords: finite element, fracture mechanics, functionally graded materials, graded element

Procedia PDF Downloads 149

Authors: A. Selmi

Abstract:

Free vibration analysis of homogenous and axially functionally graded simply supported beams within the context of Euler-Bernoulli beam theory is presented in this paper. The material properties of the beams are assumed to obey the linear law distribution. The effective elastic modulus of the composite was predicted by using the rule of mixture. Here, the complexities which appear in solving differential equation of transverse vibration of composite beams which limit the analytical solution to some special cases are overcome using a relatively new approach called the Differential Transformation Method. This technique is applied for solving differential equation of transverse vibration of axially functionally graded beams. Natural frequencies and corresponding normalized mode shapes are calculated for different Young’s modulus ratios. MATLAB code is designed to solve the transformed differential equation of the beam. Comparison of the present results with the exact solutions proves the effectiveness, the accuracy, the simplicity, and computational stability of the differential transformation method. The effect of the Young’s modulus ratio on the normalized natural frequencies and mode shapes is found to be very important.

Keywords: differential transformation method, functionally graded material, mode shape, natural frequency

Procedia PDF Downloads 274

Authors: Pimporn Thongmuang

Abstract:

The purpose of this research is to study sport and exercise behavior of students in Suan Sunandha Rajabhat University in September of 2012. The sample group used in this research was a group of regular students in undergraduate school enrolled in faculty of science and technology. This sample group consisted of 1,858 students. The research tool used to collect result was the checklist. The data was calculated by statistical percentage. From the research, it was discovered that most students did exercise in previous month. 71.6% of students exercised by running. 61.1% of students exercised in their neighborhood. 60.4% of students exercised in order to keep fit. 60.2% of students agreed that the result from this research can be educational and inspirational for students in campus in terms of living healthily by exercise.

Keywords: exercise behavior, sport behavior, students, health

Procedia PDF Downloads 431

Authors: Dian Ariyawati, Romi Sukoco, Sinung Agung Joko

Abstract:

Background: Postural Orthostatic Tachycardia Syndrome (POTS) is a form of orthostatic intolerance caused by autonomic dysfunction. POTS predominantly occurs in young women. Regular exercise has proven to improve the organ system functions, including autonomous systems. The aim of this research was to determine the correlation between exercise frequency and POTS in young women. Method: 510 young women (16-23 years of age) were screened. They were obtained by interview and physical examination. The diagnosis of POTS was performed with Active Stand Test (AST) and heart rate measurement using a pulsemeter. There were 29 young women who suffered from POTS. The exercise frequency was obtained by interview. Data was statistically analyzed using Spearman Correlation test. Result: The subjects’, who tested positive for POTS didn’t perform regular exercise. The Spearman correlation test showed there was a moderate negative correlation between exercise frequency and POTS in young women (r = -0.487, p < 0.00). Conclusion: There is a moderate reverse correlation between exercise frequency and POTS in young women. Further studies are suggested to develop an exercise program for young who suffered from POTS.

Keywords: POTS, autonomic dysfunction, exercise frequency, young woman

Procedia PDF Downloads 519

Authors: Zhang Jun Xiong

Abstract:

Objective: To explore the effect of physical exercise and outdoor lighting on the improvement of pupils' eyesight. Methods: A total of 208 first grade students in a primary school in Chengdu were enrolled in the study, 104 of whom were nearsighted and 104 had normal vision. They were randomly divided into indoor exercise group, outdoor exercise group, indoor control group and outdoor control group. Indoor and outdoor exercise groups performed moderate and high-intensity aerobic exercise three times a week, 60 minutes each time; The indoor and outdoor control groups had normal study and life during the experiment, without exercise intervention. The experiment lasted for one academic year, and the visual indicators of the subjects were tested before and after the experiment. Results: After the experiment, the visual fatigue index of the subjects with normal vision in the outdoor exercise group, indoor exercise group and outdoor control group decreased by 1.5 ± 2.89, 1.4 ± 3.05, 2.12 ± 2.66 respectively, and the diopter index decreased by 0.30D ± 0.09, 0.41D ± 0.16, 0.40D ± 0.19 respectively, while the visual fatigue score of the subjects with normal vision in the indoor control group increased by 2.3 ± 2.15, and the diopter decreased by 0.53D ± 0.22, There were significant differences in visual fatigue and diopter among the subjects with normal vision in each group (P<0.001). After the experiment, the visual fatigue index of the myopic subjects in the outdoor exercise group, indoor exercise group and outdoor control group decreased by 1.8 ± 1.95, 0.8 ± 1.81, 1.1 ± 1.85 respectively, and the diopter index decreased by 0.35D ± 0.21, 0.52D ± 0.24, 0.52D ± 0.15 respectively, while the visual fatigue score of the myopic subjects in the indoor control group increased by 1.3 ± 2.66, and the diopter decreased by 0.62D ± 0.29. There were significant differences between groups in visual fatigue and diopter (P<0.001). Conclusion: Both physical exercise and outdoor lighting can have a beneficial effect on children's vision, and the superposition effect of the two is better. It is suggested that outdoor physical exercise should be carried out more in primary school.

Keywords: physical exercise, outdoor lighting, pupil, vision, myopia

Procedia PDF Downloads 59

Authors: Esmaeil Bahmyari

Abstract:

The natural frequency analysis of the functionally graded (FG) rotating cylindrical shells subjected to thermal loads is studied based on the three-dimensional elasticity theory. The temperature-dependent assumption of the material properties is graded in the thickness direction, which varies based on the simple power law distribution. The governing equations and the appropriate boundary conditions, which include the effects of initial thermal stresses, are derived employing Hamilton’s principle. The initial thermo-mechanical stresses are obtained by the thermo-elastic equilibrium equation’s solution. As an efficient and accurate numerical tool, the differential quadrature method (DQM) is adopted to solve the thermo-elastic equilibrium equations, free vibration equations and natural frequencies are obtained. The high accuracy of the method is demonstrated by comparison studies with those existing solutions in the literature. Ultimately, the parametric studies are performed to demonstrate the effects of boundary conditions, temperature rise, material graded index, the thickness-to-length and the aspect ratios for the rotating cylindrical shells on the natural frequency.

Keywords: free vibration, DQM, elasticity theory, FG shell, rotating cylindrical shell

Procedia PDF Downloads 54

Authors: Hyun-Ju Oh, Soon-Rim Suh, Mihan Kim

Abstract:

The steady and rapid increase of the older population is a global phenomenon. Chronic diseases and disabilities are increased due to aging. In general, exercise has been known to be most effective in preventing and managing chronic back pain. However, it is hard for the older women to initiate and maintain the exercise. Transtheoretical model (TTM) is one of the theories explain behavioral changes such as exercise. The application of the program considering the stage of behavior change is effective for the elderly woman to start and maintain the exercise. The purpose of this study was to develop TTM based exercise program and to examine its effect for elderly women with chronic back-pain. For the program evaluation, the non-equivalent control pre-posttest design was applied. The independent variable of this study is exercise intervention program. The contents of the program were constructed considering the characteristics of the elderly women with chronic low back pain, focusing on the process of change, the stage of change by the previous studies. The developed exercise program was applied to the elderly women with chronic low back pain in the planning stage and the preparation stage. The subjects were 50 older women over 65 years of age with chronic back-pain who did not practice regular exercise. The experimental group (n=25) received the 8weeks TTM based exercise program. The control group received the book which named low back pain management. Data were collected at three times: before the exercise intervention, right after the intervention, and 4weeks after the intervention. The dependent variables were the processes of change, decisional balance, exercise self-efficacy, back-pain, depression and muscle strength. The results of this study were as follows. Processes of change (<.001), pros of decisional balance (<.001), exercise self-efficacy (<.001), back pain (<.001), depression (<.001), muscle strength (<.001) were higher in the experimental group than in the control group right after the program and 4weeks after the programs. The results of this study show that applying the TTM based exercise program increases the use of the change process, increases the exercise self-efficacy, increases the stage of changing the exercise behavior and strengthens the muscular strength by lowering the degree of pain and depression Respectively. The significance of the study was to confirm the effect of continuous exercise by maintaining regular exercise habits by applying exercise program of the transtheoretical model to the chronic low back pain elderly with exercise intention.

Keywords: chronic back pain, elderly, exercise, women

Procedia PDF Downloads 235

Authors: Arezoo Fallahi

Abstract:

We aimed at investigating the association between health beliefs and exercise behavior in infertile women who were at risk of developing osteoporosis. This cross-sectional study was conducted in Sanandaj city, west of Iran in 2018. From 35 comprehensive healthcare centers, 483 infertile women were included in the study through convenience sampling. Standardized face-to-face interviews were conducted using established, reliable instruments for the assessment of exercise behavior behavior and health beliefs. Logistic regression models were applied to assess the association between exercise behavior and health beliefs. Estimates were adjusted for age, job status, income, literacy, and duration and type of infertility. We reported estimated logits and Odds Ratios (OR) with corresponding 95% confidence intervals (95% CI). Employed women compared to housewives had substantially higher odds of adopting exercise behavior behaviors (OR=3.19, 95% CI=1.53-6.66, p<0.01). Moreover, the odds of exercise behavior adoption increased with self-efficacy (OR=1.35, 95% CI=1.20-1.52, p<0.01), and decreased with perceived barriers (OR=0.90, 95% CI=0.84-0.97, p<0.01). It is essential to increase perceived self-efficacy and reduce perceived barriers to promote EB in infertile women. Consequently, health professionals should develop or adopt appropriate strategies to decrease barriers and increase self-efficacy to enhance exercise behavior in this group of women.

Keywords: infertility, women, exercise, osteoporosis

Procedia PDF Downloads 43

Authors: Ahmed Boujdad

Abstract:

‎ Morocco, a North African nation known for its rich culture and diverse landscapes, is facing evolving challenges related to cardiovascular health and behavioral well-being. Against this backdrop, the paper aims to spotlight the insights emerging from Moroccan research into the impacts of aerobic exercise on cardiovascular physiology and psychological outcomes. Presentations will encompass a range of topics, including exercise-induced adaptations in heart function, blood pressure management, and vascular health specific to the Moroccan population. A notable focus of the paper will be the examination of how aerobic exercise intertwines with Moroccan behavioral patterns and sociocultural factors. The research will delve into the links between regular exercise and its potential to alleviate stress, anxiety, and depression in the Moroccan context. This exploration extends to the role of exercise in bolstering the cultural fabric of Moroccan society, enhancing community engagement, and promoting a sense of well-being.

Keywords: event-related potential‎, executive function, physical activity, kinesiology

Procedia PDF Downloads 49

Authors: Afsaneh Soltani, Zahra Mohajer

Abstract:

Migraine is one of the most common chronic neurological diseases. Migraines affect different aspects of life. Severe migraine headaches lead to dysfunction, a reduced presence at work, and decreased ability to think and make decisions. Non-pharmacological treatments play a very important role in controlling and preventing migraine headaches. A healthy lifestyle helps control migraine headaches. Migraine headaches can be reduced by following these steps: Avoiding stress, eating regularly and avoiding hunger and thirst, avoiding stimulants such as chocolate, caffeine, and cigarettes, following a regular bedtime routine, or avoiding sleep deprivation. Exercise a lot, and do regular exercise (and prevent obesity). Non-pharmacological treatment is especially important in pregnant women and children because in these cases, medical treatments are not preferred due to the many side effects. Exercise is one of the most effective and uncomplicated non-pharmacological alternatives in the treatment of migraine headaches. Exercising for episodic migraines is a safe, effective, and promising complementary treatment option. Numerous studies have shown that aerobic exercise reduces the severity and duration of migraine headaches. Effective aerobic exercise includes cycling and brisk walking. Exercise improves the quality of life and reduces the use of medication in people with migraines. Patients who exercise have fewer migraine days, resulting in better personal, social, and occupational performance. Several studies have shown that pain intensity and frequency in patients who exercise regularly decreased significantly after exercise compared to controls who did not exercise. According to a study, regular exercise reduces the levels of interleukins, especially IL-12P70, which reduces anxiety and reduces the number of days of migraine in patients. An article has shown that endurance exercise reduces the number of migraine days and also increases cerebrovascular health in migraine patients. According to studies, the minimum duration of exercise to achieve a positive effect of exercise in patients with migraine is 3 months (12 weeks) and 40 minutes three times a week.

Keywords: exercise, headache, migraine, physical activity

Procedia PDF Downloads 82

Authors: Abbas Nasir, Xiong Zhang, Sohail Ahmad, Yiping Cui

Abstract:

Non-polar a-plane AlGaN epilayers of high structural quality have been grown on r-sapphire substrate by using metalorganic chemical vapor deposition (MOCVD). A graded non-polar AlGaN buffer layer with variable aluminium concentration was used to improve the structural quality of the non-polar a-plane AlGaN epilayer. The characterisations were carried out by high-resolution X-ray diffraction (HR-XRD), atomic force microscopy (AFM) and Hall effect measurement. The XRD and AFM results demonstrate that the Al-composition-graded non-polar AlGaN buffer layer significantly improved the crystalline quality and the surface morphology of the top layer. A low root mean square roughness 1.52 nm is obtained from AFM, and relatively low background carrier concentration down to 3.9×  cm^-3 is obtained from Hall effect measurement.

Keywords: non-polar AlGaN epilayer, Al composition-graded AlGaN layer, root mean square, background carrier concentration

Procedia PDF Downloads 112

Authors: Chun-Chin Huang

Abstract:

Individuals with prediabetes increase the risk of developing type 2 diabetes. Exercise is a potent stimulator of skeletal muscle glucose uptake and thus good for maintaining glucose homeostasis. That could be a conducive method to improve blood glucose regulation and prevent type 2 diabetes without medication intake. The aim of this study was to summarize mechanisms of insulin resistance and investigate the beneficial effects of acute and chronic aerobic exercise on glycemic control in prediabetes and type 2 diabetes. Aerobic exercise regulates glucose homeostasis and reduces blood glucose, insulin concentrations. Therefore, the type of aerobic exercise brings positive effects to prediabetes and type 2 diabetes.

Keywords: insulin resistance, glucose sensitivity, impaired fasting glucose, impaired glucose tolerance

Procedia PDF Downloads 127