60 research outputs found

    HAMSTRINGS COACTIVATION IN TRAINED LONG JUMPERS AND UNTRAINED INDIVIDUALS DURING DROP JUMPING

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    The purpose of this study was to examine the EMG activity patterns of the hamstrings during drop jumping from different heights in trained longer jumpers and controls. A group of trained long jumpers and a group of untrained subjects performed maximal drop jumps from 20cm, 40cm and 60 cm on a force platform. The surface EMG activity of the hamstrings was recorded using bipolar electrodes. The ground reaction forces (GRF) and 3-D kinematic data were also recorded. Two-way analysis of variance tests indicated non-significant differences in hamstring EMG amplitude between trained and untrained athletes. However, the long jumpers had significantly higher vertical GRF values and some kinematic differences compared to untrained individuals. The absence of higher hamstrings activity in the long jumpers may have been a contributing factor in their higher performance compared to controls. However, the same result indicates that this increased performance may be accompanied by a possible increased risk of knee joint instability

    Role of Religion in Shaping Ethical and Moral Values Among the Youths in Athens, Greece

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    Religion can be understood as a system of beliefs, practices, and values that relate to the nature of existence and the universe, and that often involve a belief in one or more supernatural or divine entities. Different religions have different beliefs, practices, and values, and there is often significant diversity within a particular religion as well. Many religions provide a set of moral and ethical principles that guide behavior and decision-making, helping individuals to navigate complex ethical issues and make choices that align with their values. Ethical and moral values are principles or beliefs that guide behavior and decision-making. Moral values are important for individuals to live in harmony with others and to make ethical choices. Moral values among youths are shaped by a variety of factors, including family, education, religion, and culture. It was discovered that young people who are actively involved in religious communities are more likely to exhibit prosocial behavior, such as volunteerism, empathy, and moral reasoning, than those who are not involved in religious communities. Religion provides a supportive and nurturing environment for young people, and offers guidance and support as they navigate complex ethical and moral issues. The study concluded that religion plays a significant role in shaping human history and culture, influencing art, literature, music, and philosophy, and contributing to the development of social and political institutions. The study recommended that religious institutions should strive to create welcoming and inclusive environments that foster a sense of community and belonging among young people. Religious leaders should engage with young people and encourage them to develop their own moral compass. Religious institutions should also collaborate with parents and educators to promote positive values and ethical behavior among young people

    Role of Religion in Shaping Ethical and Moral Values Among the Youths in Athens, Greece

    Get PDF
    Religion can be understood as a system of beliefs, practices, and values that relate to the nature of existence and the universe, and that often involve a belief in one or more supernatural or divine entities. Different religions have different beliefs, practices, and values, and there is often significant diversity within a particular religion as well. Many religions provide a set of moral and ethical principles that guide behavior and decision-making, helping individuals to navigate complex ethical issues and make choices that align with their values. Ethical and moral values are principles or beliefs that guide behavior and decision-making. Moral values are important for individuals to live in harmony with others and to make ethical choices. Moral values among youths are shaped by a variety of factors, including family, education, religion, and culture. It was discovered that young people who are actively involved in religious communities are more likely to exhibit prosocial behavior, such as volunteerism, empathy, and moral reasoning, than those who are not involved in religious communities. Religion provides a supportive and nurturing environment for young people, and offers guidance and support as they navigate complex ethical and moral issues. The study concluded that religion plays a significant role in shaping human history and culture, influencing art, literature, music, and philosophy, and contributing to the development of social and political institutions. The study recommended that religious institutions should strive to create welcoming and inclusive environments that foster a sense of community and belonging among young people. Religious leaders should engage with young people and encourage them to develop their own moral compass. Religious institutions should also collaborate with parents and educators to promote positive values and ethical behavior among young people

    "hCG priming" effect in controlled ovarian stimulation through a long protocol

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    <p>Abstract</p> <p>Background</p> <p>Recently, it has been demonstrated that, in patients down-regulated by GnRH analogues (GnRHa), a short-term pre-treatment with recombinant LH (rLH), prior to recombinant FSH (rFSH) administration, increases the number of small antral follicle prior to FSH stimulation and the yield of normally fertilized embryos. However, no data exist in the literature regarding the potential beneficial effect of "hCG priming" in controlled ovarian hyperstimulation (COH) through a long GnRH-a protocol, which binds the same receptor (LH/hCGR), though it is a much more potent compared to LH. The primary aims of this study were to assess the effect of short-term pre-rFSH administration of hCG in women entering an ICSI treatment cycle on follicular development, quality of oocytes and early embryo development. The secondary endpoints were to record the effects on endometrial quality and pregnancy rate.</p> <p>Methods</p> <p>Patients with a history of at least one previous unsuccessful ICSI cycle were randomly assigned into two groups to receive treatment with either a long protocol with rFSH (control group) or a long protocol with rFSH and pre-treatment with hCG (hCG group). In particular, in the latter group, a fixed 7 days course of 200 IU/day hCG was administered as soon as pituitary desensitization was confirmed.</p> <p>Results</p> <p>The mean number of oocytes retrieved was not significantly different between the two treatment groups, although the percentage of mature oocytes tended to be higher but not significantly different in hCG-treated patients. The percentage of patients with more than one grade 3 embryos was higher in the pre-treatment group, which also showed a higher pregnancy rate.</p> <p>Conclusion</p> <p>All the above clinical observations, in conjunction with previous data, suggest a point towards a beneficial "hCG priming" effect in controlled ovarian hyperstimulation through a long GnRH-a down-regulation protocol, particularly in patients with previous ART failures.</p

    The acquisition of pronouns by French children: A parallel study of production and comprehension

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    This study examines syntactic and morphological aspects of the production and comprehension of pronouns by 99 typically developing French-speaking children aged 3 years, 5 months to 6 years, 5 months. A fine structural analysis of subject, object, and reflexive clitics suggests that whereas the object clitic chain crosses the subject chain, the reflexive clitic chain is nested within it. We argue that this structural difference introduces differences in processing complexity, chain crossing being more complex than nesting. In support of this analysis, both production and comprehension experiments show that children have more difficulty with object than with reflexive clitics (with more omissions in production and more erroneous judgments in sentences involving Principle B in comprehension). Concerning the morphological aspect, French subject and object pronouns agree in gender with their referent. We report serious difficulties with pronoun gender both in production and comprehension in children around the age of 4 (with nearly 30% errors in production and chance level judgments in comprehension), which tend to disappear by age 6. The distribution of errors further suggests that the masculine gender is processed as the default value. These findings provide further insights into the relationship between comprehension and production in the acquisition proces

    The Effect of Body Mass on the Shoe-Athlete Interaction

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    Long-distance running is known to induce joint overloading and elevate cytokine levels, which are the hallmarks for a variety of running-related injuries. To address this, footwear systems incorporate cushioning midsoles to mitigate injurious mechanical loading. The aim of this study was to evaluate the effect of athlete body mass on the cushioning capacity of technical footwear. An artificial heel was prototyped to fit the impact pattern of a heel-strike runner and used to measure shock attenuation by an automated drop test. Impact mass and velocity were modulated to simulate runners of various body mass and speeds. The investigation provided refined insight on running-induced impact transmission to the human body. The examined midsole system was optimized around anthropometric data corresponding to an average (normal) body mass. The results suggest that although modern footwear is capable of attenuating the shock waves occurring during foot strike, improper shoe selection could expose an athlete to high levels of peak stress that could provoke an abnormal cartilage response. The selection of a weight-specific cushioning system could provide optimum protection and could thus prolong the duration of physical exercise beneficial to maintaining a simulated immune system

    Comparison of Joint Work During Load Absorption Between Weightlifting Derivatives

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    Suchomel, TJ, Giordanelli, MD, Geiser, CF, and Kipp, K. Comparison of joint work during load absorption between weightlifting derivatives. J Strength Cond Res 35(2S): S127–S135, 2021—This study examined the lower-extremity joint-level load absorption characteristics of the hang power clean (HPC) and jump shrug (JS). Eleven Division I male lacrosse players were fitted with 3-dimensional reflective markers and performed 3 repetitions each of the HPC and JS at 30, 50, and 70% of their 1 repetition maximum (1RM) HPC while standing on force plates. Load absorption joint work and duration at the hip, knee, and ankle joints were compared using 3-way repeated-measures mixed analyses of variance. Cohen\u27s d effect sizes were used to provide a measure of practical significance. The JS was characterized by greater load absorption joint work compared with the HPC performed at the hip (p \u3c 0.001, d = 0.84), knee (p \u3c 0.001, d = 1.85), and ankle joints (p \u3c 0.001, d = 1.49). In addition, greater joint work was performed during the JS compared with the HPC performed at 30% (p \u3c 0.001, d = 0.89), 50% (p \u3c 0.001, d = 0.74), and 70% 1RM HPC (p \u3c 0.001, d = 0.66). The JS had a longer loading duration compared with the HPC at the hip (p \u3c 0.001, d = 0.94), knee (p = 0.001, d = 0.89), and ankle joints (p \u3c 0.001, d = 0.99). In addition, the JS had a longer loading duration compared with the HPC performed at 30% (p \u3c 0.001, d = 0.83), 50% (p \u3c 0.001, d = 0.79), and 70% 1RM HPC (p \u3c 0.001, d = 0.85). The JS required greater hip, knee, and ankle joint work on landing compared with the load absorption phase of the HPC, regardless of load. The HPC and JS possess unique load absorption characteristics; however, both exercises should be implemented based on the goals of each training phase

    A comparison of catch phase force-time characteristics during clean derivatives from the knee

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    The aim of this study was to compare load-absorption force-time characteristics of the clean from the knee (CK), power clean from the knee (PCK) and clean pull from the knee (CPK). Ten collegiate athletes (age 27.5 ± 4.2 years; height 180.4 ± 6.7 cm; mass 84.4 ± 7.8 kg), performed three repetitions each of the CK, PCK and CPK with 90% of their 1RM power clean on a force platform. The CK load-absorption duration (0.95 ± 0.35 s) was significantly longer compared to the CPK (0.44 ± 0.15 s; p 0.05, d = 1.08), with no differences between PCK and CPK (p > 0.05, d = 0.91). The CPK demonstrated the greatest mean force (2039 ± 394 N), which was significantly greater than the PCK (1771 ± 325 N; p = 0.012, d = 0.83), but not significantly different to the CK (1830 ± 331 N; p > 0.05, d = 0.60); CK and PCK were not different (p > 0.05, d = 0.18). Significantly more load-absorption work was performed during the CK (655 ± 276 J) compared to the PCK (288 ± 109 J; d = 1.75, p 0.05). Additionally, more load-absorption work was performed during the CPK compared to the PCK (d = 1.90, p = 0.032). Inclusion of the catch phase during the CK does not provide any additional stimulus in terms of mean force or work during the load-absorption phase compared to the CPK, while the CPK may be beneficial in training rapid force absorption due to high force and a short duration

    Early hCG addition to rFSH for ovarian stimulation in IVF provides better results and the cDNA copies of the hCG receptor may be an indicator of successful stimulation

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    A simple, safe and cost-effective treatment protocol in ovarian stimulation is of great importance in IVF practice, especially in the case of previous unsuccessful attempts. hCG has been used as a substitute of LH because of the degree of homology between the two hormones. The main aim of this prospective randomized study was to determine, for the first time, whether low dose hCG added to rFSH for ovarian stimulation could produce better results compared to the addition of rLH in women entering IVF-ET, especially in those women that had previous IVF failures. An additional aim was to find an indicator that would allow us to follow-up ovarian stimulation and, possibly, modify it in order to achieve a better IVF outcome; and that indicator may be the cDNA copies of the LH/hCG receptor. Group A patients (n = 58) were administered hCG and Group B rLH (n = 56) in addition to rFSH in the first days of ovarian stimulation. The number of follicles and oocytes and, most importantly, implantation and pregnancy rates were shown to be statistically significantly higher in the hCG group. This study has also determined, for the first time to our best knowledge, m-RNA for LH/hCG receptors in the lymphocytes of peripheral blood 40 h before ovum pick-up. cDNA levels of the hCG receptor after ovarian stimulation were significantly higher among women receiving hCG compared to those receiving LH. In addition, higher levels were encountered among women with pregnancy compared to those without, although this was not statistically significant due to the small number of pregnancies. It seems that hCG permits a highly effective and more stable occupancy of rLH/hCG receptors and gives more follicles and more oocytes. The determination of cDNA copies could be, in the future, a marker during ovulation induction protocols and of course a predictor for the outcome of ART in the special subgroup of patients with previous failures

    Variable, but not free-weight, resistance back squat exercise potentiates jump performance following a comprehensive task-specific warm-up

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    Studies examining acute, high-speed movement performance enhancement following intense muscular contractions (frequently called "post-activation potentiation"; PAP) often impose a limited warm-up, compromizing external validity. In the present study, the effects on countermovement vertical jump (CMJ) performance of back squat exercises performed with or without elastic bands during warm-up were compared. After familiarization, fifteen active men visited the laboratory on two occasions under randomized, counterbalanced experimental squat warm-up conditions: (a) free-weight resistance (FWR) and (b) variable resistance (VR). After completing a comprehensive task-specific warm-up, three maximal CMJs were performed followed by three back squat repetitions completed at 85% of 1-RM using either FWR or VR Three CMJs were then performed 30 seconds, 4 minutes, 8 minutes, and 12 minutes later. During CMJ trials, hip, knee, and ankle joint kinematics, ground reaction force data and vastus medialis, vastus lateralis, and gluteus maximus electromyograms (EMG) were recorded simultaneously using 3D motion analysis, force platform, and EMG techniques, respectively. No change in any variable occurred after FWR (P > 0.05). Significant increases (P < 0.05) were detected at all time points following VR in CMJ height (5.3%-6.5%), peak power (4.4%-5.9%), rate of force development (12.9%-19.1%), peak concentric knee angular velocity (3.1%-4.1%), and mean concentric vastus lateralis EMG activity (27.5%-33.4%). The lack of effect of the free-weight conditioning contractions suggests that the comprehensive task-specific warm-up routine mitigated any further performance augmentation. However, the improved CMJ performance following the use of elastic bands is indicative that specific alterations in force-time properties of warm-up exercises may further improve performance
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