Effect of resistance training with different frequencies and subsequent detraining on muscle mass and appendicular lean soft tissue,IGF-1, and testosterone in older women     

Matheus Amarante Do Nascimento  Aline Mendes Gerage  Danilo Rodrigues Pereira Da Silva  Alex Silva Ribeiro  Daniel Gomes Da Silva Machado  Fábio Luiz Cheche Pina 《European Journal of Sport Science》2019,19(2):199-207

Objective: To analyse the effect of resistance training (RT) frequency on muscle mass, appendicular lean soft tissue, insulin-like growth factor 1 (IGF-1), testosterone, and their changes with detraining in older women. Methods: Forty-five physically independent older women (≥ 60?years) were randomly assigned to perform RT either two (G2X, n = 21) or three times/week (G3X, n = 24), during 12?weeks (8 exercises, 1 set of 10–15 repetition maximum). Muscle mass and appendicular lean soft tissue, IGF-1, testosterone, and dietary intake were measured at pre-training, post-training, and after detraining (12?weeks). Results: Muscle mass and appendicular lean soft tissue significantly increased post-training (G2X?=?+5.5% and G3X?=?+5.8%, P?P?P?Conclusion: We conclude that lower RT frequency is as effective as higher frequency to improve muscle mass and appendicular lean soft tissue, and to maintain testosterone and IGF-1. Additionally, detraining may reduce testosterone regardless of RT frequency. These results are specifically for community-dwelling older women and may not be generalized to other populations.  相似文献   

Upper limb and trunk muscle activity patterns during seated and standing cycling     

Nicolas A. Turpin  Antony Costes  Pierre Moretto  Bruno Watier 《Journal of sports sciences》2017,35(6):557-564

The objective of this study is to clarify the functional roles of upper limb muscles during standing and seated cycling when power output increases. We investigated the activity of seven upper limb and trunk muscles using surface electromyography (EMG). Power outputs ranged from ~100–700 W with a pedalling frequency of 90 revolution per minute. Three-dimensional handle and pedal forces were simultaneously recorded. Using non-negative matrix factorisation, we extracted muscle synergies and we analysed the integrated EMG and EMG temporal patterns. Most of the muscles showed tonic activity that became more phasic as power output increased. Three muscle synergies were identified, associated with (i) torso stabilisation, (ii) compensation/generation of trunk accelerations and (iii) upper body weight support. Synergies were similar for seated and standing positions (Pearson’s r > 0.7), but synergy #2 (biceps brachii, deltoidus and brachioradialis) was shifted forward during the cycle (~7% of cycle). The activity levels of synergy #1 (latissimus dorsi and erector spinae) and synergy #2 increased markedly above ~500 W (i.e., ~+40–70% and +130–190%) and during periods corresponding to ipsi- and contralateral downstrokes, respectively. Our study results suggest that the upper limb and trunk muscles may play important roles in cycling when high power outputs are required.  相似文献   

Overall indexes of coordination in front crawl swimming     

Bruno Mezêncio  João Pedro Pinho  Rudolf Huebner  João Paulo Vilas-Boas  Alberto Carlos Amadio  Julio Cerca Serrão 《Journal of sports sciences》2020,38(8):910-917

ABSTRACT

The aim of this study was to propose a group of parameters able to quantify not only arm coordination but also inter limb coordination. These include the well know index of coordination with the relative duration of the stroke phases and two new parameters: the Index of synchronization (Ids) between arms and legs actions; and the Index of inter limb coordination (IdIC) calculated as the relative foot position during successive arm stroke phases. These parameters were compared between experts and amateur swimmers in a maximal front crawl sprint. The influence of arm stroke in leg kick parameters was also assessed, comparing the full stroke condition with a condition without arms actions. Sixty-five per cent of expert swimmers used synchronized limb actions while 95% of amateur swimmers used non-synchronized limb motions. These synchronized expert swimmers also converged towards a specific coordination pattern between foot position and arm stroke phases. In the condition without arms, both groups changed kick rate and amplitude. The present study reveals the interdependency of arms and legs actions and the importance of coordination and synchronization between limbs. Therefore, the proposed group of overall indexes of coordination provides a more complete marker for the analysis of swimming technique.  相似文献   

Sibling Pretend Play in Early and Middle Childhood: The Role of Creativity and Maternal Context     

Nina Howe  Andrea Bruno 《Early education and development》2013,24(6):940-962

  相似文献   

Ivan Illich's Late Critique of Deschooling Society: “I Was Largely Barking Up the Wrong Tree”     

Rosa Bruno‐Jofré  Jon Igelmo Zaldívar 《Educational theory》2012,62(5):573-592

In this article, Rosa Bruno‐Jofré and Jon Igelmo Zaldívar examine Ivan Illich's own critique of Deschooling Society, and his subsequent revised critique of educational institutions and understanding of education, within the context of both his personal intellectual journey and the general epistemological shift that started to take shape in the early 1980s. Bruno‐Jofré and Zaldívar consider how, over time, Illich refocused his quest on examining the roots (origin) of modern certitudes (such as those related to education) and explored how human beings are integrated into the systems generated by those “certainties.” Illich engaged himself in historical analysis rather than providing responses to specific contemporary problems, while maintaining an interest in the relation between the present and the past. Under the metaphors of the word, the page, and the screen, he identified three great mutations in Western social imaginaries and the reconstruction of the individual self. Bruno‐Jofré and Zaldívar argue that while his written work, including Deschooling Society, generally had an apophatic character, his critique of education, particularly in the late 1980s and 1990s, is intertwined with his analysis of the parable of the Good Samaritan and his belief that modernity is an outcome of corrupted Christianity.  相似文献   

农村学校撤并对学生上学距离的影响——基于GIS和Ordinal Logit模型的分析   总被引：1，自引：0，他引：1  

赵丹  吴宏超  Bruno Parolin 《教育学报》2012,(3):62-73

农村义务教育学校布局调整是以撤并小规模学校为主要手段,旨在促进教育资源均衡配置的一项重大教育政策。通过广东省某山区县2003—2009年的学校布局规划数据,从物理距离、时间距离和文化距离的分类视角,运用GIS技术和Ordinal Logit模型分析农村学校撤并对学生上学距离产生的直接影响。研究结果表明:撤并农村学校导致学生上学的物理距离和时间距离增加,偏远学生上学难问题凸显;对学生的文化距离同样产生显著的负面影响。在未来学校布局调整的进程中,县域教育决策者应将关注点从一味追求规模效益转移到教育公平和教育质量上来。要保证农村学生就近入学,设定上学距离的限制;促进学校间教育资源的均衡配置,保证所有学生享受同等质量的教育资源;采用科学的规划程序完善布局调整政策的实施。  相似文献   

International trends in health science librarianship: Part 2--Northern Europe     

Dollfuss H  Bauer B  Declève G  Verhaaren H  Utard-Wlerick G  Bakker S  Leclerq E  Murphy J 《Health information and libraries journal》2012,29(2):166-171

This is the third in a series of articles exploring international trends in health science librarianship in the first decade of the 21st century. The invited authors were asked to reflect on developments in their country--viz. Austria, Belgium, France and the Netherlands. Future issues will track trends in the Nordic countries, Southern Europe and Latin America. JM.  相似文献   

PART III: KINANTHROPOMETRY     

Ricardo Dantas de Lucas  Fabrizio Caputo  Kristopher Mendes de Souza  AndrÉ Roberto Sigwalt  Karina Ghisoni  Paulo Cesar Lock Silveira 《Journal of sports sciences》2013,31(1):22-27

Whole-body bone mineral density and bone mineral mass in young adult rugby union players.  相似文献   

Effects of replica running shoes upon external forces and muscle activity during running     

Ana Paula Da Silva Azevedo  Kátia Brandina  Roberto Bianco  Vitor Henrique De Oliveira  Juliana Roque De Souza  Bruno Mezencio 《Journal of sports sciences》2013,31(9):929-935

Abstract

Twelve participants ran (9 km · h^?1) to test two types of running shoes: replica and original shoes. Ground reaction force, plantar pressure and electromyographic activity were recorded. The shoes were tested randomly and on different days. Comparisons between the two experimental conditions were made by analysis of variance (ANOVA) test (P ≤ 0.05). The time to first peak, loading rate of the first peak and impulse of the first 75 ms of stance were significantly different between the shoes (P ≤ 0.05), revealing an increase of impact forces for the replica shoes. The peak plantar pressure values were significantly higher (P ≤ 0.05) when wearing replica shoes. During running, the contact area was significantly smaller (P ≤ 0.05) for the replica shoe. The electromyographic activity of the analysed muscles did not show changes between the two shoes in running. These findings suggest that the use of replica running shoes can increase the external load applied to the human body, but may not change the muscle activity pattern during locomotion. This new mechanical situation may increase the risk of injuries in these movements.  相似文献   

Validity and reliability of a 6-a-side small-sided game as an indicator of match-related physical performance in elite youth Brazilian soccer players     

Rodrigo Aquino  Bruno Melli-Neto  João Victor S. Ferrari  Bruno L. S. Bedo  Luiz H. Palucci Vieira  Paulo Roberto P. Santiago 《Journal of sports sciences》2013,31(23):2639-2644

ABSTRACT

The aims of this study were: (i) to compare the external and internal load during a 6-a-side small-sided game (6v6-SSG) according to age-group; (ii) to relate these parameters between the 6v6-SSG and official matches; and (iii) to test the reliability of the 6v6-SSG. A total of 51 Brazilian youth soccer players participated in this study (U11 [n = 16]; U13 [n = 10]; U15 [n = 9]; U17 [n = 8]; U20 [n = 8]). Three experiments were conducted. Experiment A: fifty-one U11 to U20 players were submitted to 6v6-SSGs (n = 10 games; two for each age-group). Experiment B: thirty-two players were randomized to also play official matches (n = 6 matches). Experiment C: thirty-five youth players played the 6v6-SSG twice for test and retest reliability analysis. External load was obtained using Global Positioning Systems and the internal load parameter was calculated through mean heart rate. Statistical approaches showed progressive increases in all parameters according to categories (U11< U13< U15< U17< U20; p < 0.05; ES = 0.42?23.68). Even controlling for chronological age, all parameters showed likely to almost certain correlations between 6v6-SSG and official matches (r = 0.25?0.92). Collectively, the proposed protocol indicates good reliability (CV% = 2.0?12.6; TE% = 2.3?2.7%; ICC = 0.78?0.90). This research suggests that the 6v6-SSG is an alternative tool to indicate match-related physical performance in youth soccer players.  相似文献