Staphylococcus aureus est l’un des principaux agents étiologiques des infections suppuratives superficielles et profondes ainsi que des syndromes liés à l’action de toxines. Paradoxalement, cette bactérie est un agent commensal qui est présent sur la peau ainsi que dans les cavités nasales notamment. Cela permet de considérer cette bactérie comme un organisme colonisant commensale. Les bases génétiques expliquant la différence entre une bactérie pathogène et une bactérie commensale reste inconnues. En utilisant la technique Optical Maps sur des souches de S. aureus isolées de plaies de pieds diabétiques avec différents niveau de virulence, nous avons pu montrer l’existence d’un prophage insérés dans le génome des souches colonisantes et absent des souches infectantes. Le phage, nommé ROSA, est localisé dans un hotspot d’insertion de phage NM2. Il est aussi localisé en amont du locus isd qui est requis pour l’assimilation du fer essentiel à la bactérie dans sa phase pathogène. Le phage ROSA inactive la voie isd en dérégulant l’activité du régulateur transcriptionnel majeur Fur en absence de fer. Il réduit aussi la virulence de ces souches sur les 2 modèles de virulence (Le ver C. elegans et le Zebrafish). L’expulsion du phage ROSA restaure la régulation du locus isd par Fur et la production de sidérophores en absence de Fer, la formation du biofilm et la virulence des souches. La mutation du gène Fur nous a permis de déduire que le phage ROSA affectait les bactéries de manière indépendante de Fur. Enfin, nous avons étudié la prévalence des souches colonisantes sur les plaies de pieds diabétiques. Nous avons observé que 20% des souches présentait l’insertion ROSA et 89% appartenait au complexe clonal CC8. Les souches colonisantes, avec leur niveau bas de virulence, devraient faire l’objet de détection dans le but de rationnaliser l’utilisation des antibiotiques et ainsi lutter contre l’apparition de bactéries multirésistantes aux antibiotiques. / Staphylococcus aureus is an opportunistic bacterium capable of causing a wide range of severe diseases when it gains access to underlying tissues. Paradoxically, this causative pathogen is a common inhabitant of the skin microflora and colonizes the nares and other human mucosa, and as such, may be considered as a commensal colonizing organism. The genetic basis for the differences in pathogenic/colonizing potential is unknown. By performing optical maps comparisons of a collection of S. aureus strains of defined virulence potential isolated from diabetic foot ulcers at different stages, we brought to light a prophage present in colonizing-causing bacteria. The phage, namely ROSA, was localized in a hotspot region NM2 near the locus isd, the main iron surface determinant that transport iron across the bacterial wall. It induces a deregulation of the activity of the transcriptional regulator Fur involving the biofilm formation of the bacteria in response to low iron environment. It reduced also significantly the virulence of the strain in two in vivo models (the nematode C. elegans and the zebrafish). The expulsion of the phage restored the regulation of the locus isd, the siderophore production, the biofilm formation and the virulence of the strain. The mutation of the fur gene within the colonizing strain enabled us to determine that the phage ROSA affect the the bacteria in a Fur-independent manner. Finally we determined the prevalence of these colonizing strains in skin and soft tissue infections (diabetic foot ulcers). We observed that 20% (39/195) of the strains harboured this insertion and 89% belonged to the clonal complex CC8. This colonizing strain by its low virulence potential must be detected in the aim to contribute to a sounder use of antibiotic treatment, an important point in front of the increase of multidrug resistant bacteria.

Il ressort fréquemment des discours d’acteurs qu’une rencontre sportive n’est jamais gagnée d’avance et que partant, il n’y a pas, ou plus, de petites équipes, les adversaires étant toujours à « prendre au sérieux ». Si le football était un joueur de son propre sport, il ne dérogerait pas à ces aphorismes. Il l’aurait pu quand, accompagnant les débuts de la mondialisation, il marquait de son empreinte la géographie mondiale et nationale des foot-ball et dominait ses concurrents en termes de possession de l’espace. Mais le champ sportif s’est aujourd’hui diversifié en raison de la pluralité de ses pratiques comme celle de leurs modes d’organisation, et il lui apporte de nouveaux opposants ou renforce ses « vieux » challengeurs. De ce fait, un nouveau match a commencé, dont la géographie s’est emparée pour le commenter à sa main : c’est elle qui décide du résultat final, par ses concepts, ses méthodes et ses outils. La comparaison des diffusions, des logiques de localisation et des stratégies géomarketing du football, du futsal, du beach soccer et du football indoor se mue de la sorte en autant d’actions, d’occasions, de phases de jeu qui animent la rencontre de ces cultures sportives « balle au pied ». Celles-ci ne se jouent pas partout, ni au même endroit : leurs terrains ne se confondent pas. Et c’est à l’échelle urbaine que la tension de ce match atteint son paroxysme. Avec l’agglomération lilloise pour toile de fond, cette étude témoignera ainsi de l’implantation différenciée, hiérarchisée et segmentée des foot-ball dans l’espace géographique. / There are some lessons that can be taken out from discussions between a football game participants: no game is a sure thing, there are no small teams anymore, and you can’t underestimate the value of your opponents. If football was a player, he wouldn’t dismiss these aphorisms. Not anymore, because the time has passed when it could rely on its supremacy to turn away from these truths. As a pioneering sport, football has moved along with the early stages of globalisation and has heavily influenced the geography of worldwide and national football codes today: in terms of possession, football reigns over its competitors. However, the diversity of the field of sports, impacted by the variety of its activities and their organisations brings new contenders or strengthen its former challengers. In this way, geography finds an easy subject to discuss. With its concepts, methods and tools, geography decides on the final result. This contest is heightened by actions, big chances or plays which turned into expansion, location and geomarketing strategy of football, futsal, beach soccer and five-a-side football. These sporting cultures don’t play everywhere, neither do they play in the same place: their fields don’t collide. On a smaller scale, that of a city, the game’s tension reaches its climax. Focussed on metropolitan Lille, this study will support differentiated, ranked and segmented football codes in geographic space.

Le diabète sucré est un problème majeur de santé publique. L’une de ses principales complications est l’ulcère du pied (UPD) à l’origine d’infections et de nombreuses amputations. Ces plaies sont majoritairement polymicrobiennes. La principale bactérie isolée est Staphylococcus aureus (SA) qui pose d’importants problèmes en thérapie courante. Bactérie commensale notamment des fosses nasales, elle est un vrai pathogène au niveau des UPD. La compréhension du passage du commensalisme à la pathogénicité reste peu connue. Or récemment une souche colonisante de SA présentant un faible potentiel de virulence, et isolée sur un UPD a été identifiée. Cette souche présente un phage (ROSA-like) inséré dans son génome dont la stabilité a été démontrée. Ce phage est responsable de la faible virulence de cet isolat. Ce travail de doctorat a permis : i) de mettre en évidence l’implication du phage ROSA-like dans la dérégulation des mécanismes d’acquisition du fer, mécanismes essentiels pour la survie du SA ainsi que dans le métabolisme global de cette souche. Ces résultats ont confirmé le rôle clé du phage dans la baisse de la virulence du SA colonisant ; ii) à partir d’un modèle in vitro d’infections chroniques mimant les conditions rencontrées dans les UPD, d’étudier le comportement de souches cliniques de SA (colonisantes/infectantes) en fonction des différentes conditions environnementales : hyperglycémie, anaérobie, antibiotiques (linézolide et vancomycine). Les résultats ont montré qu’une exposition prolongée (plus de 24 semaines) à ces conditions de stress notamment aux antibiotiques, réduisait la virulence des souches de SA ; iii) d’évaluer la virulence des SA en présence d’autres bactéries qui l’entourent, élément essentiel du polymicrobisme de l’UPD. Ce travail s’est particulièrement intéressé aux interactions existant entre SA et Helcococcus kunzii, bactérie fréquemment isolée en association avec le SA dans les UPD. Il a montré pour la première fois une baisse de la pathogénicité des souches de SA par une bactérie commensale non virulente. / Diabetes mellitus is a global problem. One of the main complications is diabetic foot ulcer (DFU) which can evolve towards infection and induces lower limb amputations. Those wounds are mostly polymicrobial and Staphylococcus aureus (SA), the most prevalent pathogen isolated in this situation causes numerous therapeutic problems. This bacterium, known to be a commensal organism present notably in nasal cavity, is a real pathogen in DFU. However the comprehension between the commensalism and the pathogenicity of SA remains still unknown. Recently, a colonizing SA strain with very low virulence potential was discovered in DFU. This strain possesses a phage named Rosa-like responsible of its low virulence.This work helped us: i) to highlight the involvement of the Rosa-like phage in the disregulation of iron uptake mechanisms, the main source for SA survival and its global metabolism. The obtained results confirm the key role of the phage in the decrease of the colonizing SA strain virulence; ii) to study the behaviour of clinical SA strains (colonizing/infecting) using an in vitro chronic infection model miming different environmental conditions encountered in DFU: hyperglycemia, anaerobic condition, antibiotics (linezolid and vancomycin). Results showed that prolonged exposure (up to 24 weeks) to those stress conditions notably antibiotics reduced SA strains virulence; iii) to evaluate SA virulence in presence of other bacteria present in DFU. Particularly, in this work a focus was performed in the interaction between SA and Helcococcus kunzii, gram positive bacteria frequently isolated with SA in DFU. It was shown for the first time a decrease of SA pathogenicity by a commensal non virulent bacterium.

Submitted by Geyciane Santos (geyciane_thamires@hotmail.com) on 2015-06-09T13:36:11Z No. of bitstreams: 1 Dissertação - Selma Barboza Perdomo.pdf: 714589 bytes, checksum: adb7bad1bf0a14396d51897811aafd0a (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-06-09T19:36:28Z (GMT) No. of bitstreams: 1 Dissertação - Selma Barboza Perdomo.pdf: 714589 bytes, checksum: adb7bad1bf0a14396d51897811aafd0a (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-06-09T19:38:12Z (GMT) No. of bitstreams: 1 Dissertação - Selma Barboza Perdomo.pdf: 714589 bytes, checksum: adb7bad1bf0a14396d51897811aafd0a (MD5) / Made available in DSpace on 2015-06-09T19:38:12Z (GMT). No. of bitstreams: 1 Dissertação - Selma Barboza Perdomo.pdf: 714589 bytes, checksum: adb7bad1bf0a14396d51897811aafd0a (MD5) Previous issue date: 2008-11-10 / Não Informada / The Wound Version of Ferrans and Powers about the Life Quality Rate (IQVFP-VF) was firstly applied in diabetic people with wound on the foot. The lack of specific studies made in Brazil on life quality (QV) about this population has been a motivation for this paper to be carried out, which aims at – a) describing the socio-demographic profile of the diabetic patients with wounds on the foot; b) to correlate the QV scores according to its sociodemographic characteristics e; c) to describe the clinic characteristics, related to Diabetes mellitus (DM). This study has been descriptive, transversal, carried out through interviews and IQVFP-VF application on people who have been assisted in three different public services in Manaus-AM, where two in ambulatories and one at an internment sector of vascular surgery. The IQVFP-VF was built up and certified by Yamada (2006) and it is constituted of 70 items divided into four dominions: Health/Functioning (SF), Socioeconomics (SE), Psychological/Spiritual (PE), and Family (Fa). Initially the study received the author’s instrument authorization, also a favorable opinion of the Amazon Federal University - UFAM’s Ethic Committee, and the Hospitals’ authorization for datum gathering. There was a predominance of: men (54%); average age of 59,65 years old; people in stable matrimony (47,5%); Catholics (82%); dismissal from labor activities because of the wound (36%). About the clinical conditions there was: DM predominance type 2; average age of 9,89 years old for the time with the DM; use of oral hypoglycemia and balanced alimentation as a way to control glucose. Concerning to the wound it was verified: 1,19 wound average; 29,5% of the samples had a wound unleashing factor, the bruise by cutting/perforating object when walking bare foot; 31,1% with amputation. For a better results discussion it was used adistributed categorization in such a way that “zero” indicates very bad QV and 30 very good QV. Concerning to the QV, we had an average scores of 20,66 (±5,29) for IQVT. The most affected dominion was the Health/Functioning with an average score of 17,07 (±6,46) and with the highest score the PE with the average of 25,96 (±6,12). There was not correlation among the variables: professional activity, age, number of wounds, time with the DM; with the IQVT. There was a positive, but weak, correlation between family income (r=0,11), sex (r=0,11), time with the wound (r=0,11) and a strong correlation among amputation (r=0,49) and IQVT and its dominion. Patient in stable matrimony situation had an average higher than the others under Fa dominion (p=0,045). There was no meaningful difference either among intern patients and the ones who had been assisted at the ambulatories in the IQVT nor in its dominions. In conclusion, it has been attested that the IQVFP-VF is adequate to assess the diabetics’ life quality with wounds on the feet, and this population has shown to have a life quality considered “good”, but it has shown low score in the Health/Functioning dominion showing that the wound on the diabetic’s foot is a complication from the DM that has negative impact over these people’s life quality. / O Índice de Qualidade de Vida de Ferrans e Powers–Versão Feridas (IQVFP-VF) foi aplicado pela primeira em pessoas diabéticas com ferida no pé após sua construção e validação. A escassez de estudos realizados, no Brasil, específicos acerca da Qualidade de Vida (QV) nessa população, foi a motivação para realizar este estudo que teve como objetivos: a) descrever o perfil sócio-demográfico dos pacientes diabéticos com ferida no pé; b) correlacionar os escores de Qualidade de Vida segundo as características sócio-demográficas e c) descrever as características clínicas, relacionadas ao Diabetes mellitus (DM). O estudo foi descritivo, transversal, realizado por meio de entrevista e aplicação do IQVFP-VF nas pessoas atendidas em três serviços públicos da cidade de Manaus-AM, sendo dois ambulatórios e um setor de internação de cirurgia vascular. O IQVFP-VF foi construído e validado por Yamada (2006) é composto por 70 itens e está dividido em quatro subescalas: Saúde/Funcionamento (SF), Sócio-Econômico (SE), Psicológico/Espiritual (PE), e Família (Fa). Inicialmente o estudo recebeu autorização da autora do instrumento, parecer favorável do Comitê de Ética da Universidade Federal do Amazonas-UFAM e autorizações dos hospitais para a coleta dos dados. Houve predomínio de: homens (54%); idade média de 59,65 anos; pessoas com união estável (47,5%); católicos (82%); afastamento da atividade profissional por causa da ferida (36%). A respeito das condições clínicas houve: predomínio de DM do tipo 2; média de 9,89 anos para o tempo com DM; uso de hipoglicemiante oral e alimentação balanceada com forma de controle da glicemia. Concernente à ferida ficou constatado: média de 1,19 feridas; 29,5% da amostra tiveram como fator desencadeador da ferida objeto cortante/perfurante ao andar descalço; 31,1% com amputação. Para melhor discussão dos resultados, foi utilizada categorização distribuída de tal forma que “zero” indica QV muito ruim e 30 QV muito boa. Acerca da QV, foi obtido escore médio de 20,66 (±5,29) para IQVT. O Domínio mais afetado foi o Saúde/Funcionamento com escore médio de 17,07 (±6,46) e com maior escore o PE com média de 25,96 (±6,12). Não houve correlação entre as variáveis: atividade profissional, idade, número de feridas, tempo de DM, com o IQVT. Houve correlação positiva, porém fraca, entre renda familiar (r=0,11), sexo (r=0,11), tempo com a ferida (r=0,11) e correlação forte entre amputação (r=0,49) e IQVT e seus domínios. Os pacientes com união estável tiveram média superior aos demais no Domínio Fa (p=0, 045). Em conclusão, ficou constatado que o IQVFP-VF é adequado para avaliar a QV de diabéticos com ferida no pé, que essa população mostrou ter qualidade de vida “boa”, porém, apresentou escore baixo no Domínio Saúde/Funcionamento demonstrando que a ferida no pé do diabético é uma complicação do DM que tem impacto negativo sobre a Qualidade de Vida dessas pessoas.

Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-09-09T19:52:40Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) CAROLINE DA SILVA SILVEIRA.pdf: 6734641 bytes, checksum: 8df9bfda7306dbc3b2714620b6612002 (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-09-09T19:52:54Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) CAROLINE DA SILVA SILVEIRA.pdf: 6734641 bytes, checksum: 8df9bfda7306dbc3b2714620b6612002 (MD5) / Made available in DSpace on 2016-09-09T19:52:54Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) CAROLINE DA SILVA SILVEIRA.pdf: 6734641 bytes, checksum: 8df9bfda7306dbc3b2714620b6612002 (MD5) Previous issue date: 2016-02-23 / Doenças podais são uma das principais injúrias em rebanhos de pequenos ruminantes em diversos países e a pododermatite infecciosa (Footrot) é relatada como a mais frequente em ovinos no Brasil. No Rio Grande do Sul, as doenças podais ainda são um grave problema para os criadores de ovinos e pouco tem sido feito para saná-las. O Footrot, mesmo se tratando de uma doença de notificação obrigatória e frequente na região, os registros oficiais sobre a situação da doença nos rebanhos são escassos. Esse trabalho teve como objetivo descrever as principais características das lesões podais observadas em ovinos da Mesorregião Sudoeste do Rio Grande do Sul, com ênfase nos aspectos epidemiológicos, macroscópicos, microscópicos e radiográficos das lesões de Footrot. O estudo foi realizado em duas etapas. Inicialmente foram avaliados ovinos em 27 propriedades rurais, das quais 21 registraram a ocorrência de lesões podais em ovinos com perdas econômicas significativas. Aproximadamente 1.700 ovinos, em média 10% dos animais do rebanho, apresentavam diferentes graus de claudicação decorrente de lesões podais que, macroscopicamente, variavam de brandas a severas. Posteriormente, foram avaliados os variados graus de lesões de Footrot nos ovinos. Em casos de abate e necropsia, os cascos dos ovinos com as lesões foram submetidos à avaliação macroscópica, radiográfica e microscópica. Dessa forma a doença foi classificada em cinco graus de severidade que variaram de 1 (lesões leves) a 5 (lesões graves). Verificou-se que diversos fatores como clima e manejo foram favoráveis para o desenvolvimento das lesões podais e essas estão associadas, na maioria dos casos, a Footrot em diferentes estágios de evolução. A partir dessa classificação em graus foi possível classificá-los macroscopicamente em duas síndromes clínicas propostas, a saber Footrot benigno e maligno. Essa classificação facilita o estabelecimento das medidas de controle com intuito de limitar a propagação da doença e evitar a evolução das lesões nos cascos acometidos. / Foot diseases are one of the main disorders in small ruminant flocks in several countries and infectious pododermatite (Footrot) is reported as the most frequent podal lesions in sheep in Brazil. In Rio Grande do Sul state, foot diseases still a serious problem for sheep farmers and little has been done to remedy them. Footrot is a notifiable disease and frequent in the region, the official records on the disease situation in herds are scarce. This study aimed to describe the main features of foot lesions observed in sheep from Mesoregion Southwest of Rio Grande do Sul, with emphasis on epidemiology, macroscopic, microscopic and radiographic changes of Footrot injuries. The study was conducted in two steps. Initially, sheep were evaluated on 27 farms, of which 21 showed records of the occurrence of foot lesions in sheep and significant economic losses. Approximately 1,700 sheep, about 10% of the flocks, showed varying degrees of lameness due to foot lesions, macroscopically characterized as mild to severe. Subsequently, they assessed the varying degrees of injuries Footrot in sheep. Hooves with injuries were submitted to macroscopic, radiographic and microscopic evaluation. Thus the disease was classified into five grades of severity ranging from 1 (mild injury) to 5 (severe damage). It has been found that several factors such as weather and handling were favorable for the development of foot injuries and these are associated in most Footrot cases in different stages of evolution. Based on the classification in degrees of infectious pododermatitis it was possible to classify them macroscopically in clinical syndromes proposed as benign and malignant Footrot. This classification facilitates the establishment of control measures with the intention of reduce spread of disease and prevent the development of lesions in affected hooves.

Problem: Running is one of the most widespread physical activities. Incorrect running technique, training quantity but also the runner's equipment can strongly affect health condition of the individual, both positively and negatively. For that reason various trends emerge in the area of running footwear. They include classical sports shoes with different types of impact attenuation as well as the minimalist footwear made to imitate barefoot running, which should be much more natural for humans, as insisted by B. Nigg in his book "Born to Run" - where he says that man was born to walk and run barefooted. Inappropriate shoes can cause various health complications, not only in the foot area. Objective: To find out how foot strike changes in the area of the foot-shoe interaction in running on flat ground when an amateur runner uses minimalist and sports footwear and to draw conclusions for training practice on the basis of the results. Methods: The thesis deals with amateur endurance running in different shoe types (minimalist and sports shoes). The study specimen consisted of 14 female runners (mean body weight 63,31 ± 4,89 kg, height 169,69 ± 4,71 cm, age 31,92 ± 5,34 years, speed in minimalist shoes (MO) 3,34 ± 0,06 m.s- 1 , speed in sports shoes (SO) 3,29 ± 0,06 m.s-1 , weekly mileage 37,54 ± 9,43...

abstract: Locomotion is of prime importance in enabling human beings to effectively respond in space and time to meet different needs. Approximately 2 million Americans live with an amputation with most of those amputations being of the lower limbs. To advance current state-of-the-art lower limb prosthetic devices, it is necessary to adapt performance at a level of intelligence seen in human walking. As such, this thesis focuses on the mechanisms involved during human walking, while transitioning from rigid to compliant surfaces such as from pavement to sand, grass or granular media. Utilizing a unique tool, the Variable Stiffness Treadmill (VST), as the platform for human walking, rigid to compliant surface transitions are simulated. The analysis of muscular activation during the transition from rigid to different compliant surfaces reveals specific anticipatory muscle activation that precedes stepping on a compliant surface. There is also an indication of varying responses for different surface stiffness levels. This response is observed across subjects. Results obtained are novel and useful in establishing a framework for implementing control algorithm parameters to improve powered ankle prosthesis. With this, it is possible for the prosthesis to adapt to a new surface and therefore resulting in a more robust smart powered lower limb prosthesis. / Dissertation/Thesis / Masters Thesis Biomedical Engineering 2019

The contribution of the midfoot in landing mechanics is understudied. Therefore, the main purpose of this study was to quantify midtarsal joint kinematics and kinetics during a barefoot single-leg landing task. A secondary aim of this study was to explore the relationship between static foot posture and dynamic midfoot function. In a cross-sectional study design, 48 females (age = 20.4 ± 1.8 yr, height = 1.6 ± 0.06 m, weight = 57.3 ± 5.5 kg, BMI = 21.6 ± 1.7 kg·m-1) performed drop landings from a height of 0.4 m onto split force platforms. Subjects hung from wooden rings and landed on their dominant leg. Midtarsal joint kinematic and kinetic data were recorded using a motion capture software system in conjunction with a custom multisegment foot model marker set. Arch height index (AHI) for both seated and standing conditions was measured using the Arch Height Index Measurement System (AHIMS). Kinematic data revealed an average sagittal plane midtarsal range of motion (ROM) of 27 degrees through the landing phase. Kinetic data showed that between 7% and 22% of the total power absorption during the landing was performed by the midtarsal joint. Standing AHI was correlated negatively with sagittal plane midtarsal ROM (p = 0.0264) and positively with midtarsal work (p = 0.0212). Standing midfoot angle (MA) was correlated positively with sagittal plane midtarsal ROM (p = 0.0005) and negatively with midtarsal work (p = 0.0250). The midfoot contributes substantially to landing mechanics during a barefoot single-leg landing task. Static foot posture may be a valuable measurement in predicting midfoot kinematics and kinetics.

Sprinters are always looking for an improvement in their time, from the gun going off until the finish. An effective start can lead to reaching top velocity sooner and a decreased finish time. New developments in starting blocks, more specifically the width of the starting block pedal, has allowed for variation in foot placement in the blocks. With the ability to change how wide an athlete can place their feet in the blocks, this study looked at trying to find an optimum spacing for college level sprinters. Thirteen Male College Sprinters (mean age = 23.08 years) participated in this study. Subjects self selected their longitudinal block spacing with 3 different lateral positions being tested. In position 1, the feet were placed as narrow as was allowed by the starting block, simulating the width of a traditional set of blocks. Position 2 was defined by the hip width of the individual, distance between right ASIS to left ASIS. Position 3 was the preferred foot width of the subject as determined by completing a vertical jump. Measurements of peak force on the blocks at the time of the start as well as time to 10 m were taken. Neither peak force nor time to 10 m were different between conditions (p = .887, p = .135). The normal condition, position 1 (20cm), was measured to be the narrowest width with position 3 (mean = 37.6cm) being the widest in all subjects. The use of wider pedals on starting blocks is a fairly new idea in track and field, and is something that many athletes have not had the chance to practice with. Since the older style of starting blocks only allowed for a narrow stance that is what track athletes have become accustomed to and could possibly explain why there was no significant difference seen between the 3 starting positions. More research should be done after a time of adaptation to the new starting blocks by the athletes.

Tumbling take-offs on floor exercise apparatuses of varying stiffness properties may contribute to apparatus behaviors that lead to increased injury exposure. The purpose of this pilot study was to compare the kinematics, kinetics, and timing performance characteristics of a springfloor and a spring-floor with an added Air FloorTM. Five male international gymnasts performed a forward handspring to forward somersault and a round off, flic flac, backward somersault on a standard spring-floor and a spring-floor with an Air FloorTM. Performances were measured via high-speed video kinematics (lower extremity joint angles and positions), electromyography of eight lower extremity muscles, mean peak forces on the feet, and timing. Comparisons of spring-floor types, lower extremity joint angles, lower extremity muscle activations, foot forces, and selected durations were determined. The spring floor with Air FloorTM resulted in longer take-off contact durations than spring-floor alone. Dynamic knee angles may indicate an unexpected and potentially injurious motion of the triceps surae musculotendinous structures. This pilot and hypothesis generating study has suggested future research examining dynamic knee position and angle changes, the role of spring-floor vibration and stiffness in take-offs, and take-off muscle activation alignment with the stiffness of the spring-floor. Pragmatically, there appears to be a convergence of evidence indicating that a slower frequency response of the spring floor may assist tumbling performance and reduce stress and strain in the lower extremity.