Ground reaction force patterns during gait in patients with lower limb lymphedema

Although gait problems have been reported in patients with lower limb lymphedema (LLL), the gait pattern (GP) changes have not been documented yet. However, it is possible that patients with LLL show abnormal GP that can be related to biomechanical complications related to osteoarthritis or falls affecting the quality of life. Ground reaction force analysis during gait allows objective assessment of the patients and it can be used to plan a rehabilitation approach. Objective: To analyze the GRF during gait in patients LLL. Methods: An experimental descriptive study was realized with twenty-three LLL patients, both unilateral and bilateral and classified as moderate and severe, participated in the experiments. The patients walked on a force plate while the three ground reaction force (GRF) components, vertical, mediolateral (M-L) and anteroposterior (A-P), under their feet were recorded and analyzed. Results: In the patients with unilateral lymphedema, either moderate or severe, the vertical GRF components of the affected limb were similar to the sound one and also resembling those found in healthy adults. The M-L GRF was smaller in the non-affected side. In patients with bilateral lymphedema gait speed was significantly slower. More interestingly, the vertical GRF pattern was flat, not showing the typical 2-peak shape. Finally, the large M-L forces found suggest gait stability problems. Conclusions: The patients showed abnormal GRF patterns, including compensation with the non-affected leg. The GRF variability was higher in the patients with severe unilateral lymphedema. Bilateral lymphedema results in lower A-P forces. Stance phase duration was longer in patients with bilateral and severe lymphedem

BIOMECHANICAL DESIGN OF FOOTBALL BOOTS: EFFECT OF STUDS ON PERFORMANCE AND INJURY PREVENTION

Football boots can have an effect on performance and on footballers’ injuries (Chan et al., 1993; Masson and Hess, 1989). With the purpose of studying and improving such effects, 5 football boot prototypes were made, with the same materials, design and upper construction, but a different number and distribution of studs on the soles. Previously, an initial prototype was made taking into account biomechanical and anatomical criteria, the foot areas better prepared to support mechanical loads and the effect of the distribution of studs on the axes of foot movement and the braking and drive forces during displacements.1 Tests were carried out with test subjects ( football players)2 who made performance tests on an obstacle course (Brizuela et al., 1997) using an electronic chronograph system, rear foot stability tests during fast movements in changes of direction by means of electrogoniometers, plantar pressure distribution tests during running by means of instrumented insoles and comfort tests during the normal practice of football by means of subjective evaluation questionnaires. All these tests were performed using a natural turf field. The results show that boots with a greater number of studs (15, 14 studs) caused poorer performance than those with a lesser number (13 studs), less comfort during use and a greater plantar pressure distribution. Regarding the distribution of studs, the different configurations yielded significant differences in the rear foot stability test, comfort during use and plantar pressure distribution results. The best results in regard to these aspects were achieved by the prototype with 13 studs, which was designed according to biomechanical and anatomical criteria. As a conclusion, we can point out that the design of the football boot sole, in particular the distribution of studs according to biomechanical criteria, can positively affect relevant aspects for the practice of football, which can increase subjective comfort without diminishing performance and can also be related3 to the prevention of footballers’ injuries. REFERENCES: Brizuela, G., Llana, S., Ferrandis, R., García-Belenguer, A. (1997). The Influence of Basketball Shoes with Increased Ankle Support on Shock Attenuation and Performance in Running and Jumping. Journal of Sports Sciences 15, 5, 505-515. Chan, K.M., Yuan, Y., Li, C.K., Chien, P., Tsang, G. (1993). Sports Causing Most Injuries in Hong Kong. J. Sports Med. 27, 4, 263-267. Masson, M., Hess, H. (1989). Typical Soccer Injuries. Their Effects on the Design of the Athletic Shoe. In B. Segesser, W. Pförringer (Eds.), The Shoe in Sport. London, Wolfe Publishing Ltd., 89-95

Frecuencia cardíaca en tiempo real y por telemetría para aplicaciones acuáticas

El registro de la frecuencia cardíaca (FC) es un parámetro muy útil para el control y la planificación del entrenamiento deportivo. Existen diversos sistemas de cardiotacómetros miniatura en el mercado diseñados y fabricados para su uso en actividades físico-deportivas. Todos ellos se colocan en el pecho mediante una cinta elástica, que proporciona una fijación insuficiente para la natación, especialmente en los virajes, ello obliga a utilizar cinta adhesiva u otros sistemas de fijación "cruentos". El sistema desarrollado en el Instituto de Biomecánica de Valencia (IBV) permite registrar y enviar telemétricamente la fre-cuencia cardíaca a un ordenador personal donde se puede mostrar en tiempo real y/o ser almacenada para su posterior análisis. De esta manera, el entrenador puede controlar la intensidad de un entreno y transmitir un feedback casi inmediato al nadador. El sistema consiste en una pinza colocada en el lóbulo de la oreja con un emisor de luz roja (LED) y una resistencia dependiente de la luz (LDR). La luz roja pasa a través del lóbulo y es recibida por el LDR. El fun-damento del sistema consiste en que la atenuación de la luz roja en el lóbulo de la oreja está asociada con cambios en el contenido de sangre oxigenada, método denominado "oximetría". Para el sistema de telemetría se utiliza un modulador de señal basado en un oscilador controlado por tensión (VCO) y un circuito comercial híbrido para la transmisión. El cálculo de la frecuencia cardíaca en tiempo real es posible gracias a la utilización de un filtro digital y al desarrollo de un algoritmo para reducir el ruido

EFFECT OF FOOTWEAR ON LATERAL BRAKING AND TURNING MOVEMENTS IN TENNIS

INTRODUCTION: Lateral displacements can be considered the most characteristic type of displacements in tennis, and therefore they have been the most studied movement in tennis footwear research (Luethi et al., 1986, Nigg et al., 1989). The present study was conducted to analyze the cinematic and kinetic variables affected by tennis footwear in lateral braking and turning movements. METHODS: The sample of footwear used comprised the ten best-selling tennis shoes available in Valencia, and the subjects were 5 players who met a set of previously set requirements. Each player performed a lateral braking and turning movement five times on an extensometric force plate with a sampling frequency of 1000 Hz. The movements were filmed with a photogrammetry-video system at 50 Hz with the kinetic model of Vaughan and cols. (1992) Each parameter in the study was considered a statistical variable with which an ANOVA was made, taking the subjects and the shoes as factors, with a significance level of 0.05 and making a post hoc with LSD methodology. With the kinematic and kinetic variables dependent on footwear a Pearson type correlation analysis was made. RESULTS: The kinematic variables most affected by footwear were ankle flexoextension and subastragalar prono-supination. The footwear-dependent kinetic variables were the second maximum of the vertical and mediolateral (p=0.032) components of reaction forces, as well as the time lapse between the two maximums. Prono-supination values correlated both to the maximums of vertical (r=-0.1224, p=0.028) and medio-lateral forces and to the time lapse between the two maximums. The footwear that controls (limits) the prono-supination movements related to higher force levels in the second maximum of the vertical and medio-lateral components, as well as with lower time lapse between maximums. Consequently, the control of prono-supination movement becomes a performance criterion in lateral displacements, since it permits subjects to perform these displacements faster. REFERENCES: Nigg, B.M., Luethi, S.M., Bahlsen, H.A. (1989). The tennis shoes. Biomechanical design criteria. The shoe in sport, B. Segesser, W. Pförringer (Eds.). Wolfe Publishing, Ltd. Luethi, S.M., Frederick, E.C., Hawes, M.R., Nigg, B.M. (1986). Influence of shoe construction on lower extremity kinematics and load during lateral movements in tennis. Int. J. Sport Biomech. 2, 3, 166-174

Mitigation needs adaptation: Tropical forestry and climate change

International audienceThe relationship between tropical forests and global climate change has so far focused on mitigation, while much less emphasis has been placed on how management activities may help forest ecosystems adapt to this change. This paper discusses how tropical forestry practices can contribute to maintaining or enhancing the adaptive capacity of natural and planted forests to global climate change and considers challenges and opportunities for the integration of tropical forest management in broader climate change adaptation. In addition to the use of reduced impact logging to maintain ecosystem integrity, other approaches may be needed, such as fire prevention and management, as well as specific silvicultural options aimed at facilitating genetic adaptation. In the case of planted forests, the normally higher intensity of management (with respect to natural forest) offers additional opportunities for implementing adaptation measures, at both industrial and smallholder levels. Although the integration in forest management of measures aimed at enhancing adaptation to climate change may not involve substantial additional effort with respect to current practice, little action appears to have been taken to date. Tropical foresters and forest-dependent communities appear not to appreciate the risks posed by climate change and, for those who are aware of them, practical guidance on how to respond is largely non-existent. The extent to which forestry research and national policies will promote and adopt management practices in order to assist production forests adapt to climate change is currently uncertain. Mainstreaming adaptation into national development and planning programs may represent an initial step towards the incorporation of climate change considerations into tropical forestry

Freqüència cardíaca en temps real i per telemetria per a aplicacions aquàtiques

El registre de la freqüència cardíaca (FC) és un paràmetre molt útil per al control i la planificació de l'entrenament esportiu. AI mercat hi ha diversos sistemes de cardiotacòmetres miniatura dissenyats i fabricats per a ús en activitats fisicoesportives. Tots es col·loquen al pit mitjançant una cinta elàstica, que proporciona una fixació insuficient per a la natació, especialment en els viratges, això obliga a utilitzar cinta adhesiva o altres sistemes de fixació "cruents". El sistema desenvolupat a l'Institut de Biomecànica de València (IBV) permet registrar enviar telemètricament la freqüència cardíaca a un ordinador personal on es pot mostrar en temps real i/o ser emmagatzemada per a posterior anàlisi. D'aquesta manera, l'entrenador pot controlar la intensitat d'un entrenament i transmetre un feedback gairebé immediat al nedador. El sistema consisteix en una pinça col·locada al lòbul de l'orella amb un emissor de llum vermella (LED) i una resistència depenent de la llum (LDR). La llum vermella passa a través del lòbul i és rebuda pel LDR. El fonament del sistema consisteix que l'atenuació de la Ilum vermella en el lòbul de l'orella està associada amb canvis en el contingut de la sang oxigenada, mètode anomenat "oximetria". Per al sistema de telemetria es fa servir un modulador de senyal basat en un oscil·lador controlat per tensió (VCO) i un circuit comercial híbrid per a la transmissió. El càlcul de la freqüència cardíaca en temps real és possible gràcies a la utilització d'un filtre digital i al desenvolupament d'un algoritme per reduir el soroll

Modelo transteórico de mudança de comportamentos na promoção da actividade física nas grávidas

Determinar se o Modelo Transteórico de Mudança de Comportamento (MTMC) é eficaz na promoção da actividade física (AF) nas grávidas. O grupo experimental (GE) participou no projecto “Mães em Movimento” baseado no MTMC. Aplicou-se o Questionário de AF para Gestantes, Escala de Estados de Mudança, Behavioural Regulation in Exercise Questionnaire e Questionário de Conhecimentos. Na 2ª avaliação, no GE, todas as grávidas referiram praticar AF. A motivação intrínseca e os conhecimentos aumentaram. O MTMC revelou-se um modelo eficaz na promoção da AF em grávidas.To determine whether the Transtheoretical Model of Behavior Change (TTM) is effective in promoting physical activity (PA) in pregnant women. The experimental group (EG), participated in the "Moms in Motion" based on the TTM. It was applied the Pregnancy Physical Activity Questionnaire, Stages of Change Questionnaire, Behavioral Regulation in Exercise Questionnaire and Skills Questionnaire. In the 2nd evaluation, in EG, all women reported practicing PA. The intrinsic motivation and knowledge increased. The TTM revealed to be an effective model in promoting PA habits in pregnant women

Analysis of the human interaction with a wearable lower-limb exoskeleton

The design of a wearable robotic exoskeleton needs to consider the interaction, either physical or cognitive, between the human user and the robotic device. This paper presents a method to analyse the interaction between the human user and a unilateral, wearable lower-limb exoskeleton. The lower-limb exoskeleton function was to compensate for muscle weakness around the knee joint. It is shown that the cognitive interaction is bidirectional; on the one hand, the robot gathered information from the sensors in order to detect human actions, such as the gait phases, but the subjects also modified their gait patterns to obtain the desired responses from the exoskeleton. The results of the two-phase evaluation of learning with healthy subjects and experiments with a patient case are presented, regarding the analysis of the interaction, assessed in terms of kinematics, kinetics and/or muscle recruitment. Human-driven response of the exoskeleton after training revealed the improvements in the use of the device, while particular modifications of motion patterns were observed in healthy subjects. Also, endurance (mechanical) tests provided criteria to perform experiments with one post-polio patient. The results with the post-polio patient demonstrate the feasibility of providing gait compensation by means of the presented wearable exoskeleton, designed with a testing procedure that involves the human users to assess the human-robot interaction

Malacofauna from a building dated to VII-VI centuries BC at the archaeological site of Puig de Vinaròs (the Baix Maestrat)

Aquest treball classifica el material del fílum Mollusca, tant d’origen marí com continental, que s’ha trobat en un departament de l’edifici fortificat en un assentament del Ferro Antic dels segles VII-VI a. de C., situat al cim d’un turó a Vinaròs (el Baix Maestrat; País Valencià). La residència fortificada devia pertànyer a l’elit que controlava el territori dels voltants. La intenció del treball és complementar la informació obtinguda per la resta del material arqueològic, amb dades sobre la malacofauna contemporània a l’assentament, atès que bona part mostra signes d’haver patit l’incendi que va afectar l’habitacle. El material es va obtenir en les campanyes d’excavació del 2016 i el 2018 i tot pertany a un mateix moment cronològic. En el departament hi havia conquilles de 5 espècies de mol·luscs marins i 4 continentals. Els mol·luscs marins van ser recollits intencionadament a la tanatocenosi d’una platja de grava i transportats a la residència fortificada. No se’n va fer un ús gastronòmic, perquè quan es van recollir ja eren conquilles buides, amb incrustants en l’interior de les valves, mostres evidents d’haver estat arrossegats i erosionats per l’onatge, presència de perforacions de depredadors marins. No presenten treballs antròpics. Cal considerar una intenció recreativa.Dels mol·luscs continentals no hi ha dades per a interpretar que van ser recollits intencionadament. Per l’exis-tència d’algun exemplar cremat s’han considerat coetanis a l’incendi o colgats de forma natural en un període posterior relativament pròxim. Pel conjunt de les característiques ecològiques de les quatre espècies s’ha inferit que l’aspecte i la vegetació d’aquell moment seria molt semblant a l’actual (matollar mediterrani o timonedes) i que per tant ja s’havia produït una intervenció en l’entorn, havent desforestat el boscos originals, als voltants de l’assentament, mitjançant l’ús del foc, actuació que podria ser bastant anterior al procés de construcció de l’edifici.This work classifies material of the phylum Mollusca, of both marine and continental origin, which was found within a fortified building in an Iron Age Iberian settlement dated to the VII-VI centuries BC, located on a hilltop in Vinaròs (the Baix Maestrat; Valencian Country). It is highly probable that the fortified residence belonged to the elite who controlled the surrounding territory. The objective of the work is to supplement the information obtained from the rest of the archaeological mate-rial with data on the contemporary malacological fauna in the settlement, since much of it shows signs of having suffered from the fire that affected the building. The material was obtained in the excavation campaigns of 2016 and 2018 and was found in the same stratigra-phic level. The shells of 5 species of marine and 4 continental molluscs were found within the building.Marine molluscs were intentionally collected from the thanatacoenoses of a gravel beach and transported to the fortified residence. Given that the shells had marine encrustations within them, showed obvious signs of having been dragged and eroded through wave action and had perforations caused by marine predators, it is clear that they were empty when collected and could not have been used as a food source. It must therefore be assumed that there was some other reason, maybe recreational, for their collection.With regards to the continental molluscs, there is no data showing that they were collected intentionally. The presence of some burned specimens could be interpreted as showing that they were contemporary with the fire or buried naturally soon afterwards. The ecological characteristics of the four species allows us to infer that the appearance and vegetation of that time was very similar to the current one (Mediterranean scrub) and that therefore some clearing of the original forests, probably through the use of burning, had already taken place and that could have occurred quite some time prior to the construction of the building