Predictors of metabolic energy expenditure from body acceleration and mechanical energies in new generation active computer games

The following paper is an original research project which uses state of the art sport science physiological and biomechanical approaches to gain information about active computer games. This project is found to be particular relevant for the field of computer science in sport, since biomechanical and physiological knowledge is required to model, track and understand human motion during computer game play

Immune responses to next generation computer gaming

The purpose of this study was to investigate stress (as measured by cortisol) and immune response (s-IgA was used as a marker) to step aerobics on the Nintendo Wii between people with varying degrees of cardiorespiratory fitness (fair and good). Measures were taken at baseline and then after participants had attended three 30 minute sessions each week for four weeks. Following a washout period, measures were taken again. More specifically, before and after a four week control period (no Nintendo Wii exercise programme). A basic health screen (blood pressure, body composition and estimated VO2max) was also carried out and cardiorespiratory responses to exercise recorded. Results revealed that the exercise intervention was vigorous enough at the start to induce a significant (p ≤ .05) increase in cortisol in the fair fitness group, but not at any other time for either fitness group. The exercise did not elicit any significant (p > .05) changes in s-IgA, regardless of fitness. Although there was a 26% reduction in s-IgA secretion rate following exercise in the fair fitness group. BP, estimated VO2max and body composition were not significantly (p > .05) altered as a consequence of exercise in the fair fitness group. In contrast, SBP and estimated VO2max were significantly (p ≤ .05) improved in the good fitness group. METs, HR, relative VO2 and EE decreased in both groups, but only significantly (p ≤ .05) for the fair fitness group. It was concluded that regular exercise on the Nintendo Wii does not improve immunosurviellence. If anything, it may even have the opposite effect in low conditioned individuals due to a temporary increase in stress hormones when first starting a structured exercise programme. Moreover, exercise on Wii step is sufficient enough in intensity to contribute to physical activity recommendations to elicit health benefits

Muscle activation patterns in shoulder impingement patients

Introduction: Shoulder impingement is one of the most common presentations of shoulder joint problems 1. It appears to be caused by a reduction in the sub-acromial space as the humerus abducts between 60o -120o – the 'painful arc'. Structures between the humeral head and the acromion are thus pinched causing pain and further pathology 2. Shoulder muscle activity can influence this joint space but it is unclear whether this is a cause or effect in impingement patients. This study aimed to observe muscle activation patterns in normal and impingement shoulder patients and determine if there were any significant differences. Method: 19 adult subjects were asked to perform shoulder abduction in their symptomatic arm and non-symptomatic. 10 of these subjects (age 47.9 ± 11.2) were screened for shoulder impingement, and 9 subjects (age 38.9 ± 14.3) had no history of shoulder pathology. Surface EMG was used to collect data for 6 shoulder muscles (Upper, middle and lower trapezius, serratus anterior, infraspinatus, middle deltoids) which was then filtered and fully rectified. Subjects performed 3 smooth unilateral abduction movements at a cadence of 16 beats of a metronome set at 60bpm, and the mean of their results was recorded. T-tests were used to indicate any statistical significance in the data sets. Significance was set at P<0.05. Results: There was a significant difference in muscle activation with serratus anterior in particular showing a very low level of activation throughout the range when compared to normal shoulder activation patterns (<30%). Middle deltoid recruitment was significantly reduced between 60-90o in the impingement group (30:58%).Trends were noted in other muscles with upper trapezius and infraspinatus activating more rapidly and erratically (63:25%; 60:27% respectively), and lower trapezius with less recruitment (13:30%) in the patient group, although these did not quite reach significance. Conclusion: There appears to be some interesting alterations in muscle recruitment patterns in impingement shoulder patients when compared against their own unaffected shoulders and the control group. In particular changes in scapula control (serratus anterior and trapezius) and lateral rotation (infraspinatus), which have direct influence on the sub-acromial space, should be noted. It is still not clear whether these alterations are causative or reactionary, but this finding gives a clear indication to the importance of addressing muscle reeducation as part of a rehabilitation programme in shoulder impingement patients

DXA-derived body composition and jump mechanical performance in sub-elite rugby union players

The purpose of this study was to investigate the associations of body composition, force and velocity on squat jump height and countermovement jump height in male sub-elite university rugby union players. Seventeen male sub-elite university rugby union players performed a countermovement jump (1kg) and squat jumps using ascending loads of 1kg, 20kg, 40kg and 60kg on one single testing session at the beginning of the season. Linear force-velocity associations and body composition using dual x-ray absorptiometry (DXA) were derived, and the following variables were acquired: total body less head (TBLH) lean mass (kg), legs lean mass (kg), TBLH body fat %, TBLH fat mass (kg), theoretical maximal force (N/kg) and theoretical maximal velocity (m•s-1). The players TBLH body fat % had a statistically significant correlation with the countermovement jump height 1kg (r= -0.723, p= 0.001), squat jump height 1kg (r= -0.608, p= 0.010), squat jump height 20kg (adjusted r2= 0.238, p= 0.027) and squat jump height 40kg (adjusted r2= 0.207, p= 0.038). TBLH fat mass also influenced the countermovement jump height 1kg (r= -0.736, p= <0.001), squat jump height 1kg (r= -0.683, p= -0.003), squat jump height 20kg (adjusted r2= 0.292, p= 0.015), squat jump height 40kg (adjusted r2= 0.212, p= 0.036) and theoretical maximal velocity (r= -0.503, p= 0.039). However, TBLH lean mass, leg lean mass, theoretical maximal force and theoretical maximal velocity had no statistically significant association on the countermovement jump or any of the squat jump loading conditions. This suggests that reducing the amount of TBLH fat mass and TBLH body fat % will improve jump performance, although having more overall mass and lean mass is not necessarily advantageous for improving jump performance. Therefore, the present study provides foundational data for future research to further investigate the associations between body composition, force, velocity and jump height in male rugby union players

Patterns of sedentary behavior : insights from observational and experimental studies on body composition and energy expenditure

It is recognized that sedentary behavior (SB) has deleterious effects on numerous health outcomes and it appears that physiological mechanisms underlying these harms are distinct from the ones explaining moderate-to-vigorous physical activity (MVPA) benefits. Sedentary behavior represents a large portion of human’s life and is increasing with technological development. A new current of opinion supports the idea that the manner SB is accumulated plays an important role. This dissertation presents six research studies conducted under the scope of SB. In the methodological area, the first study highlighted the magnitude of potential errors in estimating SB and its patterns from common alternative methods (accelerometer and heart rate monitor) compared to ActivPAL. This study presented the accelerometer as a valid method at a group level. Two studies (2 and 5) were performed in older adults (the most sedentary group in the population) to test the associations for SB patterns with abdominal obesity using accelerometry. The findings showed positive graded associations for prolonged sedentary bouts with abdominal obesity and showed that those who interrupted SB more frequently were less likely to present abdominal obesity. Therefore, public health recommendations regarding breaking up SB more often are expected to be relevant. The associations between sedentary patterns and abdominal obesity were independent of MVPA in older adults. However, the low MVPA in this group makes it unclear whether this independent relationship still exists if highly active persons are analysed. Study 3 inovates by examining the association of SB with body fatness in highly trained athletes and found SB to predict total fat mass and trunk fat mass, independently of age and weekly training time. Study 4 also brings novelty to this research field by quantifying the metabolic and energetic cost of the transition from sitting to standing and then sitting back down (a break), informing about the modest energetic costs (0.32 kcal·min−1). Finally, from a successful multicomponent pilot intervention to reduce and break up SB (study 6), an important behavioral resistance to make more sit/stand transitions despite successfully reducing sitting time (~ 1.85 hours·day-1) was found, which may be relevant to inform future behavioral modification programs. The present work provides observational and experimental evidence on the relation for SB patterns with body composition outcomes and energy regulation that may be relevant for public health interventions.É reconhecido, que o comportamento sedentário (CS) tem efeitos nefastos em enúmeros parâmetros de saúde, sendo que os mecanismos fisiológicos subjacentes a esses malefícios são distintos daqueles que explicam os benefícios da actividade física moderada a vigorosa (AFMV). O comportamento sedentário representa uma grande parte da vida do ser humano e está a aumentar a par do desenvolvimento tecnológico. Uma nova corrente de opinião defende a ideia de que a forma como o CS é acumulado poderá ter um papel importante. A presente dissertação inclui seis artigos realizados no âmbito do estudo do CS. Na área metodológica, o primeiro estudo destaca a magnitude dos potenciais erros na estimativa do CS e interrupções deste comportamento através de métodos objectivos de avaliação da AF (acelerómetro e monitor de frequência cardíaca) em comparação com o ActivPAL. Este estudo apresenta o acelerómetro como um método válido ao nível de grupo. Foram realizados dois estudos (2 e 5) em idosos (o grupo mais sedentário da população) para testar as associações dos padrões de acumulação do CS com a obesidade abdominal utilizando acelerometria. Os resultados mostraram associações positivas para períodos continuos e prolongados em CS com a obesidade abdominal, sendo que quem interrompe o CS com maior frequência está menos propenso a apresentar obesidade abdominal. Portanto, as recomendações de saúde pública para que se interrompa o CS mais frequentemente são esperadas relevantes. As associações encontradas entre os padrões de acumulação do comportamento sedentário e a obesidade abdominal foram independentes da AFMV em idosos. No entanto, a baixa AFMV neste grupo faz com que não seja claro se essa relação de independência ainda existe, em pessoas altamente treinadas. Assim, o estudo 3 trouxe inovação, ao examinar a associação do CS com a gordura corporal em atletas de alto rendimento. O CS apresentou-se como um preditor da massa gorda total e massa gorda do tronco, independentemente da idade ou do tempo de treino semanal. O estudo 4 também inova este campo de pesquisa por ter, pela primeira vez, quantificado o custo metabólico e energético de uma transição entre o estar sentado para o estar de pé e retorno à posição sentada (um “break”), informando dos custos energéticos modestos (0.32 kcal·min−1). Finalmente, de uma intervenção piloto bem sucedida que objetivou a redução e interrupção do CS (estudo 6), encontrou-se uma resistência comportamental para aumentar o número de “breaks” no CS, apesar de uma redução significativa no tempo passado sentado (1.85horas·dia-1), informando assim futuros programas de modificação comportamental. O presente trabalho fornece evidência observacional e experimental sobre a relação entre os padrões de CS com variáveis de composição corporal e regulação energética que podem ser relevantes para intervenções de saúde pública

Development and application of an optimization model for elite level shot putting

Shot putting is one of the most ancient forms of athletic competition. Considerable research has been performed on the event. Despite this fact, research examining performance in the women’s shot put and using the spin technique is very limited. Also, only one attempt has been made to optimize the movement of elite shot putting and no attempts have been made to use the optimization model as a standard for technical training intervention. A series of three experiments were used to explore the development of an optimization model for shot putting and its application as a basis for technical intervention for elite athletes. Experiment 1 served as an exploratory study that explored the feasibility of developing an optimization model for shot putting. The results indicated that there are 8 variables that are highly linked with performance in the shot put and supported the notion that an optimization model for the shot put could be developed. Experiment 2 expanded on and validated the findings of the first study. Results of this study yielded a five variable optimization model for the shot put. Finally, Experiment 3 sought to apply the optimization model developed in Experiment 2 to elite athletes. The results indicated that a technical intervention based on an optimization model produces meaningful changes in performance that can be attributed to changes in optimization model parameters

The design, construction and evaluation of sprint footwear to investigate increased sprint shoe bending stiffness on sprint performance and dynamics

The design, construction and evaluation of sprint footwear to investigate increased sprint shoe bending stiffness on sprint performance and dynamic

Aerospace Medicine and Biology: A cumulative index to a continuing bibliography

This publication is a cumulative index to the abstracts contained in Supplements 138 through 149 of AEROSPACE MEDICINE AND BIOLOGY: A CONTINUING BIBLIOGRAPHY. It includes three indexes -- subject, personal author, and corporate source

State of the art of audio- and video based solutions for AAL

Working Group 3. Audio- and Video-based AAL ApplicationsIt is a matter of fact that Europe is facing more and more crucial challenges regarding health and social care due to the demographic change and the current economic context. The recent COVID-19 pandemic has stressed this situation even further, thus highlighting the need for taking action. Active and Assisted Living (AAL) technologies come as a viable approach to help facing these challenges, thanks to the high potential they have in enabling remote care and support. Broadly speaking, AAL can be referred to as the use of innovative and advanced Information and Communication Technologies to create supportive, inclusive and empowering applications and environments that enable older, impaired or frail people to live independently and stay active longer in society. AAL capitalizes on the growing pervasiveness and effectiveness of sensing and computing facilities to supply the persons in need with smart assistance, by responding to their necessities of autonomy, independence, comfort, security and safety. The application scenarios addressed by AAL are complex, due to the inherent heterogeneity of the end-user population, their living arrangements, and their physical conditions or impairment. Despite aiming at diverse goals, AAL systems should share some common characteristics. They are designed to provide support in daily life in an invisible, unobtrusive and user-friendly manner. Moreover, they are conceived to be intelligent, to be able to learn and adapt to the requirements and requests of the assisted people, and to synchronise with their specific needs. Nevertheless, to ensure the uptake of AAL in society, potential users must be willing to use AAL applications and to integrate them in their daily environments and lives. In this respect, video- and audio-based AAL applications have several advantages, in terms of unobtrusiveness and information richness. Indeed, cameras and microphones are far less obtrusive with respect to the hindrance other wearable sensors may cause to one’s activities. In addition, a single camera placed in a room can record most of the activities performed in the room, thus replacing many other non-visual sensors. Currently, video-based applications are effective in recognising and monitoring the activities, the movements, and the overall conditions of the assisted individuals as well as to assess their vital parameters (e.g., heart rate, respiratory rate). Similarly, audio sensors have the potential to become one of the most important modalities for interaction with AAL systems, as they can have a large range of sensing, do not require physical presence at a particular location and are physically intangible. Moreover, relevant information about individuals’ activities and health status can derive from processing audio signals (e.g., speech recordings). Nevertheless, as the other side of the coin, cameras and microphones are often perceived as the most intrusive technologies from the viewpoint of the privacy of the monitored individuals. This is due to the richness of the information these technologies convey and the intimate setting where they may be deployed. Solutions able to ensure privacy preservation by context and by design, as well as to ensure high legal and ethical standards are in high demand. After the review of the current state of play and the discussion in GoodBrother, we may claim that the first solutions in this direction are starting to appear in the literature. A multidisciplinary 4 debate among experts and stakeholders is paving the way towards AAL ensuring ergonomics, usability, acceptance and privacy preservation. The DIANA, PAAL, and VisuAAL projects are examples of this fresh approach. This report provides the reader with a review of the most recent advances in audio- and video-based monitoring technologies for AAL. It has been drafted as a collective effort of WG3 to supply an introduction to AAL, its evolution over time and its main functional and technological underpinnings. In this respect, the report contributes to the field with the outline of a new generation of ethical-aware AAL technologies and a proposal for a novel comprehensive taxonomy of AAL systems and applications. Moreover, the report allows non-technical readers to gather an overview of the main components of an AAL system and how these function and interact with the end-users. The report illustrates the state of the art of the most successful AAL applications and functions based on audio and video data, namely (i) lifelogging and self-monitoring, (ii) remote monitoring of vital signs, (iii) emotional state recognition, (iv) food intake monitoring, activity and behaviour recognition, (v) activity and personal assistance, (vi) gesture recognition, (vii) fall detection and prevention, (viii) mobility assessment and frailty recognition, and (ix) cognitive and motor rehabilitation. For these application scenarios, the report illustrates the state of play in terms of scientific advances, available products and research project. The open challenges are also highlighted. The report ends with an overview of the challenges, the hindrances and the opportunities posed by the uptake in real world settings of AAL technologies. In this respect, the report illustrates the current procedural and technological approaches to cope with acceptability, usability and trust in the AAL technology, by surveying strategies and approaches to co-design, to privacy preservation in video and audio data, to transparency and explainability in data processing, and to data transmission and communication. User acceptance and ethical considerations are also debated. Finally, the potentials coming from the silver economy are overviewed.publishedVersio

A Comparison of Body Composition Between Elite and Sub-elite Rugby Union Players: An Observational Study

Introduction: The assessment of body composition in athletes has become frequently used in practice as it is assumed to be an important determinant for athletic performance. Dual energy X-ray absorptiometry (DXA), a three-compartment model which assesses body composition in the form of bone mineral content, lean mass and fat mass, has quickly become the gold-standard measurement of body composition in athletic populations. The aim of this study was to compare body composition and anthropometric measurements between elite and national and development level rugby union players to examine if elite players possess more fat mass, muscle mass and bone content compared to national and development level players due to a higher participation level. Methods: Demographic (age) and basic anthropometric data (stature, mass) were collected in 56 male rugby players (n=38 elite and n=18 national and development). Body composition outcomes were assessed from total-body less head (TBLH) DXA scans (Lunar iDXA, GE Healthcare (Madison, WI) taken during the preseason. The chosen significance level was p = 0.05 and the confidence interval was 95%. Two-way ANOVA tests were used to identify potential significance between the elite and national and developmental players as well as between the two positional groups (forwards and backs). Results: The elite players were significantly older (24 vs 20 years; p=0.001) and displayed significantly greater amounts of trunk total mass (47.8 ± 6.8 vs 43.4 ± 4.8 kg; p = 0.005) compared to national and developmental players. Forwards possessed greater stature (190.1 ± 6.5 vs 180.3 ± 5.2 cm; p <0.001) and body mass (112.6 ± 15.3 vs 89.4 ± 8.2 kg; p<0.001) compared to backs. Forwards also have greater arm (14.3 ± 1.1 vs 11.7 ± 1.2 kg; p <0.001), leg (38.8 ± 3.5 vs 31.2 ± 3.4 kg; p <0.001), trunk (51.7 ± 4.7 vs 41.6 ± 3.7 kg; p <0.001) and TBLH (104.8 ± 8.1 vs 84.6 ± 8.0 kg; p <0.001) total mass. Forwards possessed greater lean mass in the arms (10.9 ± 1.5 kg; p <0.001), legs (28.5 ± 2.3 vs 24.2 ± 2.9 kg; p <0.001) trunk (36.6 ± 2.8 vs 32.8 ± 3.4 kg; p <0.001) and TBLH (76.2 ± 5.0 vs 66.5 ± 7.1 kg; p <0.001) regions. Forwards reported a greater difference in right leg (14.4 ± 1.1 vs 12.2 ± 15 kg; p <0.001) and left leg (14.1 ± 1.2 vs 11.9 ± 1.4 kg; p <0.001) lean mass. Forwards showed greater fat mass in the arms (18.5 ± 3.9 vs 14.7 ± 3.2 %; p <0.001), legs (21.7 ± 4.4 vs 17.4 ± 3.7 %; p <0.001), trunk (25.6 vs 6.2 vs 18.1 ± 4.5 %; p <0.001) and TBLH (23.2 ± 4.7 vs 17.4 ± 3.9 %; p <0.001) regions than backs. Forwards also reported greater TBLH bone mass (4.02 ± 0.44 vs 3.52 kg; p <0.001), BMD (1.56 vs 0.08 vs 1.46 ± 0.09 kg; p<0.001) and BMC (4.02 ± 0.44 vs 3.52 kg; p <0.001) than backs. Conclusion: Elite players were older and possessed greater trunk total mass compared to the national and developmental players. The lack of differences in terms of body composition between the elite and national and developmental groups was likely due to the high level of performance of the national level players as many were close to making the transition to the elite level. In terms of playing position, forwards were greater in stature and possessed more body mass than backs. Forwards were found to have greater amounts of arms, legs, trunk and TBLH total mass, lean mass and fat mass compared to backs. Forwards also showed greater differences in right and left leg lean mass than backs and greater TBLH bone mass, TBLH bone mineral density and content. These findings indicate that playing position may be a greater determinant of body composition than playing level