bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of muscle damage after a rugby match with special reference to tackle plays
Authors: Takarada Y 
Published: September 2003

Objective:To investigate blood indices of muscle damage after a competitive rugby match.Methods:Fifteen elite amateur rugby players volunteered to participate (mean (SE) age 26.6 (0.7) years, height 179.8 (1.0) cm, weight 87.4 (2.2) kg, and Vo2max58.5 (1.2) ml/kg/min). The study was conducted after two competitive matches during the 1999–2000 season. Plasma concentrations of lactate, potassium (K+), sodium (Na+), and myoglobin, and the activity of creatine kinase were measured before and after the matches. In addition, the number of tackles by and on each subject and the average duration of the work and rest periods were analysed using video recordings of the matches.Results:Myoglobin concentration and creatine kinase activity showed appreciable transient increases after the match. Peak values for myoglobin concentration (980 (166) μg/l) and creatine kinase activity (1081 (159) U/l) were observed 45 minutes and 24 hours after the match respectively. Positive and significant correlations were observed between the number of tackles and both peak myoglobin concentration (r= 0.85, p<0.01; n = 14) and peak creatine kinase activity (r= 0.92, p<0.01; n = 14). Plasma lactate and K+concentrations also showed appreciable increases after the match, whereas plasma Na+concentration showed a gradual decrease. The mean duration of the work and rest periods were 21.5 (2.2) and 24.3 (3.1) seconds respectively.Conclusions:The rugby matches resulted in serious structural damage to the muscles, the extent of which was highly dependent on the number of tackles.
Anthropometry of young competitive sport rock climbers
Authors: Watts P B , Joubert L M , Lish A K , Mast J D , Wilkins B 
Published: September 2003

Background:Adult elite competitive rock climbers are small in stature with low body mass and very low body fat percentage. These characteristics have generated concern that young climbers may attempt body mass reduction to extreme levels with adverse consequences for health and performance. No published anthropometry data for young competitive climbers exist.Objective:To describe the general anthropometric characteristics of junior US competitive rock climbers.Methods:Ninety subjects (mean (SD) age 13.5 (3.0) years) volunteered to participate. All competed at the Junior Competition Climbers Association US National Championship. Anthropometric variables, including height, mass, body mass index (BMI), arm span, biiliocristal and biacromial breadths, skinfold thickness at nine anatomical sites, forearm and hand volumes, and handgrip strength, were measured. Selected variables were expressed as ratio values and as normative age and sex matched centile scores where appropriate. A control group (n = 45) of non-climbing children and youths who participated in a variety of sports activities, including basketball, cross country running, cross country skiing, soccer, and swimming, underwent the same testing procedures in the Exercise Science Laboratory of Northern Michigan University.Results:Mean (SD) self reported climbing ability was 11.80 (1.20), or about 5.11d on the Yosemite decimal system scale. The mean (SD) experience level was 3.2 (1.9) years, and subjects competed in 10 (5) organised competitions over a 12 month period. Despite similarity in age, there were significant differences (p<0.01) between climbers and control subjects for height, mass, centile scores for height and mass, ratio of arm span to height (“ape index”), biiliocristal/biacromial ratio, sum of seven and sum of nine skinfolds, estimated body fat percentage, and handgrip/mass ratio. Despite significantly lower skinfold sums and estimated body fat percentage, no differences were found between climbers and controls for absolute BMI or BMI expressed as a centile score.Conclusions:Young competitive climbers have similar general anthropometric characteristics to elite adult climbers. These include relatively small stature, low body mass, low sums of skinfolds, and high handgrip to mass ratio. Relative to age matched athletic non-climbers, climbers appear to be more linear in body type with narrow shoulders relative to hips. Differences in body composition exist between climbers and non-climbing athletes despite similar BMI values.
Follow up exercise studies in paediatric obesity: implications for long term effectiveness
Authors: Maziekas M T , LeMura L M , Stoddard N M , Kaercher S , Martucci T 
Published: September 2003

Objectives:To examine the effects of exercise training on paediatric obesity immediately after training and at a one year follow up and to provide recommendations for future research.Methods:Studies that met the following criteria were included in a meta-analysis: (a) at least six subjects per group; (b) subject groups consisting of children in the 4–17 year age range; (c) pre-test and post-test values for body composition; (d) used exercise such as walking, jogging, cycle ergometry, high repetition resistance exercise, and combinations; (e) training programmes lasting eight weeks or more; (f) full length publications; (g) apparently healthy children.Results:A total of 135 studies of exercise as a method of treatment of paediatric obesity were located. Eight, containing 236 subjects, met our criteria for inclusion. Across all designs and categories, fixed effects modelling yielded significant decreases in the dependent variable percentage body fat immediately (0 = 1.04 (0.35); 95% confidence interval (CI) 0.41 to 1.6) and one year after the exercise intervention (0 = 0.84 (0.51); 95% CI 0.22 to 0.94). Forward stepwise linear regression suggested that the percentage body fat measured at the end of exercise training, exercise duration, and programme length accounted for 53–86% of the variance for percentage body fat at one year.Conclusions:These data indicate that exercise is efficacious for reducing percentage body fat in obese children and adolescents, and that exercise intervention may encourage long term maintenance of the observed gains.
Evaluation of shoulder internal rotator muscle strength in baseball players with physical signs of glenohumeral joint instability
Authors: Falla D L , Hess S , Richardson C 
Published: September 2003

Objectives:To identify whether subjects with glenohumeral translational instability present with a strength deficit in their internal rotator musculature, and therefore to determine if general strengthening exercises are warranted for the management of this condition.Methods:Eighteen male baseball players were allocated to two groups on the basis of expert clinical evaluation of the presence (n = 8) or absence (n = 10) of shoulder translational instability. A strain gauge was used to calculate the force generated during maximal isometric internal rotation contractions in neutral shoulder rotation and 30° of internal rotation.Results:The Mann-Whitney test identified no significant difference in force production during the maximum contractions in neutral rotation between the two subject groups. In the position of 30° shoulder internal rotation, subjects with glenohumeral translational instability produced significantly greater force than the control group (p<0.05).Conclusions:High load strength testing cannot be used as a diagnostic tool to identify people with glenohumeral instability. Similarly, heavy resistance strengthening exercises for the internal rotator musculature are not warranted during rehabilitation.
Effects of strenuous exercise on haemostasis: Table 1
Authors: Smith J E 
Published: September 2003

Objectives:To review the effects of exercise on haemostasis and examine the possible clinical sequelae of these changes.Methods:The search strategy included articles from 1966 to August 2002 using Medline and SportDiscus databases, and cross referencing the bibliographies of relevant papers.Results:Exercise results in activation of both the coagulation and fibrinolytic cascades, as shown by a reduction in whole blood clotting time and activated partial thromboplastin time, an increase in the activity of several components of the cascades, and an increase in fibrin degradation products. In vitro tests suggest that coagulation remains activated after fibrinolysis has returned to baseline levels.Conclusions:Both the coagulation and fibrinolytic cascades are stimulated by strenuous exercise, but the temporal relation between the two and its clinical significance remains to be clarified. Doctors and athletes should be aware of the haemostatic changes induced by exercise, and further work is needed to clarify the possible role of these changes in sudden cardiac death.
Sex differences in whole body skeletal muscle mass measured by magnetic resonance imaging and its distribution in young Japanese adults
Authors: Abe T , Kearns C F , Fukunaga T 
Published: September 2003

Objectives:To determine sex differences in the distribution of regional and total skeletal muscle (SM) using contiguous whole body magnetic resonance imaging (MRI) data, and to examine the relations between fat free mass (FFM) and total and regional SM masses.Methods:A total of 20 Japanese college students (10 women and 10 men) volunteered for the study. FFM was measured by two compartment densitometry. Whole body MRI images were prepared using a 1.5 T scanner. Contiguous transverse images with 1.0 cm slice thickness were obtained from the first cervical vertebra to the ankle joints. All MRI scans were segmented into four components (SM, subcutaneous adipose tissue, bone, and residual tissues). In each slice, the SM tissue cross sectional areas (CSAs) were digitised, and the muscle tissue volume per slice was calculated by multiplying muscle CSA by slice thickness. SM volume units (litres) were converted into mass units (kg) by multiplying the volumes by the assumed constant density (1.041 mg/ml) for SM.Results:The SM distribution pattern (shape of curve) from the contiguous whole body slices was essentially similar for the two sexes, with two large peaks and three smaller peaks (arms excluded). However, the largest peak was observed at the upper portion of the thigh for women and at the level of the shoulder for men. Men had larger (p<0.01) total and regional SM mass than women. All regional SM masses correlated highly (r= 0.90–0.99, p<0.01) with total SM mass. A strong positive correlation was observed between FFM and total and regional SM masses in both sexes (women,r= 0.95; men,r= 0.90; all p<0.01). As FFM increased, there was a corresponding increase in SM/FFM ratio for all subjects (r= 0.86, p<0.01).Conclusions:Sex differences in total SM/FFM ratio and regional SM distributions are associated with the degree of absolute FFM accumulation in men and women.
Body position affects performance in untrained cyclists
Authors: Ashe M C , Scroop G C , Frisken P I , Amery C A , Wilkins M A , Khan K M 
Published: September 2003

Objective:To compare cardiovascular and ventilatory variables in upright versus aero cycle ergometry at submaximal and maximal exercise intensities in untrained cyclists.Method:Ten physically active men (mean (SD) age 19.1 (1.10) years) who were unfamiliar with aerobars underwent maximal exercise testing and steady state cycling at 50, 100, and 150 W.Results:Participants had significantly greater maxima for oxygen uptake (Vo2), ventilation, heart rate, and workload maximum in the upright position. During steady state cycling at the three workloads, Vo2(ml/kg/min) and gross mechanical efficiency were significantly greater in the upright position.Conclusions:In untrained subjects performing with maximal effort, the upright position permits greater Vo2, ventilation, heart rate, and workload maxima. Further, in the steady state, exercise cycling may be less costly in the upright position. For this reason, untrained cyclists need to weigh body position effects against the well known aerodynamic advantages of the aero position.
Physical activity energy expenditure measured using a portable telemetric device in comparison with a mass spectrometer: Table 1
Authors: Maiolo C , Melchiorri G , Iacopino L , Masala S , De Lorenzo A 
Published: September 2003

Background:Several studies have evaluated the accuracy of portable metabolic gas analysis systems, which measure physical activity energy expenditure. Since the Cosmed K2 telemetric system, two K4 devices (RQ and b2) have been developed.Objective:To compare measurements using the Cosmed K4 RQ with measurements by a traditional method (mass spectrometer) for a sample of healthy subjects performing physical exercise of various intensities.Methods:Nine healthy male footballers (mean (SD) age 18.3 (2.2) years) performed an incremental exercise running test from 8 km/h to exhaustion, with an increase of 2 km/h for each level of the test protocol. The expired air was collected simultaneously using the Cosmed K4 RQ and Airspec QP9000 mass spectrometer. Oxygen consumption (Vo2) and carbon dioxide production (Vco2) were measured at rest and at each exercise intensity.Results:No significant differences were found between Vo2and Vco2measured by the two instruments, at rest or during exercise.Conclusions:The application of the Cosmed K4 RQ system for Vo2and Vco2measurements at rest and during both submaximal and maximal exercise may be of interest to sport physiologists, nutritionists, and doctors.
A 16 year study of injuries to professional kickboxers in the state of Victoria, Australia
Authors: Zazryn T R , Finch C F , McCrory P 
Published: September 2003

Objectives:To determine the rate and type of injuries occurring to registered professional kickboxers in Victoria, Australia over a 16 year period.Methods:Data describing all fight outcomes and injuries sustained during competition for the period August 1985 to August 2001 were obtained from the Victorian Professional Boxing and Combat Sports Board.Results:A total of 382 injuries were recorded from 3481 fight participations, at an injury rate of 109.7 injuries per 1000 fight participations. The most common body region injured was the head/neck/face (52.5%), followed by the lower extremities (39.8%). Specifically, injuries to the lower leg (23.3%), the face (19.4%), and intracranial injury (17.2%) were the most common. Over 64% of the injuries were superficial bruising or lacerations.Conclusion:The nature of kickboxing, whereby kicking the opponent is the prime movement and the head a prime target, is reflected in the distributions of body regions most commonly injured by participants. Further research into injury patterns in different styles of kickboxing and the mechanism of injury occurrence is required. Exposure adjusted prospective studies are needed to monitor injury rates over time.
Reflections on Real Presence by a Virtual Person
Authors: Heeter Carrie 
Published: September 2003

I have lived in San Francisco while working as a full-time virtual faculty member for Michigan State University for nearly six years. Unlike most humans, I spend a larger proportion of every day as a virtual person than as a physical person. This article is adapted from a keynote speech I delivered at the Fourth International Workshop on Presence in Philadelphia in May of 2001. I use a personal narrative style to explore issues and to question some of the research community's prevailing assumptions about presence. Lombard and Ditton's (1997) frequently cited conceptualization defines presence as a “perceptual illusion of nonmediation” that occurs “when a person fails to perceive or acknowledge the existence of a medium in his/her communication environment and responds as he/she would if the medium were not there.” The underlying assumption is that, in the absence of technology, everyone experiences continuous presence at a constant intensity throughout their lives. Instead, this article suggests that presence is not a constant of everyday nonmediated experience. Careful consideration of unmediated (real) presence might help the conceptualization and study of mediated presence.
Movement Behavior for Soldier Agents on a Virtual Battlefield
Authors: Reece Douglas A. 
Published: September 2003

We have developed a movement behavior model for soldier agents who populate a virtual battlefield environment. Whereas many simulations have addressed human movement behavior before, none of them has comprehensively addressed realistic military movement at individual and unit levels. To design an appropriate movement behavior model, we found it necessary to elaborate all of the requirements on movement from the military tasks of interest, define a behavior architecture that encompasses all required movement tasks, select appropriate movement planning and control approaches in light of the requirements, and implement the planning and control algorithms with novel enhancements to achieve satisfactory results. The breadth of requirements in this problem domain makes simple behavior architectures inadequate and prevents any single planning approach from easily accomplishing all tasks. In our behavior architecture, a hierarchy of tasks is distributed over unit leaders and unit members. For movement planning, we use an A* search algorithm on a hybrid search space comprising a two-dimensional regular grid and a topological map; the plan produced is a series of waypoints annotated with posture and speed changes. Individuals control movement with reactive steering behaviors. The result is a system that can realistically plan and execute a variety of unit and individual agent movement tasks on a virtual battlefield.
Bridging Nonliving and Living Matter
Authors: Rasmussen Steen , Chen Liaohai , Nilsson Martin , Abe Shigeaki 
Published: September 2003

Assembling non-biological materials (geomaterials) into a proto-organism constitutes a bridge between nonliving and living matter. In this article we present a simple step-by-step route to assemble a proto-organism. Many pictures have been proposed to describe this transition within the origins-of-life and artificial life communities, and more recently alternative pictures have been emerging from advances in nanoscience and biotechnology. The proposed proto-organism lends itself to both traditions and defines a new picture based on a simple idea: Given a set of required functionalities, minimize the physicochemical structures that support these functionalities, and make sure that all structures self-assemble and mutually enhance each other's existence. The result is the first concrete, rational design of a simple physicochemical system that integrates the key functionalities in a thermodynamically favorable manner as a lipid aggregate integrates proto-genes and a proto-metabolism. Under external pumping of free energy, the metabolic processes produce the required building blocks, and only specific gene sequences enhance the metabolic kinetics sufficiently for the whole system to survive. We propose an experimental implementation of the proto-organism with a discussion of our experimental results, together with relevant results produced by other experimental groups, and we specify what is still missing experimentally. Identifying the missing steps is just as important as providing the road map for the transition. We derive the kinetic and thermodynamic conditions of each of the proto-organism subsystems together with relevant theoretical and computational results about these subsystems. We present and discuss detailed 3D simulations of the lipid aggregation processes. From the reaction kinetics we derive analytical aggregate size distributions, and derive key properties of the metabolic efficiency and stability. Thermodynamics and kinetics of the ligation directed self-replication of the proto-genes is discussed, and we summarize the full life cycle of the proto-organism by comparing size, replication time, and energy with the biomass efficiency of contemporary unicells. Finally, we also compare our proto-organism picture with existing origins-of-life and protocell pictures. By assembling one possible bridge between nonliving and living matter we hope to provide a piece in the ancient puzzle about who we are and where we come from.
Frog and Cyberfrog are Friends: Dissection Simulation and Animal Advocacy
Authors: Fleischmann Kenneth 
Published: September 2003

AbstractAlthough at first glance it may seem an unlikely alliance, frogs and cyberfrogs certainly benefit from an unusual friendship that connects the virtual world of dissection simulation and the physical realm of nonhuman animal advocacy.This paper focuses on the symbiotic relationship of dissection simulation designers and animal advocates. Dissection simulation manufacturers benefit from this relationship through the purchasing and promotion of their products by animal advocacy organizations, and also they benefit from policy changes that encourage the use of dissection simulations as alternatives to dissection. Reciprocally,animal advocacy organizations benefit by saving animal lives, gaining a new tool for convincing teachers to stop dissecting, and demonstrating that they are a pro-technology movement. The knowledges and values embedded in cyberfrogs make them both boundary objects and cyborgs.
"What a Thing, then, is this Cow...": Positioning Domestic Livestock Animals in the Texts and Practices of Small-Scale "Self-Sufficiency"
Authors: Holloway Lewis 
Published: September 2003

AbstractThis paper focuses on the positioning of animals other than human in the texts and practices of two versions of small-scale food "self-sufficiency" in Britain. The paper discusses the writings of Cobbett (1822/1926, 1830/1985) and Seymour (1960s/1970s) on self-sufficiency, suggesting that livestock animals are central, in a number of ways, to the constitution of these modes of self-sufficiency. First, animals are situated in both the texts and in the practicing of self-sufficiency regarded as essential parts of the economies and ecologies of small-scale food production. Second, animals' parts in these authors' criticisms of wider social, economic and political conditions supplement their role in small-scale domestic food supply. Animals become associated with a morality of human behavior and lifestyle and are part of the broader social critiques that the writing and practicing of these modes of self-sufficiency imply. These historically and geographically specific versions of self-sufficiency are valuable in defining and enacting possible alternative modes of human-animal relation in the context of food production.
The Moral Reasoning of Believers in Animal Rights
Authors: Block Gary 
Published: September 2003

AbstractThis study evaluated the moral reasoning of 54 individuals who believed in the concept of nonhuman animal rights using a research tool based on Kohlberg's (1986) cognitive theory of moral development. Results for these primarily college and postgraduate-educated individuals suggest that people who believe in animal rights have equivalent or higher-level moral reasoning when compared to adult, education-matched, historical control groups.
Beyond Dominance and Affection: Living with Rabbits in Post-Humanist Households
Authors: Smith Julie Ann 
Published: September 2003

AbstractNearly 20 years age, Yi-Fu Tuan wrote his influential Dominance and Affection:The Making of Pets (1984), which argued that human affection for domestic animals is inseparable from dominance. Today, cultural critics persist in the view that companion animals are compromised, even degraded, because they are controlled by humans. The essay attempts to rethink the relationship between humans and companion animals beyond the freedom-dominance binary. It argues for a conceptual approach that defers confidant interpretation of animals while dramatically relaxing control of them within human settings. It suggests that this approach be called a "performance ethic" and offered the House Rabbit Society as a model.