Showing papers by "Roy J. Shephard published in 1990"

Exercise, fitness, and health: a consensus of current knowledge: proceedings of the International Conference on Exercise, fitness, and health, May 29-June 3, 1988, Toronto, Canada.

Abstract: Part I: Consensus Statement and Introductory Addresses. Part II: Assessment and Determinants of Physical Activity, Fitness, and Health. Part III: Human Adaptation to Physical Activity. Part IV: Physical Activity and Fitness in Disease. Part V: Physical Activity and Fitness in Growth, Reproductive Health, and Ageing. Part VI: The Risks of Exercising.

Use of Attitude-Behaviour Models in Exercise Promotion

Abstract: Many studies have adopted a theoretical attitude-behaviour framework for the analysis of exercise behaviour. The most popular models include the Health Belief Model, the Protection Motivation Theory, the Social Cognitive Theory, the Theory of Reasoned Action, the Theory of Interpersonal Behaviour, and the Theory of Planned Behaviour. Aspects other than a preoccupation with health often have a strong influence upon an individual’s decision whether or not to engage in exercise. Expectations of self-efficacy, attitudes towards exercising (the affective dimension), perceived barriers to exercise, and past behaviour exert strong influences upon behavioural intention, which in turn influences overt behaviour. In some instances, the variables explaining intention also exert a direct influence upon behaviour in parallel with their influence upon intention. Those promoting exercise behaviour should focus initial attention upon the habit of exercising rather than upon the development of traditional ‘endurance fitness’.

The scientific basis of exercise prescribing for the very old.

Abstract: lder people are heterogeneous in physical ability. Calendar age offers some basis for categorization, but a functional classification 0 is more useful. We may recognize the youngold, with no restriction of physical activity, the middleold, with a slight limitation, and the very old or old-old, who face severe limitations.' In one study 80% of a North American sample of people at 65 years of age move without difficulty, but by the age of 80 years a high proportion are limited by cardiac or mental problems.2 Death is usually preceeded by eight to 10 years with some disability and about a year of total depend e n ~ y . ~ This brief review will discuss why the middleold and very old should exercise, what forms of exercise should be prescribed, and the likely physiological and psychological responses to such training.

On the generality of the "sit and reach" test: an analysis of flexibility data for an aging population.

Abstract: Head rotation, shoulder extension and rotation, ankle plantar and dorsiflexion, hip flexion, and sit and reach (SR) scores were examined in 41 women and 39 men, aged 45–75 years. The SR gave more reproducible data than the other measurements (intraclass test/retest correlation over 8 months, r = .83). SR scores were independent of standing height (r 2 = .068) but were greater in women (p < .002). The flexibility at all joints was less than reported for young adults. There were age-related decreases of flexibility scores for the head and shoulder joints (p < .01), with a parallel trend (p < .05) for ankle plantar flexion and SR scores (the last only after inclusion of an age-gender interaction term). A principal components analysis identified three factors (tentatively identified as general trunk, ankle, and shoulder flexibility) accounting for 55.9% of total variance. SR scores had a moderate correlation with the first factor (r = .61) but only weak correlations with the second and third. Althoug...

Fitness in special populations

Abstract: Normal Human Responses to Exercise and Training. An Historical View. Disability Classification. Fitness Assessment. Current Fitness Status. Training Programs. Biomechanical Factors, Wheelchair Design, and Injury Prevention. Personality, Behaviour, and Social Adjustment. Effective Program Design. A World View.

Strength training for wheelchair users

Abstract: Sedentary adult males with spinal lesions, all habitual wheelchair users, were allocated to exercise (n = 11) and control (n = 4) groups. A Cybex II dynamometer was used to assess peak power, average power, total work and muscular endurance for elbow flexion/extension, shoulder flexion/extension and shoulder abduction/adduction at five angular velocities, on recruitment and after eight and 16 weeks of forearm ergometer training (three days/week). Small sub-groups of the exercised subjects were assigned to high or low intensity endurance effort (70 or 40 per cent of maximal oxygen intake) and long or short training sessions (40 or 20 minutes per session). Despite the aerobic nature of the activity, gains of average power were registered by the two muscle groups most involved in the ergometer task (shoulder extension and elbow flexion). In keeping with current theories of training, gains were largest with prolonged, high intensity activity at angular velocities approximating those adopted during training.

Physical activity and cancer.

Abstract: Evidence that physical activity may protect against various forms of cancer is examined in relation to occupational demands, leisure activities and participation in sport while at university. The variety of forms of neoplasm and equally varied physical activity histories militate against finding any simple relationship between the risk of malignancy and the individual's physical activity history. Nevertheless, five of seven major occupational studies suggest that a physically active occupation offers some protection against colon cancer, and an application of Bradford Hill's criteria generally supports the causal nature of the relationship between physical inactivity and an increased risk of intestinal neoplasia. However, existing reports are by no means conclusive; there thus remains a need for well-designed epidemiological studies of this issue. Data from one laboratory also suggest that in women a history of active leisure is associated with a reduced prevalence of breast and reproductive system cancers. Physical activity potentially encourages a healthy lifestyle, and it could have more direct effects on certain forms of carcinogenesis (for instance, by a speeding of gastro-intestinal transit, or a moderation of sex hormone levels). However, there are also potential negative effects from some types of exercise, particularly an excessive exposure to ultra-violet light in certain water sports. Since moderate exercise elevates mood and helps to conserve lean tissue, it may finally be a helpful component of treatment after a neoplasm has been diagnosed.

An evaluation of the potential role of the physician in influencing community exercise behavior.

Abstract: The potential influence of physicians upon the exercise behavior of individuals has been examined. Key questions explored were a) whether people believed that their personal physician thought that ...

Can Regular Sports Participation Slow the Aging Process? Data on Masters Athletes.

Abstract: In brief: Even moderate sports participation is associated with enhanced functional capacity, according to data collected on 554 men and 202 women who underwent maximal exercise testing during the 1985 World Masters Games in Toronto. Their training was modest relative to elite competitors. Nevertheless, their peak power output during cycle ergometry and peak oxygen intake were above the norm for nonathletes of the same age, resembling the values of sedentary 25-year-olds. Such gains have major implications for maintaining independence in the later years of life. Thus encouraging older people to increase their physical activity would seem an important public health measure.

The Biology and Medicine of Sailing

Abstract: The physiological demands of sailing are highly specific, varying with wind conditions, type of craft, and crew position. In a light wind, the only physiological variable yet shown to influence performance is the resting blood sugar. Under high wind conditions, the skipper should be light ( 80kg). Height does not seem a great advantage to crew, possibly because they then lack the muscular strength to exploit the added leverage. Muscle strength, endurance and a tolerance of anaerobic metabolism are all desirable attributes of crew, and competitive performance can be improved by a winter training programme that develops these aspects of muscle performance in the abdominal and thigh regions. The skipper must meet intense and prolonged cerebral demands in the face of periodic isometric work; performance may thus be helped by ingestion of carbohydrate over the course of a race. The ability to sustain isometric contractions in the ‘hiking’ position may also be improved if the muscles are preloaded with glycogen. The combination of a heavy body build, above average age for an athlete and sustained isometric contraction probably makes the yachting enthusiast vulnerable to ischaemic heart disease. Advisors to a sailing team must further take account of the risks presented by immersion in cold water, loss of sleep, circadian variations of performance over an event, and problems of motion sickness in rough weather.

Assessment of occupational fitness in the context of human rights legislation.

Abstract: The potential applications of occupational fitness assessment are briefly reviewed in the general context of recent human rights legislation. Limiting tasks in an industrial process must be examined, and bona fide occupational requirements must be defined in terms of psychomotor ability and physiological capacity. Heavy work may demand a high level of aerobic power, muscular strength, or tolerance of adverse environments. Such criteria can define an action limit, above which the task must be redesigned, or workers must be specially selected and trained. The courts may accept the results of field performance tests more readily than laboratory measurements of aerobic power or muscular strength. However, neither type of test currently has the reliability and validity needed to characterize the individual, or to distinguish a good worker from a poor worker. If the concern is public safety, employment must thus be based upon average data for a given population, while if the concern is employment equity, the only recourse seems a probationary period of employment.

Meeting carbohydrate and fluid needs in soccer.

Abstract: If a hard game of soccer is played under warm conditions, there are conflicting demands for carbohydrate and for fluid replenishment, with both variables having a potential influence upon competitive performance. The present review examines evidence concerning the extent of carbohydrate depletion during soccer play, its potential impact upon play, and the optimum choice of beverage for minimizing physiological problems. Players should be prepared for competition by eating a good mixed diet; this should assure a daily intake of at least 8 g of carbohydrate per kilogram of body mass. Although theoretical arguments favour the use of glucose/polymer drinks, in practice, these do not offer any great advantage relative to water or a dilute glucose solution. Some 500 mL of water or a low-concentration carbohydrate preparation can usefully be drunk in the thirty minutes immediately prior to a game, with a further 500 mL drink of the same fluid being taken at half time. During the recovery period following a soccer match, it is useful to increase the salt content of meals, and again to provide a good mixed diet with an emphasis upon carbohydrates.

Measuring Physical Activity in the Elderly: Some Implications for Nutrition

Abstract: RÉSUMÉ Les méthodes possibles de mesurer l'activité physique comprennent une évaluation d'attitude, le complètement des questionnaires, l'utilisation des moniteurs personnels et la détermination de capacité physique. L'évaluation des sujets âgés présente quelques problèmes spécifiques. L'attitudé face à l'activité physique indique l'intention de l'individu de faire l'exercice, mais quelques barrières pratiques peuvent limiter l'expression de cette intention. Un questionnaire reste ouvert à une tendance d'exagérer l'activité physique, mais néanmoins, cela semble la façon la plus pratique d'évaluer une population importante. L'application des moniteurs personnels se limite aux échantillons assez limités, mais cette technologie peut apporter l'information conduisante à une amélioration progressive des questionnaires. Des épreuves de capacité physique sont influencées par les facteurs génétiques et peuvent favoriser un selectionnement de sujets actifs. Les mesures directes d'activité physique manquent de précision, mais peuvent identifier quelques sujets qui méritent une évaluation nutritive détaillée. Le développement des méthodes d'évaluation de l'activité physique peut enfin encourager une augmentation de l'activité habituelle de la part des sujets âgés. ABSTRACT The possibility of measuring human activity patterns is discussed in terms of data obtained by attitude assessment, activity questionnaires, personal monitoring devices and fitness assessment. Specific problems are noted in applying these several techniques to elderly populations. Attitude assessments indicate the intention to exercise, and practical barriers may limit the translation of intention into overt behaviour. Questionnaires are open to exaggeration, but nevertheless remain the most practical method of evaluating large populations. Personal monitors can only be applied to small samples, but may nevertheless be helpful in improving questionnaire design. Fitness tests raise concerns of safety, and seem likely to bias population sampling towards the active elderly; scores are also influenced more by inherited factors than by current activity. Activity measurements seem unlikely to yield more than a crude estimate of total dietary needs in a population, but they may nevertheless help to identify a subset of old people where detailed nutritional examination is particularly cost-effective. The accurate determination of activity patterns will also have value as a means of encouraging the elderly to adopt an active lifestyle, maximizing their physical potential.

Body composition in biological anthropology.

Abstract: Preface 1. Introduction 2. Epidemiological indices, anthropometric and cadaver estimates of body composition 3. Determination of body fat 4. Determination of body water 5. Determination of lean tissue 6. Estimation of bone mass 7. Regional differences of body composition 8. Developmental changes, growth and aging 9. Genetic influences upon body composition 10. Environmental influences 11. Pathological disturbances of body composition 12. Human adaptability and body composition Glossary References Index.

Influence of age, time since infarction and angina upon the cardiovascular response to physical training

Abstract: Variability in the response to “post‐coronary”; exercise rehabilitation has previously been attributed to the age of the patient, their date of entry to the program relative to the acute incident, and the liability of the participant to anginal pain We examined the relative importance of these three variables in a sample of thirty‐five patients seen two to 12 months after a well‐defined myocardial infarction Cardiovascular responses of the patients at entry to the program and after six months and one year of intensive endurance training were evaluated by a progressive submaximal cycle ergometer test Cardiac output was determined by a carbon dioxide rebreathing method Training responses of the eight subgroups of patients was remarkably uniform; over the 12 months of observation, all showed an increase of stroke volume and a decrease of heart rate during submaximal work The corresponding increase of predicted maximal oxygen intake ranged from 13 to 21% We conclude that the variable cardiac response to