A study on matching and multi-objective fuzzy control strategy of heavy truck suspension system

Matching method of heavy truck-rear air suspensions is discussed, and a fuzzy control strategy which improves both ride comfort and road friendliness of truck by adjusting damping coefficients of the suspension system is found. In the first place, a Dongfeng EQ1141G7DJ heavy truck’s ten DOF whole vehicle-road model was set up based on Matlab/Simulink and vehicle dynamics. Then appropriate passive air suspensions were chosen to replace the original rear leaf springs of the truck according to truck-suspension matching criterions, consequently, the stiffness of front leaf springs were adjusted too. Then the semi-active fuzzy controllers were designed for further enhancement of the truck’s ride comfort and the road friendliness. After the application of semi-active fuzzy control strategy through simulation, is was indicated that both ride comfort and road friendliness could be enhanced effectively under various road conditions. The strategy proposed may provide theory basis for design and development of truck suspension system in China.

Determining heavy vehicle suspension health from vibratory wheel loads

A low-cost test bed was made from a modified heavy vehicle (HV) brake tester. By rotating a test HV’s wheel on an eccentric roller, a known vibration was imparted to the wheel under test. A control case for dampers in good condition was compared with two test cases of ineffective shock absorbers. Measurement of the forces at the bearings of the roller provided an indication of the HV wheel-forces. Where the level of serviceability of the shock absorbers varied, differences in wheel load provided a quality indicator corresponding to a change of damper characteristic. Conclusions regarding the levels of damper maintenance beyond which HV suspensions cause road damage and dynamic wheel forces at the threshold of tyre wear at which HV shock absorbers are normally replaced are presented.

Ecological approaches to cognition and action in sport and exercise : ask not only what you do, but where you do it

In recent decades, concepts and ideas from James J. Gibson’s theory of direct perception in ecological psychology have been applied to the study of how perception and action regulate sport performance. This article examines the influence of different streams of thought in ecological psychology for studying cognition and action in the diverse behavioural contexts of sport and exercise. In discussing the origins of ecological psychology it can be concluded that psychologists such as Lewin, and to some extent Heider, provided the initial impetus for the development of key ideas. We argue that the papers in this special issue clarify that the different schools of thinking in ecological psychology have much to contribute to theoretical and practical developments in sport and exercise psychology. For example, Gibson emphasized and formalized how the individual is coupled with the environment; Brunswik raised the issue of the ontology of probability in human behaviour and the problem of representative design for experimental task constraints; Barker looked carefully into extra-individual behavioural contexts and Bronfenbrenner presented insights pertinent to the relations between behaviour contexts, and macro influences on behaviour. In this overview, we highlight essential issues from the main schools of thought of relevance to the contexts of sport and exercise, and we consider some potential theoretical linkages with dynamical systems theory.

Difference-based meta-analytic procedures for between-participant and/or within-participant designs : a tutorial review for sports and exercise scientists

The aim of this paper is to provide a contemporary summary of statistical and non-statistical meta-analytic procedures that have relevance to the type of experimental designs often used by sport scientists when examining differences/change in dependent measure(s) as a result of one or more independent manipulation(s). Using worked examples from studies on observational learning in the motor behaviour literature, we adopt a random effects model and give a detailed explanation of the statistical procedures for the three types of raw score difference-based analyses applicable to between-participant, within-participant, and mixed-participant designs. Major merits and concerns associated with these quantitative procedures are identified and agreed methods are reported for minimizing biased outcomes, such as those for dealing with multiple dependent measures from single studies, design variation across studies, different metrics (i.e. raw scores and difference scores), and variations in sample size. To complement the worked examples, we summarize the general considerations required when conducting and reporting a meta-analysis, including how to deal with publication bias, what information to present regarding the primary studies, and approaches for dealing with outliers. By bringing together these statistical and non-statistical meta-analytic procedures, we provide the tools required to clarify understanding of key concepts and principles.

Australian Association for Exercise and Sport Science position stand : optimising cancer outcomes through exercise

Cancer represents a major public health concern in Australia. Causes of cancer are multifactorial with lack of physical activity being considered one of the known risk factors, particularly for breast and colorectal cancers. Participating in exercise has also been associated with benefits during and following treatment for cancer, including improvements in psychosocial and physical outcomes, as well as better compliance with treatment regimens, reduced impact of disease symptoms and treatment-related side effects, and survival benefits for particular cancers. The general exercise prescription for people undertaking or having completed cancer treatment is of low to moderate intensity, regular frequency (3-5 times/week) for at least 20 minutes per session, involving aerobic, resistance or mixed exercise types. Future work needs to push the boundaries of this exercise prescription, so that we can better understand what constitutes optimal, desirable and necessary frequency, duration, intensity and type, and how specific characteristics of the individual (e.g., age, cancer type, treatment, presence of specific symptoms) influence this prescription. What follows is a summary of the cancer and exercise literature, in particular the purpose of exercise following diagnosis of cancer, the potential benefits derived by cancer patients and survivors from participating in exercise programs, and exercise prescription guidelines and contraindications or considerations for exercise prescription with this special population. This report represents the position stand of the Australian Association of Exercise and Sport Science on exercise and cancer recovery and has the purpose of guiding Accredited Exercise Physiologists in their work with cancer patients.

Exercise and secondary lymphedema : safety, potential benefits, and research issues

Participating in regular physical activity is encouraged following breast cancer (BC) treatment, except for those who have subsequently developed lymphoedema. We designed a randomised controlled trial to investigate the effect of participating in a supervised, mixed-type, moderate-intensity exercise program among women with lymphoedema following breast cancer. Women <76 years who had completed BC treatment at least six months prior and subsequently developed unilateral, upper-limb lymphoedema were randomly allocated to an intervention (n=16) or control (n=16) group. The intervention group (IG) participated in 20 supervised group exercise sessions over 12 weeks, while the control group (CG) was instructed to continue habitual activities. Lymphoedema status was assessed by bioimpedance spectroscopy (impedance ratio between limbs) and perometry (volume difference between limbs). Mean baseline measures were similar for the IG (1.13+0.15 and 337+307ml, respectively) and CG (1.13+0.15 and 377+416ml, respectively) and no changes were observed over time. However, 2 women in the IG no longer had evidence of lymphoedema by study end. Average attendance was over 70% of supervised sessions, and there were no withdrawals. The results indicate that, at worst, exercise does not exacerbate secondary lymphoedema. Women with secondary lymphoedema should be encouraged to be physically active, optimising their physical and psychosocial recovery.

Exercise for health : a breast cancer recovery program - quality of life benefits [Conference Abstract]

Introduction: Five-year survival from breast cancer in Australia is 87%. Hence, ensuring a good quality of life (QOL) has become a focal point of cancer research and clinical interest. Exercise during and after treatment has been identified as a potential strategy to optimise QOL of women diagnosed with breast cancer.----- Methods: Exercise for Health is a randomised controlled trial of an eight-month, exercise intervention delivered by Exercise Physiologists. An objective of this study was to assess the impact of the exercise program during and following treatment on QOL. Queensland women diagnosed with unilateral breast cancer in 2006/07 were eligible to participate. Those living in urban-Brisbane (n=194) were allocated to either the face-to-face exercise group, the telephone exercise group, or the usual-care group, and those living in rural Queensland (n=143) were allocated to the telephone exercise group or the usual-care group. QOL, as assessed by the Functional Assessment of Cancer Therapy-Breast (FACT-B+4) questionnaire, was measured at 4-6 weeks (pre-intervention), 6 months (mid-intervention) and 12 months (three months post-intervention) post-surgery.----- Results: Significant (P<0.01) increases in QOL were observed between pre-intervention and three months post-intervention 12 months post-surgery for all women. Women in the exercise groups experienced greater mean positive changes in QOL during this time (+10 points) compared with the usual-care groups (+5 to +7 points) after adjusting for baseline QOL. Although all groups experienced an overall increase in QOL, approximately 20% of urban and rural women in the usual-care groups reported a decline in QOL, compared with 10% of women in the exercise groups.----- Conclusions: This work highlights the potential importance of participating in physical activity to optimise QOL following a diagnosis of breast cancer. Results suggest that the telephone may be an effective medium for delivering exercise counselling to newly diagnosed breast cancer patients.

Preliminary Results from Exercise for Health : A Breast Cancer Recovery Project [Abstract]

The Exercise for Health program is a telephone-delivered exercise intervention for women with breast cancer (BC) living in regional Queensland. The effect of the program is being evaluated in the context of a randomised controlled trial. Consenting, newly diagnosed BC patients, treated in one of 8 regional Queensland hospitals, were randomly allocated to telephone-based exercise counselling (EC) or usual care (UC) at 6-weeks post-surgery. EC participants received an exercise workbook and 16 calls from an exercise physiologist over 8 months. Physical activity levels (PA) (Active Australia & CHAMPS), quality-of-life (FACTB+4), upper-body function (DASH) and fatigue (FACIT-Fatigue) were assessed at baseline (4-6 weeks post-surgery), 6- and 12-months post-surgery. Preliminary analyses of available 6-month data were conducted using t-tests and repeated measures ANCOVAs. Participating women (n=143; EC n=73, UC n=70) were aged 53±9 years and 30% met PA guidelines at baseline. Up to two thirds of the women received adjuvant therapy during the first 6 months following surgery. Greater improvements (mean change+SD) occurred for the EC vs UC group in weekly sessions of walking (1.83±4.3 vs -0.5±5.5, p=0.029) moderate-vigorous PA (5.0±6.5 vs -1.1±6.1, p=0.005) and strength training (1.9±2.9 vs -0.5±4.2 p<0.001), and in upper-body function, reflected by lower log-transformed disability scores (-0.34±0.44 vs -0.17±0.28, p=0.038). More EC than UC participants met PA guidelines at 6 months (46.3% vs 32.7%). Preliminary findings from this ongoing trial suggest that the telephone is a feasible and effective medium for delivering exercise counselling to newly diagnosed BC patients living in regional areas.

Recovery and exercise interventions following breast cancer [Abstract]

Over 13,000 women are diagnosed with breast cancer each year in Australia and approximately 90% of these women will survive longer than 5-years. However, survival following treatment for breast cancer is often associated with adverse physical and psychosocial side effects, which persist beyond treatment cessation. As incidence and survival rates associated with breast cancer continue to rise, there is an imperative need to understand the extent of treatment-related concerns and ways in which these concerns can be minimized and/or overcome. A growing body of scientific evidence demonstrates that extensive quality of life benefits can be attained through exercise during and following breast cancer treatment. Such benefits observed include improvements in psychosocial and physical outcomes, as well as better compliance with treatment regimens and reduced impact of disease symptoms and treatment-related side effects. There is also evidence to suggest that post-diagnosis physical activity can improve survival. However, the majority of women newly diagnosed with breast cancer in Australia are not sufficiently active and the majority experience further declines in their physical activity levels during treatment. Throughout the course of this presentation, which draws on data from cohort studies and randomized trials of exercise interventions conducted in Queensland, the potential benefits of exercising during and following breast cancer treatment, the exercise prescription recommended for breast cancer survivors, the limits of our evidence-based knowledge and the issues faced by clinicians and patients with respect to exercise following a cancer diagnosis will be discussed. The question is no longer whether people with breast cancer should be active during and following their treatment, but is how do health care professionals best assist people to become and stay active in an endeavor to live healthy lives beyond their cancer experience.

Exercise and cancer recovery workshop

Cancer represents a major public health concern in Australia, with 100,000 new cancer cases diagnosed each year. Physical activity level (specifically lack of physical activity) is considered a known risk factor, particularly for breast and colorectal cancers. Physical activity also plays a role following a cancer diagnosis; being regularly active during and following treatment for cancer has been associated with improvements in psychosocial and physical outcomes, as well as better compliance with treatment regimens, reduced impact of disease symptoms and treatment-related side effects, and survival benefits for particular cancers. This workshop will provide an overview of the work presented in the recently published AAESS position stand on exercise and cancer recovery. A summary of the cancer and exercise literature, in particular the purpose of exercise following diagnosis of cancer, the potential benefits derived by cancer patients and survivors from participating in exercise programs, and exercise prescription guidelines and contraindications or considerations for exercise prescription with this special population, will be given. A case summary will also be presented and discussed.

Exercise and lymphoedema : Is it good or bad?

Being physically active during and following treatment for breast cancer has been associated with a range of benefits including improved fitness and function, body composition and immune function and reductions in stress, depression and anxiety, as well as the number and severity of treatment-related side-effects such as nausea, fatigue and pain, all of which contribute to improvements in quality of life. There is also emerging evidence linking active lifestyles with improved survival. Therefore, there is little doubt that participating in regular exercise following breast cancer is ‘good’. Unfortunately, research investigating the role of exercise for women considered at high-risk of lymphoedema or who have developed lymphedema following breast cancer is lacking. For fear of initiating or exacerbating lymphoedema, these women have traditionally been cautioned rather than encouraged to be regularly active. However, recent preliminary findings suggest that being inactive may increase risk of developing lymphedema, and that for those with lymphoedema, participation in an exercise program does not exacerbate the condition. This presentation will address what we know about the role of exercise following a breast cancer diagnosis and will provide some practical recommendations about becoming and staying regularly active following breast cancer, for those with and without lymphoedema.

Exercise and activity – how it helps lymphoedema?

Research investigating the role of exercise in the prevention and/or management of lymphoedema is lacking. For fear of initiating or exacerbating lymphoedema, and its associated symptoms, those with lymphoedema have traditionally been cautioned against engaging in physical activity rather than encouraged to be regularly active. However, recent preliminary findings suggest that being inactive may increase risk of developing lymphedema, and that for those with lymphoedema, participation in an exercise program does not exacerbate the condition. This presentation will address why engaging in regular physical activity is important, what we know about the role of exercise with respect to lymphoedema prevention and management, and will provide some practical recommendations about becoming and staying regularly active for those with lymphoedema.

Age-related differences in exercise and quality of life among breast cancer survivors

Purpose: Physical activity has become a focus of cancer recovery research as it has the potential to reduce treatment-related burden and optimize health-related quality of life (HRQoL). However, the potential for physical activity to influence recovery may be age-dependent. This paper describes physical activity levels and HRQoL among younger and older women after surgery for breast cancer and explores the correlates of physical inactivity. Methods: A population-based sample of breast cancer patients diagnosed in South-East Queensland, Australia, (n=287) were assessed once every three months, from 6 to 18 months post-surgery. The Functional Assessment of Cancer Therapy-Breast questionnaire (FACTB+4) and items from the Behavioral Risk Factor Surveillance System (BRFSS) questionnaire were used to measure HRQoL and physical activity, respectively. Physical activity was assigned metabolic equivalent task (MET) values, and categorized as < 3, 3 to 17.9 and 18+ MET-hours/weeks. Descriptive statistics, generalized linear models with age stratification (<50 years versus 50+ years), and logistic regression were used for analyses (p=0.05, two-tailed). Results: Younger women who engaged in 3 or more MET-hours/week of physical activity reported a higher HRQoL at 18 months compared to their more sedentary counterparts (p<0.05). Older women reported similar HRQoL irrespective of activity level and consistently reported clinically higher HRQoL than younger women. Increasing age, being overweight or obese, and restricting use of the treated side at six months post-surgery increased the likelihood of sedentary behavior (OR>3, p<0.05). Conclusions: Age influences the potential to observe HRQoL benefits related to physical activity participation. These results also provide relevant information for the design of exercise interventions for breast cancer survivors and highlights that some groups of women are at greater risk of long-term sedentary behavior.

Role of exercise in the prevention and management of lymphedema after breast cancer

Swelling or lymphedema of the limb, trunk, or breast is considered the most problematic and dreaded concern after treatment for breast cancer and has significant physical, psychological, and social ramifications. Conservative incidence estimates suggest that 20%-30% of breast cancer survivors will experience lymphedema, with the majority of cases (up to 80%) occurring within the first year after surgery. The etiology of secondary lymphedema seems to be multifactorial, with acquired abnormalities as well as preexisting conditions being contributory factors.

Beneficial effects of exercise : shifting the focus from body weight to other markers of health

Background: Exercise is widely promoted as a method of weight management, while the other health benefits are often ignored. The purpose of this study was to examine whether exercise-induced improvements in health are influenced by changes in body weight. Methods: Fifty-eight sedentary overweight/obese men and women (BMI 31.8 (SD 4.5) kg/m2) participated in a 12-week supervised aerobic exercise intervention (70% heart rate max, five times a week, 500 kcal per session). Body composition, anthropometric parameters, aerobic capacity, blood pressure and acute psychological response to exercise were measured at weeks 0 and 12. Results: The mean reduction in body weight was −3.3 (3.63) kg (p<0.01). However, 26 of the 58 participants failed to attain the predicted weight loss estimated from individuals’ exercise-induced energy expenditure. Their mean weight loss was only −0.9 (1.8) kg (p<0.01). Despite attaining a lower-than-predicted weight reduction, these individuals experienced significant increases in aerobic capacity (6.3 (6.0) ml/kg/min; p<0.01), and a decreased systolic (−6.00 (11.5) mm Hg; p<0.05) and diastolic blood pressure (−3.9 (5.8) mm Hg; p<0.01), waist circumference (−3.7 (2.7) cm; p<0.01) and resting heart rate (−4.8 (8.9) bpm, p<0.001). In addition, these individuals experienced an acute exercise-induced increase in positive mood. Conclusions: These data demonstrate that significant and meaningful health benefits can be achieved even in the presence of lower-than-expected exercise-induced weight loss. A less successful reduction in body weight does not undermine the beneficial effects of aerobic exercise. From a public health perspective, exercise should be encouraged and the emphasis on weight loss reduced.