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PubMed2003

Feasibility, physical capacity, and health benefits of a multidimensional exercise program for cancer patients undergoing chemotherapy.

Cancer patients frequently experience considerable loss of physical capacity and general wellbeing when diagnosed and treated for their disease. The aim of this study was to evaluate the feasibility, physical capacity, and health benefits of a multidimensional exercise program for cancer patients during advanced stages of disease who are undergoing adjuvant or high-dose chemotherapy. The supervised program included high- and low-intensity activities (physical exercise, relaxation, massage, and body-awareness training). A total of 23 patients between 18 and 65 years of age (median 40 years) participated in groups of seven to nine patients for 9 h weekly for 6 weeks. Physical capacity in terms of repetition maximum (RM) and maximal oxygen uptake (VO(2)max), physical activity level and psychosocial wellbeing (EORTC QLQ-C30, SF-36, HAD) were compared prior to and after completion of the program. The program was safe and well tolerated. The completion rate was 85.2%. Highly significant increases in physical capacity (1RM, VO(2)max) and an improved level of physical activity were achieved. Quality of life and general wellbeing assessments indicated improvements in several measures, but without reaching significance. It is concluded that an exercise program, which combines high- and low-intensity physical activities, may be used to prevent and/or minimize physical inactivity, fatigue, muscle wasting and energy loss in cancer patients undergoing chemotherapy.

Activities of Daily Living↗
PubMed2005

Physical activity levels of children who walk, cycle, or are driven to school.

BACKGROUND: Active commuting to school by walking or bicycle is widely promoted to increase children's physical activity. However, there is little data to describe the impact that travel mode, and in particular cycling, may have on activity levels. METHODS: Primary school children wore an accelerometer recording minute-by-minute physical activity, and completed questions describing travel habits. Total volume of physical activity and hourly physical activity patterns were estimated and groups of children compared by mode of travel to school. Data were collected as part of the European Youth Heart Study. RESULTS: A total of 332 children (average age 9.7 years, standard deviation [SD] = 0.4 years) completed all measurements. Children who walked to school were significantly more physically active than those who traveled by car (accelerometer counts per minute [cpm]: 667.7, SD = 233.7 vs 557.3, SD = 191.4; p = 0.01). Those who cycled to school recorded higher accelerometer counts than those who traveled by car, but differences were not significant. Boys who walked or cycled to school were significantly more physically active than those traveling by car (walk: 732.2 cpm, SD = 253.1 vs 592.8 cpm, SD = 193.9; p=0.007; cycle: 712.6 cpm, SD = 249.1 vs 592.8 cpm, SD = 193.9; p = 0.013). In girls, walking but not cycling to school was significantly associated with higher daily physical activity levels (606.3 cpm, SD = 197.7, vs 523.4 cpm, SD = 185.0 cpm; p = 0.05). CONCLUSIONS: In primary school-aged children, walking to school is associated with higher levels of overall physical activity compared with those who travel to school by motorized transport. Cycling is associated with higher overall physical activity only in boys.

Anthropometry↗
PubMed2004

A prehabilitation program for the prevention of functional decline: effect on higher-level physical function.

OBJECTIVE: To determine whether a home-based physical therapy (PT) program prevented decline in several higher-level measures of physical function among physically frail, community-living older persons. DESIGN: Randomized controlled trial. SETTING: General community. PARTICIPANTS: Persons (N=188) who were physically frail and aged 75 years or older. INTERVENTION: A home-based PT program (ie, prehabilitation) that focused primarily on improving underlying impairments in physical capabilities. MAIN OUTCOME MEASURES: Self-reported instrumental activities of daily living (IADLs); mobility, as determined by a modified version of the Performance Oriented Mobility Assessment; timed rapid gait and timed chair stands; and integrated physical performance, as determined by a modified version of the Physical Performance Test, were assessed at baseline, 7 months, and 12 months. RESULTS: As compared with participants in the educational control group, participants in the intervention group had reductions in IADL disability of 17.7% at 7 months (P=.036) and 12.0% at 12 months (P=.143) and had gains, ranging from 7.2% to 15.6%, in mobility and integrated physical performance at 7 and 12 months. CONCLUSIONS: Our home-based prehabilitation program offered modest but consistent benefits for the prevention of decline in several higher-level measures of physical function.

Activities of Daily Living↗
PubMed1998

Use of physical restraints in nursing homes in New South Wales, Australia.

A 48 item postal survey was completed voluntarily by 285/445 (64%) Directors of Nursing (hereafter DONs) of nursing homes in New South Wales, Australia, to obtain information about the use of physical restraints. Of a total of approximately 16,397 (11,719 females; 4678 males) residents of nursing homes from which information was obtained, 15.3% (2516) were physically restrained. Females comprised 11.2% (1839) and males 4.1% (677) of this group. The commonest forms of physical restraint were vests (25.3%), restraining belts (18.9%), bedrails (17.2%), lap trays (14.4%) and gerichairs (10.5%). The commonest patient-oriented reason for using physical restraints was to 'prevent falls' (84.2%) and the commonest nurse-oriented reasons were 'because no alternative exists' (39.6%) and 'to reduce legal liability' (20%). The correlation between the size of nursing homes (bed numbers) and the number of residents who were physically restrained was weak (r = 0.1771, alpha = 0.05), suggesting that nursing home size did not predict the use of physical restraints. Correlations between the total number of staff, the total number of untrained staff (Assistants In Nursing) and the number of residents who were physically restrained were also weak (r = 0.1792; 0.0921 respectively; alpha = 0.05), suggesting that these factors also had little predictive influence on the use of physical restraints. The findings of this research indicate that the extent to which physical restraints are currently being used in nursing homes in New South Wales should be of concern.

Accidental Falls↗
PubMed2003

Effects of physical activity on emotional well-being among older Australian women: cross-sectional and longitudinal analyses.

OBJECTIVE: To explore relationships between physical activity and mental health cross-sectionally and longitudinally in a large cohort of older Australian women. METHOD: Women in their 70s participating in the Australian Longitudinal Study on Women's Health responded in 1996 (aged 70-75) and in 1999 (aged 73-78). Cross-sectional data were analyzed for 10,063 women and longitudinal data for 6472. Self-reports were used to categorize women into four categories of physical activity at each time point as well as to define four physical activity transition categories across the 3-year period. Outcome variables for the cross-sectional analyses were the mental health component score (MCS) and mental health subscales of the Medical Outcomes Study Short Form (SF-36). The longitudinal analyses focused on changes in these variables. Confounders included the physical health component scale (PCS) of the SF-36, marital status, body mass index (BMI) and life events. Adjustment for baseline scores was included for the longitudinal analyses. RESULTS: Cross-sectionally, higher levels of physical activity were associated with higher scores on all dependent variables, both with and without adjustment for confounders. Longitudinally, the effects were weaker, but women who had made a transition from some physical activity to none generally showed more negative changes in emotional well-being than those who had always been sedentary, while those who maintained or adopted physical activity had better outcomes. CONCLUSION: Physical activity is associated with emotional well-being among a population cohort of older women both cross-sectionally and longitudinally, supporting the need for the promotion of appropriate physical activity in this age group.

Aged↗
PubMed1997

Color Doppler ultrasound criteria to diagnose varicoceles: correlation of a new scoring system with physical examination.

OBJECTIVES: Color Doppler ultrasound (CDU) diagnostic criteria for varicoceles are poorly defined, and the role of CDU in diagnosing varicoceles is controversial. The purpose of this study is to assess the diagnostic accuracy of CDU for varicoceles compared to physical examination. METHODS: We prospectively studied 64 patients with CDU and collected the following data: maximum diameter of scrotal veins, the presence of a venous plexus, sum of the diameter of up to six veins of the plexus, and the duration and amplitude of flow change on Valsalva maneuver. To avoid interphysician variation, all patients were examined by one designated senior urologist with the sonographer remaining unaware of the findings. RESULTS: CDU parameters of 127 testis units in 64 patients were analyzed and compared to the physical findings. Fifty-nine testis units were positive and 57 units were negative for varicocele on physical examination. In 11 testis units, results of physical examination were inconclusive regarding the presence of varicocele. The commonly accepted CDU criterion for varicocele (maximal vein diameter of 3 mm or greater) had a sensitivity of 53% and specificity of 91% compared to physical examination. We developed a new scoring system incorporating the maximal venous diameter (score 0 to 3), the presence of a venous plexus and the sum of the diameters of veins in the plexus (score 0 to 3), and the change of flow on Valsalva maneuver (score 0 to 3). Using a total score of 4 or more to define the presence of CDU-positive varicocele, we observed a sensitivity of 93% and a specificity of 85% when compared to physical examination. All moderate to large varicoceles found on physical examination were positive by CDU diagnosis using the scoring system, but the same group had only a 68% positive rate by traditional CDU diagnostic criteria. CONCLUSIONS: Using the proposed new scoring system, CDU has been shown to be a reliable and accurate method of diagnosis for varicoceles compared to the current reference standard physical examination. CDU has the advantages of being able to objectively examine venous plexus and measure blood flow parameters and to be less observer-dependent than physical examination.

Adult↗
PubMed1987

Reduction of premature mortality by high physical activity: a 20-year follow-up of middle-aged Finnish men.

The association of physical activity level with the risk of death was analysed for a cohort of 636 healthy Finnish men aged 45-64 years followed up for 20 years. 39% of the cohort were classed as highly active physically at baseline in 1964. Up to 1984 there were 287 deaths, 106 of them due to coronary heart disease (CHD). During the first-two thirds of the follow-up, men with high physical activity had a lower risk of death than did men with low physical activity. During the last third, the survival curves of the men with high and low physical activity gradually converged. Of the men who died, those with high physical activity lived 2.1 years longer (p = 0.002) than those with low physical activity, after adjustment for age, smoking, blood pressure, serum cholesterol, and body mass index. This difference was due mainly to fewer CHD deaths among the highly active group. Low physical activity was clearly weaker than smoking as a predictor of risk of death. High physical activity may thus independently prevent premature death among middle-aged men, but it probably does not prolong the maximum achievable life-span.

Adult↗
PubMed2000

Physical functioning and health-related quality-of-life changes with exercise training in hemodialysis patients.

The Renal Exercise Demonstration Project was designed to test the effects of two different approaches to exercise programming on the levels of physical activity, physical functioning, and self-reported health status in hemodialysis patients. Two hundred eighty-six patients were recruited for participation. Intervention patients were given individually prescribed exercise for 8 weeks of independent home exercise, followed by 8 weeks of incenter cycling during dialysis. Physical performance testing was performed at baseline and after each intervention using gait speed, sit-to-stand test, and 6-minute walk. The Medical Outcomes Study Short Form 36-item (SF-36) questionnaire was used to assess self-reported health status. The intervention group showed increased participation in physical activity. There were significant differences between the intervention and nonintervention groups in change over time in normal and fast gait speed, sit-to-stand test scores, and the physical scales on the SF-36, including the physical component scale. The intervention group improved in these test results, whereas the nonintervention group either did not change or declined over the duration of the study. It is clear that improvements in physical functioning result from exercise counseling and encouragement in hemodialysis patients. Because self-reported physical functioning is highly predictive of outcomes in hemodialysis patients, more attention to patients' levels of physical activity is warranted.

Activities of Daily Living↗
PubMedDate not supplied

Effects of physical activity and exercise on experimentally-induced mammary carcinogenesis.

Physical activity is defined as skeletal muscle contraction resulting in a quantifiable expenditure of energy, whereas exercise is a specific type of physical activity in which planned, structured, and repetitive bodily movement is done to improve or maintain one or more components of physical fitness. The focus of laboratory studies of the physical activity-breast cancer hypothesis has been on evaluating how various types of physical activity including exercise affect the process of mammary carcinogenesis. A key objective has been the evaluation of the characteristics of physical activity, i.e. intensity, duration, and frequency, required to confer protection against experimentally-induced breast cancer. The results of those studies indicate that exercise rather than physical activity can exert a greater inhibitory effect against experimentally-induced breast cancer, and that the duration of exercise may not be as important as its intensity. This finding differs from evidence that other health benefits attributed to physical activity are proportional to the total amount of activity rather than the manner in which it is obtained. In this review criteria are defined for categorizing laboratory studies into those that investigated the effects of physical activity versus exercise on experimentally-induced mammary carcinogenesis, and the literature is reinterpreted in this context.

Animals↗
PubMed1997

Exercise and self-esteem in middle-aged adults: multidimensional relationships and physical fitness and self-efficacy influences.

In the context of sedentary middle-aged adults, the present study examined the relationships among domain-specific and global levels of self-esteem over the course of a 20-week exercise program. Additionally, the roles played by physical fitness, body composition, self-efficacy, and exercise participation as possible contributors to changes in physical self-worth were examined. Significant improvements in self-esteem at all levels were discovered with global esteem, physical self-worth, and perceptions of physical condition and attractive body increasing. Tests of the hierarchical structure of self-esteem showed greater improvements in physical condition and physical self-worth than global esteem and the relationships between global esteem and subdomain levels were shown to be mediated by physical self-worth. Hierarchical regression analyses showed changes in ratings of importance to have little impact on changes in physical self-worth. Both changes in efficacy and aerobic capacity were demonstrated to account for modest but significant variation in physical self-esteem. Results are discussed in terms of contemporary models of self-esteem, potential mediators of exercise effects on esteem, and the need to measure the constructs of interest appropriately.

Body Image↗
PubMed1992

Return to work after spinal cord injury: the potential contribution of physical fitness.

The history, physical characteristics and fitness status of 60 persons who had sustained a spinal cord injury at least 3 years previously were considered in relation to current occupation. All subjects had completed their education, 39 being gainfully employed and 21 unemployed. The general characteristics of the sample, mainly beneficiaries of the Quebec Automobile Insurance Plan, were typical of spinal cord injured individuals in North America. The working group had a significantly higher current level of education than those who were unemployed (p less than .01). In terms of physical fitness, the workers were lighter, with a lower body mass index and a higher aerobic power (p less than .05). Isokinetic testing suggested a trend toward a higher peak torque in the workers. The total work performed (Nm.kg-1) during an isokinetic endurance test (25 biphasic contraction at 180 degrees.sec-1) was significantly higher in the workers, suggesting that such muscular endurance might be even more useful than greater peak isokinetic strength during vocational activities. However, the likelihood of employment was unrelated to habitual patterns of either aerobic exercise or overall physical activity. No significant differences of physical fitness or physical activity habits were found between workers holding sedentary versus physically demanding jobs. The results verified the positive relationship between physical fitness (body composition, aerobic power, muscular endurance) and the gainful employment of paraplegics, but failed to show any significant relationship between physical fitness and the acceptance of physically demanding work by such individuals.

Adolescent↗
PubMed1999

How physically active are American children and what can we do about it?

Any discussion of obesity in youth must consider physical activity level or energy output. Many suggest that increasing levels of obesity among children is the direct result of declining levels of physical activity. There is accumulating evidence that physical activity among youth has declined over the past several decades. Less time is spent on physical education classes in school and many popular activities among youth such as television and computer games, involve minimal physical exertion. These observations are confirmed by studies of physical fitness and endurance. These measures have also declined among youth. Much has been learned about the factors associated with physical activity among youth. These factors were used to develop several innovative school-based programs which demonstrate increased physical activity and performance. Recommendations are made for increasing physical activity both in the school curriculum and outside the school day. Potential health benefits and likely effects on obesity are substantial.

Adolescent↗
PubMed1998

Elevated heart rate variability in physically active young and older adult women.

1. Low heart rate variability is associated with an increased risk of cardiac sudden death, coronary heart disease and all-cause mortality. We have previously shown that physically active postmenopausal women demonstrate higher levels of heart rate variability and cardiac baroreflex sensitivity compared to their sedentary peers. The purpose of the present prospective study was to test the hypothesis that heart rate variability and cardiac baroreflex sensitivity would be reduced with age in sedentary but not physically active women. To accomplish this, we measured heart rate variability (both time and frequency domain) and spontaneous cardiac baroreflex sensitivity (SBRS, sequence method) in the sitting posture in 23 sedentary women [11 premenopausal and 12 postmenopausal (age, 28 +/- 1 and 61 +/- 2 years; VO2max, 35.3 +/- 1.4 and 21.7 +/- 1.5 ml.min-1.kg-1 respectively] and in 22 physically active women [12 premenopausal and 10 postmenopausal (age, 31 +/- 1 and 59 +/- 2 years; VO2max, 52.5 +/- 1.4 and 39.7 +/- 1.8 ml.min-1.kg-1)]. 2. The S.D. of the R-R interval (time domain) was reduced (P < 0.05) with age in both sedentary (52 +/- 6 versus 33 +/- 4 ms) and physically active women (72 +/- 8 versus 49 +/- 9 ms). The high-frequency power (3740 +/- 1527 versus 915 +/- 188 and 9516 +/- 2849 versus 2803 +/- 1083 ms2/Hz), total power of heart rate variability and SBRS (11 +/- 2 versus 7 +/- 2 and 19 +/- 3 versus 13 +/- 2 ms/mmHg) also demonstrated similar age-related reductions in sedentary and physically active women, respectively (all P < 0.05). The S.D. of the R-R interval, high-frequency and total power of heart rate variability, and SBRS were higher (all P < 0.05) in the physically active compared with the sedentary women at any age. There was no significant influence of age or physical activity status on the low-frequency power of heart rate variability. In addition, no significant differences in any of the time or frequency domain measures of heart rate variability or SBRS were observed in users compared with non-users of hormone replacement therapy. 3. The results of the present study suggest that heart rate variability and cardiac baroreflex sensitivity decline similarly with age in healthy sedentary and physically active women. However, physically active women demonstrate higher levels of heart rate variability and cardiac baroreflex sensitivity compared with their sedentary peers, regardless of age.

Adult↗
PubMedDate not supplied

Establishing an effective framework for physical activity counseling in primary care settings.

This article examines the role of the primary care physician in providing physical activity counseling and proposes a framework for maximizing the effectiveness of this activity. Many studies have been conducted to evaluate the effectiveness of physical activity counseling in the primary care setting. Unfortunately, the results of most of these studies have not been encouraging as there has not been compelling evidence that brief physical activity counseling for the general population results in long-term changes in physical activity behaviors. In contrast, the evidence of health improvements in patients who are successful in achieving levels of physical activity consistent with the Surgeon General's recommendations is compelling and should serve as the source of motivation as we seek more effective paradigms for physical activity counseling. The PACE (Patient-Centered Assessment and Counseling for Exercise and Nutrition) Program is presented as an evidenced-based and effective framework for effective physical activity counseling. By adopting a patient-centered approach to counseling and by tailoring the message to the readiness of the patient to take action, it is possible to engage in physical activity counseling in a cost- and time-effective manner. This article provides specific counseling strategies for addressing patients at various stages of readiness to engage in behavior change regarding physical activity.

Counseling↗
PubMed1999

Association of physical fitness with LDL and HDL subfractions in young healthy men.

A dyslipoproteinemia of increased concentrations of small, dense LDL particles and reduced HDL2 cholesterol has shown to be associated with coronary heart disease (CHD). In contrast, an increase in physical fitness and a reduction of body mass index (BMI) improve the lipoprotein profile and reduce the incidence of cardiovascular events. The association of physical exercise, physical fitness, and body weight with an atherogenic lipoprotein subfraction profile has been investigated before in obese subjects, but the relationship is unknown in a healthy non-obese population without insulin resistance or CHD. Therefore, a detailed lipoprotein subfraction profile of 3 HDL and 6 LDL subfractions was determined in 125 healthy men (26+/-5 years). Physical fitness (maximal oxygen consumption, VO2max) was assessed by ergometry and physical activity by questionnaire. Those men with the lowest physical fitness (VO2max < 40 ml/kg/min) and the lowest physical activity score had a significantly less favourable lipoprotein subfraction profile of increased concentration of small, dense LDL particles (d: > 1.044 g/ml) and reduced HDL2a cholesterol than those with a VO2max >50 ml/kg/min. Multivariate regression analysis revealed that concentrations of small, dense LDL particles were primarily determined by BMI whereas HDL2a cholesterol and apolipoprotein A-I were primarily determined by physical fitness. These findings underline the relationship between a good physical fitness, a low body weight, and a favourable lipoprotein subfraction profile even in a healthy young male population.

Adult↗
PubMed1993

Triggering of acute myocardial infarction by heavy physical exertion. Protection against triggering by regular exertion. Determinants of Myocardial Infarction Onset Study Investigators.

BACKGROUND: Despite anecdotal evidence suggesting that heavy physical exertion can trigger the onset of acute myocardial infarction, there have been no controlled studies of the risk of myocardial infarction during and after heavy exertion, the length of time between heavy exertion and the onset of symptoms (induction time), and whether the risk can be modified by regular physical exertion. To address these questions, we collected data from patients with confirmed myocardial infarction on their activities one hour before the onset of myocardial infarction and during control periods. METHODS: Interviews with 1228 patients conducted an average of four days after myocardial infarction provided data on their usual annual frequency of physical activity and the time, type, and intensity of physical exertion in the 26 hours before the onset of myocardial infarction. We compared the observed frequency of heavy exertion (6 or more metabolic equivalents) with the expected values using two types of self-matched analyses based on a new case-crossover study design. The low frequency of heavy exertion during the control periods was validated by data from a population-based control group of 218 subjects. RESULTS: Of the patients, 4.4 percent reported heavy exertion within one hour before the onset of myocardial infarction. The estimated relative risk of myocardial infarction in the hour after heavy physical exertion, as compared with less strenuous physical exertion or none, was 5.9 (95 percent confidence interval, 4.6 to 7.7), Among people who usually exercised less than one, one to two, three to four, or five or more times per week, the respective relative risks were 107 (95 percent confidence interval, 67 to 171), 19.4 (9.9 to 38.1), 8.6 (3.6 to 20.5), and 2.4 (1.5 to 3.7). Thus, increasing levels of habitual physical activity were associated with progressively lower relative risks. The induction time from heavy exertion to the onset of myocardial infarction was less than one hour, and symptoms usually began during the activity. CONCLUSIONS: Heavy physical exertion can trigger the onset of acute myocardial infarction, particularly in people who are habitually sedentary. Improved understanding of the mechanisms by which heavy physical exertion triggers the onset of myocardial infarction and the manner in which regular exertion protects against it would facilitate the design of new preventive approaches.

Adult↗
PubMed2003

Validity and repeatability of a simple index derived from the short physical activity questionnaire used in the European Prospective Investigation into Cancer and Nutrition (EPIC) study.

OBJECTIVE: To assess the validity and repeatability of a simple index designed to rank participants according to their energy expenditure estimated by self-report, by comparison with objectively measured energy expenditure assessed by heart-rate monitoring with individual calibration. DESIGN: Energy expenditure was assessed over one year by four separate episodes of 4-day heart-rate monitoring, a method previously validated against whole-body calorimetry and doubly labelled water. Cardio-respiratory fitness was assessed by four repeated measures of sub-maximum oxygen uptake. At the end of the 12-month period, participants completed a physical activity questionnaire that assessed past-year activity. A simple four-level physical activity index was derived by combining occupational physical activity together with time participating in cycling and other physical exercise (such as keep fit, aerobics, swimming and jogging). SUBJECTS: One hundred and seventy-three randomly selected men and women aged 40 to 65 years. RESULTS: The repeatability of the physical activity index was high (weighted kappa=0.6, ). There were positive associations between the physical activity index from the questionnaire and the objective measures of the ratio of daytime energy expenditure to resting metabolic rate and cardio-respiratory fitness As an indirect test of validity, there was a positive association between the physical activity index and the ratio of energy intake, assessed by 7-day food diaries, to predicted basal metabolic rate. CONCLUSIONS: The summary index of physical activity derived from the questions used in the European Prospective Investigation into Cancer and Nutrition (EPIC) study suggest it is useful for ranking participants in terms of their physical activity in large epidemiological studies. The index is simple and easy to comprehend, which may make it suitable for situations that require a concise, global index of activity.

Adult↗
PubMed1991

Physical education's role in public health.

The public health community is becoming increasingly interested in the potential contributions of school physical education to child health. School physical education is seen as an ideal site for the promotion of regular physical activity because up to 97% of elementary school children participate in some sort of physical education program. For maximal public health benefit, school physical education programs should prepare children for a lifetime of physical activity. This public health goal for physical education may require some changes in current approaches. Physical educators are challenged to collaborate with public health professionals in developing and evaluating school physical education programs that will improve the health of the nation's youth.

Cardiovascular Diseases↗