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At least 19 recordsLinked to original sources
PubMed1998

Prediction of physical fitness and physical activity level in adulthood by physical performance and physical activity in adolescence--an 18-year follow-up study.

The aim of the study was to investigate relationships between physical fitness and self-reported physical activity in adulthood and to what extent the level of physical fitness and leisure-time physical activity in adulthood can be explained by anthropometric measures, physical performance, physical activity, attitudes to sports activities and socio-demographic characteristics at the age of 16. A group of 157 men and 121 women was tested at the ages of 16 and 34 by means of questionnaires and fitness tests. Physically active men and women had higher estimated VO2 max and performed better in curl ups and bench press than those who were inactive. Performance in physical tests, height, weight and physical activity at the age of 16 contributed best to explain adult physical performance and physical activity. The magnitude of explanation varied between 10% (9-min run test) and 56% (bench press test); it was in general lower in the men than in the women. The various fitness tests and physical activity were explained by different predictors and the predictors also differed between men and women. The findings about attitudes to sports and socio-demographic factors at a young age that influence adult physical activity habits and fitness are very complex and further research is required to identify specific inactivity risks.

Adolescent↗
PubMed1994

Prediction of physical activity level in adulthood by physical characteristics, physical performance and physical activity in adolescence: an 11-year follow-up study.

The purpose of the study was to investigate to what extent the physical activity pattern in adulthood can be predicted by physical characteristics, performance and activity in adolescence. A group of 62 men and 43 women completed a questionnaire concerning physical activity during their leisure time at the ages of 16 and 27 years. An activity index produced from the questionnaire. At the age of 16 years, the subjects were also tested for strength (strength test battery) and running performance (9-min run). Maximal oxygen uptake (VO2max) was estimated from a submaximal test and a muscle biopsy specimen was taken and analysed for fibre types (percentages of types I, IIA, IIB). The proportion of subjects engaged in some kind of physical activity during their leisure time was approximately 70% among the women and 80% among the men at both ages. The time spent on physical activity (minutes per week) decreased with age for the men but not for the women. The women devoted less time to physical activity than the men both at age 16 and 27 years. The attitude to endurance activities had changed to a more positive attitude among the women and to a less positive attitude among the men at age 27 years. The aerobic potential (VO2max and percentage of type I fibre), running performance, strength performance, physical activity and marks in physical education at age 16 years explained 82% of the physical activity level in adulthood for the women and 47% for the men.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2003

The effectiveness of worksite physical activity programs on physical activity, physical fitness, and health.

OBJECTIVE: To critically review the literature with respect to the effectiveness of worksite physical activity programs on physical activity, physical fitness, and health. DATA SOURCES: A search for relevant English-written papers published between 1980 and 2000 was conducted using MEDLINE, EMBASE, Sportdiscus, CINAHL, and Psychlit. The key words used involved a combination of concepts regarding type of study, study population, intervention, and outcome measure. In addition, a search was performed in our personal databases, as well as a reference search of the studies retrieved. STUDY SELECTION: The following criteria for inclusion were used: 1) randomized, controlled trial or nonrandomized, controlled trial; 2) working population; 3) worksite intervention program to promote employees' physical activity or physical fitness; and 4) physical activity, physical fitness, or health-related outcomes. DATA EXTRACTION: Two reviewers independently evaluated the quality of relevant studies using a predefined set of nine methodological criteria. Conclusions regarding the effectiveness of a worksite physical activity programs were based on a rating system consisting of five levels of evidence. DATA SYNTHESIS: Fifteen randomized, controlled trials and 11 nonrandomized, controlled trials met the criteria for inclusion and were reviewed. Six randomized, controlled trials and none of the nonrandomized, controlled trials were of high methodological quality. Strong evidence was found for a positive effect of a worksite physical activity program on physical activity and musculoskeletal disorders. Limited evidence was found for a positive effect on fatigue. For physical fitness, general health, blood serum lipids, and blood pressure, inconclusive or no evidence was found for a positive effect. CONCLUSIONS: To increase the level of physical activity and to reduce the risk of musculoskeletal disorders, we support implementation of worksite physical activity programs. For the other outcome measures, scientific evidence of the effectiveness of such a program is still limited or inconclusive, which is mainly the result of the small number of high-quality trials. Therefore, we recommend performing more randomized, controlled trials of high methodological quality, taking into account criteria such as randomization, blinding, and compliance.

Health Promotion↗
PubMed1981

[Studies on differences in the preventive effects of habitual physical activity in occupation versus leisure time. II. Effects of physical activity in occupation versus leisure time on physical working capacity (author's transl)].

One hundred and twenty men, aged 23--60 years and having various professions participated in studies on relationships between daily physical activity and physical performance capacity (PPC). The determination of daily physical activity at work and of the habitual leisure time activities has been described earlier (Ilmarinen et al. 1980). The determination of physical performance capacity was based on W170, W85% and on predicted VO2 max measured with continuously increasing work load on a bicycle ergometer. The W85% modification corresponds to the working capacity at a heart rate level of 85% of maximal heart rate. Workers with a combination of heavy physical work and active leisure time showed systematically the highest absolute and relative values of PPC. However, although the results indicated that the effect of work activity on PPC was not significant, the effects of leisure time activities on W85% and on VO2 max related to lean body mass were significant. It is concluded that the leisure time sport activities are more important than the physical activity at work in maintaining or increasing the PPC. Aerobic sport activities in leisure time are recommended both for persons with physically heavy and light work.

Adult↗
PubMed1987

Protection against ischemic heart disease in the Belgian Physical Fitness Study: physical fitness rather than physical activity?

Occupational and leisure time physical activity and conventional risk factors were determined in the Belgian Physical Fitness Study, a prospective study of 2,363 healthy male factory workers who were aged 40-55 years at entry in 1976-1978 and who were followed for five years. Physical fitness, defined as the interpolated physical working capacity at heart rate 150 beats per minute, was measured in 2,109 subjects. In this subgroup, there were 31 myocardial infarctions and sudden deaths. Smoking, physical fitness, and high density lipoprotein cholesterol (HDL cholesterol) were independent risk indicators for subsequent ischemic heart disease, while both physical activity scores were not. It is concluded that in this healthy, predominantly sedentary population, the fitness level, but not the physical activity pattern, is an independent protective factor against ischemic heart disease.

Adult↗
PubMed2002

Tissue adaptation to physical stress: a proposed "Physical Stress Theory" to guide physical therapist practice, education, and research.

The purpose of this perspective is to present a general theory--the Physical Stress Theory (PST). The basic premise of the PST is that changes in the relative level of physical stress cause a predictable adaptive response in all biological tissue. Specific thresholds define the upper and lower stress levels for each characteristic tissue response. Qualitatively, the 5 tissue responses to physical stress are decreased stress tolerance (eg, atrophy), maintenance, increased stress tolerance (eg, hypertrophy), injury, and death. Fundamental principles of tissue adaptation to physical stress are described that, in the authors' opinion, can be used to help guide physical therapy practice, education, and research. The description of fundamental principles is followed by a review of selected literature describing adaptation to physical stress for each of the 4 main organ systems described in the Guide to Physical Therapist Practice (ie, cardiovascular/pulmonary, integumentary, musculoskeletal, neuromuscular). Limitations and implications of the PST for practice, research, and education are presented.

Adaptation, Physiological↗
PubMed2000

Methodologic issues in measuring physical activity and physical fitness when evaluating the role of dietary supplements for physically active people.

Physical activity and physical fitness are complex entities comprising numerous diverse components that present a challenge in terms of accurate, reliable measurement. Physical activity can be classified by its mechanical (static or dynamic) or metabolic (aerobic or anaerobic) characteristics and its intensity (absolute or relative to the person's capacity). Habitual physical activity can be assessed by using a variety of questionnaires, diaries, or logs and by monitoring body movement or physiologic responses. Selection of a measurement method depends on the purpose of the evaluation, the nature of the study population, and the resources available. The various components of physical fitness can be assessed accurately in the laboratory and, in many cases, in the field by using a composite of performance tests. Most coaches and high-level athletes would accept as very beneficial a dietary supplement that would increase performance in a competitive event by even 3%; for example, lowering a runner's time of 3 min, 43 s in the 1500 m by 6.7 s. To establish that such small changes are caused by the dietary supplement requires carefully conducted research that involves randomized, placebo-controlled, double-blind studies designed to maximize statistical power. Statistical power can be increased by enlarging sample size, selecting tests with high reliability, selecting a potent but safe supplement, and maximizing adherence. Failure to design studies with adequate statistical power will produce results that are unreliable and will increase the likelihood that a true effect will be missed.

Data Collection↗
PubMed1994

Skeletal muscle fibre types, physical performance, physical activity and attitude to physical activity in women and men. A follow-up from age 16 to 27.

Fifty-five men and 28 women were tested at age 16 and retested at age 27. Muscle biopsies were taken from m. vastus lateralis to analyse fibre types, fibre areas and enzyme contents. A cycle ergometer test to was used to estimate the maximal oxygen uptake. Physical performance was assessed in an endurance test, where the subjects had to run as far as possible in 9 min on a 400-m track, and in three strength tests designed to test maximal dynamic strength (Sargent jump) and maximal static strength (handgrip test, two-hand lift). The subjects answered a questionnaire concerning physical activity during their leisure time and an activity index was calculated from the answers. The relative proportion of type I fibres (type I%) tended to increase with age in women and decreased in men. At age 27, the type I% was higher in women than in men. Multiple regression analysis indicated that sex per se could explain some of the interindividual variation in the type I% at age 27 and in the changes with age in the type I%, but also factors as physical activity (increase in type I%) and smoking (decrease in type I%) probably contributed to the variation. VO2max (ml.kg-1.min-1) increased with age in women and was unchanged in men so that there was no significant sex difference in VO2max at age 27. Running performance remained unchanged from age 16 to age 27 in both sexes and men performed better than women at both ages. Running performance was directly related to the type I% for both women and men at age 27, a relationship which existed also for men at age 16, but not for women at that age. It seems that the age related changes in relationship between running performance and type I% may be related to the altered choice of physical activity from speed and strength to more endurance demanding activities and the increased VO2max in the women. This may allow an adaptation of the skeletal muscle towards type I fibres in the active ones. The sex differences in strength increased from age 16 to age 27. The relationship between strength and the type II% in the women changed with age from a positive correlation (Sargent jump only, partiell correlation after body dimensions were considered) to negative correlations for all the strength tests, i.e. the more type I fibres the stronger. A positive correlation between strength and activity index was revealed in the women at both ages.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1988

Physical disability: the role of the physical scientist in the health service. A report of the Institute of Physical Sciences in Medicine.

The Report of the Royal College of Physicians on Physical Disability in 1986 and Beyond gives details of a Medical Disability Service to redress the present imbalance in the provisions for the physically disabled. An integral part of this service should be the provision of adequate scientific and technical resources, which could be established by making four or five new Medical Physics and Clinical Engineering appointments annually in each Region for the next ten years.

Biomedical Engineering↗
PubMed1977

[Evaluation of tolerance of prolonged physical work as a function of the degree of endurance. I. Useflness of various tests determining physical endurance and the physiological cost of long-term physical exertion].

The physical capacity was determined in 23 men (aged from 19 to 27) using the following set of tests: Astrand and Ryhming's test, PWC170, PWC130, LPI, Crampton's test. The 70 min effort on the bicycle ergometer was considered as the model of prolonged work and the following parameters were accepted as standards of physiological cost of work; oxygen consumption, mechanical efficiency, heart rate during the work, stroke volume and cardiac output as well as the sum of systoles during recovery. The results of the correlation analysis point out that, at a given work intensity. the heart rate depends on results of PWC170 test and the systoles sum during recovery on the results of Crampton's tests. The capacity determined with used tests had no effect on the remaining indices of the cost of physical work.

Adult↗
PubMedDate not supplied

Adolescent motor skill and performance: is physical activity in adolescence related to adult physical fitness?

In the Amsterdam Growth and Health Longitudinal Study (AGAHLS), a cohort of about 400 boys and girls (mean age 13 years) were followed over a period of 20 years. Over that period repeated measurements were done of body dimensions (height, weight, skinfolds), physical fitness (eight motor performance field tests: plate tapping, bent arm hang, 10 x 5 m sprint, arm pull, sit and reach, standing high jump, 10 leg lifts, 12-min endurance run, and one laboratory test to measure maximal aerobic power), and physical activity (by a cross-check interview). Three research questions were studied: (1) Is there a positive relationship between adolescent fitness (age 13-17 years) and adult physical activity (age 33 years)? (2) Do physical fitness and physical activity track from adolescence into adulthood? (3) What is the longitudinal relationship between physical fitness and physical activity? Multiple linear regression analysis showed that of the 9 physical fitness tests, only the 12-min endurance run and the maximal aerobic power during adolescence are significant (P < 0.05) predictors of adult physical activity. The effects are not influenced by biological age but by sex: only in females are the predictions significant (P < 0.05) Tracking over the period of 20 years estimated from stability coefficients showed values for physical fitness varying between 0.83 (plate tapping) to 0.38 (standing high jump and maximal aerobic power). Physical activity shows lower stability coefficients (0.35-0.29). A longitudinal linear regression technique was used to analyse the relationship between physical activity and physical fitness over the 20-year period; in this analysis corrections were made for both time-dependent (time, biological age, and cardiovascular factors) and time-independent variables (sex). All physical fitness tests show positive and significant (P < 0.05) standardized regression coefficients with physical activity, but the explained variance is less than 1%. Only maximal aerobic power has a higher explained variance of 1.8%. It can be concluded that: (1) Physical fitness in adolescence is only weakly related to adult physical activity; (2) between age 13 and 33 years, physical activity has low stability and physical fitness was higher stability; and (3) the longitudinal relationships between physical fitness and physical activity are only meaningful with maximal aerobic power.

Adolescent↗
PubMed1993

The importance of physical fitness versus physical activity for coronary artery disease risk factors: a cross-sectional analysis.

Numerous epidemiological investigations have shown that low physical fitness and low physical activity are related to the incidence of coronary artery disease (CAD). Most studies, however, have not examined both variables concurrently to determine which has the strongest association with CAD risk. The purpose of this investigation was to cross-sectionally examine the relationships among physical fitness, physical activity, and risk factors for CAD. Male law enforcement officers (N = 412) from the City of Austin, Texas, were subjects for this study. Physical fitness, physical activity, and risk factors for CAD were assessed through health screenings and from data collected as part of an annual physical fitness assessment. Multivariate analysis of covariance revealed that physical fitness, but not physical activity, was related to several single CAD risk factors. Percent body fat, smoking habits, and Type A behavior score were negatively related to physical fitness level, and high density lipoprotein (HDL) cholesterol was positively related to physical fitness level. Univariate analysis of variance found both physical fitness and physical activity to be significantly related to a composite CAD risk score. Low physical fitness and low physical activity were associated with a high CAD risk score. These data suggest that physical activity must be sufficient to influence physical fitness before statistically significant risk-reducing benefits on single CAD risk factors are obtained, although minimal engagement in weekly vigorous activity provides a significant benefit for the composite CAD risk score. It is plausible, however, that physical fitness is a stronger measure than physical activity and optimally characterizes the relationship among physical activity and CAD risk factors.

Adult↗
PubMed2001

Childhood physical abuse, early social support, and risk for maltreatment: current social support as a mediator of risk for child physical abuse.

OBJECTIVE: The study investigated whether perceptions of social support in adulthood partially mediated the associations between childhood experiences (i.e., receipt of physical abuse and levels of early social support) and adult risk for child physical abuse. METHOD: Participants included 598 general population adults who completed self-report measures designed to assess childhood physical abuse, perceptions of early and current social support, and risk factors for child physical abuse. Structural equation modeling was used to test and cross validate a model that included the direct effects of child physical abuse and early social support on child physical abuse risk, as well as mediated effects through an influence on adult perceptions of social support. RESULTS: Childhood physical abuse and early social support covaried, such that receipt of physical abuse was associated with lower levels of perceived early social support. Early support, but not child physical abuse, had an indirect effect (i.e., through current support) on child physical abuse risk. More specifically, levels of early support were directly related to adult perceptions of support, and adult perceptions of support were inversely associated with child physical abuse risk. Childhood physical abuse was directly related to child physical abuse risk. CONCLUSIONS: Low levels of early support may impact risk for child physical abuse by affecting perceptions of others as supportive in adulthood. The receipt of physical abuse in childhood, however, does not appear to impact perceptions of support in adulthood. Research is needed to identify additional factors that may explain the association between receipt of physical abuse in childhood and increased risk of child physical abuse in adulthood.

Adolescent↗
PubMedDate not supplied

Relationship of physical symptoms and physical functioning to depression in patients with heart failure.

OBJECTIVE: The purpose of this study was to determine the relative contribution of physical symptoms and physical functioning to depression in adult patients with heart failure during hospitalization and the early postdischarge period. DESIGN: An exploratory, correlational longitudinal design was used. PATIENTS: The sample included 170 subjects with heart failure. RESULTS: Subjects' mean scores on the depression scale indicated that subjects were not depressed on average; however, 30% of the sample (n = 52) had scores indicative of clinical depression. Both physical symptoms (r = 0.48) and physical functioning (r = -0.32) were moderately correlated with depression. Physical symptoms contributed 13% uniquely to the variance in depression while physical functioning contributed only 2% uniquely to the variance in depression. Multiple regression analyses indicated that physical symptomatology is more closely related to depression than is physical functioning in adults with heart failure. CONCLUSIONS: This study showed the patients with heart failure who had increased physical symptoms and poorer physical functioning reported increased symptoms of depression. Physical symptoms explained a greater portion of the variance in depression than did physical functioning. Thus, it appears that patients with heart failure are affected emotionally by both their physical symptoms and their limitations in their physical functioning, but depression is more strongly related to having more physical symptoms than having greater limitations in physical functioning.

Adult↗
PubMed2000

Children's physical activity and physical self-perceptions.

The aim of this study was to determine the relationship between physical self-perceptions and physical activity in Canadian school children aged 10-14 years. The sample consisted of 220 boys and 246 girls in grades 5-8. Physical activity was assessed by 7-day recall using the Physical Activity Questionnaire for Older Children. Self-perceptions of physical conditioning, sports competence, strength, body appearance and general physical self-worth were measured by the Physical Self-Perception Profile (PSPP). We found that boys were more physically active than girls and had higher perceptions of sport competence and strength. All PSPP scales were significantly correlated with physical activity in both boys and girls. Structural equation modelling procedures found the hierarchical PSPP model provided a good fit to the observed data, with little evidence of differences between the sexes. Analysis of five alternative structural models of the relationship between the PSPP and physical activity found the most parsimonious model to have significant pathways from both physical conditioning and sport skills to physical activity. Models for the sample as a whole, for boys and for girls were similar, accounting for an R2 of 0.27-0.29 for physical activity. Our results demonstrate that physical self-perceptions, especially physical conditioning and sport skills, are significant correlates of activity in this population.

Child↗