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PubMed2006

Structure and biomechanics of peripheral nerves: nerve responses to physical stresses and implications for physical therapist practice.

The structural organization of peripheral nerves enables them to function while tolerating and adapting to stresses placed upon them by postures and movements of the trunk, head, and limbs. They are exposed to combinations of tensile, shear, and compressive stresses that result in nerve excursion, strain, and transverse contraction. The purpose of this appraisal is to review the structural and biomechanical modifications seen in peripheral nerves exposed to various levels of physical stress. We have followed the primary tenet of the Physical Stress Theory presented by Mueller and Maluf (2002), specifically, that the level of physical stress placed upon biological tissue determines the adaptive response of the tissue. A thorough understanding of the biomechanical properties of normal and injured nerves and the stresses placed upon them in daily activities will help guide physical therapists in making diagnoses and decisions regarding interventions.

Animals↗

PubMed2005

Physical performance and physical activity in grown-up congenital heart disease.

AIM: To review exercise performance and exercise habits in patients with congenital heart disease (CHD). BACKGROUND AND METHODS: Physical exercise and physical activity has shown beneficial effects on the physical, psychological and social level in adult patients with cardiovascular disease. Favourable effects have also been documented in children with CHD. Exercise testing is preferentially performed on a treadmill in children, with the measurement of gas exchange. RESULTS: An overview of the literature showed that formal exercise testing has frequently documented reduced or suboptimal values for aerobic exercise performance in children with left-to-right shunts (atrial septal defect, ventricular septal defect), valvular heart disease and obstructive anomalies (aortic stenosis, pulmonary stenosis, coarctation of the aorta). Subnormal values for exercise tolerance have also been observed in patients with successfully repaired cyanotic heart disease (tetraology of Fallot, transposition of the great arteries, Fontan operation). An important contributing factor to the impaired exercise performance is the hypoactive lifestyle, as often observed in patients with CHD. This frequently results from parental or environmental overprotection. CONCLUSION: These patients should be stimulated to be physically active, unless medical restriction is imposed. Fortunately, this represents only a small fraction of the total number of congenital heart defects for which sports participation is allowed.

Adult↗

PubMed2004

Ready to be physically active? The effects of a course preparing low-income multiethnic women to be more physically active.

The purpose of this study is to evaluate the effect of a preintervention physical activity preparatory course on physical activity, and social, cognitive, and transtheoretical constructs. The sample included 82 low-income, multiethnic women (75% Latina) who completed an 8-week course designed to prepare them to become more active prior to randomization into a 10-month physical activity intervention. Participants completed precourse and postcourse measures. Paired-comparison t tests showed increases in knowledge, perceived social support for exercise, minutes of walking per week, and total cognitive and behavioral processes following the preparatory course. Perceived barriers and self-efficacy for exercise did not change from precourse to postcourse. Preintervention preparatory courses may be an effective way to increase social and cognitive constructs associated with physical activity behavior, potentially yielding a greater effect from subsequent interventions.

Adolescent↗

PubMedDate not supplied

Predictors of physical activity stage of change among adults with physical disabilities.

PURPOSE: To use the Transtheoretical Model (TTM) constructs to examine the most important physical activity stage of change predictors for mostly inactive adults with physical disabilities. METHODS: A cross-sectional survey completed on the Internet. One hundred fifty-one individuals with physical disabilities (50% response rate) completed the survey questionnaires. Self-report standardized measures were used. RESULTS: A direct discriminant function analysis revealed that the most important stage of change predictors were the behavioral (r2 = .88) and cognitive (r2 = .50) processes of change, followed by self-efficacy (r2 = .33) and decisional balance (r2 = .13). The most accurate stages in prediction were the contemplation (76.3%), preparation (58.3%), and precontemplation (40%) stages, whereas the least accurate stages were the action (0.0%) and maintenance (8.3%) stages. CONCLUSION: Health promoters and educators may use strategies from the TTM to develop theory-driven physical activity motivational programs for the posited populace. Considering the cross-sectional design, study replication is warranted.

Adult↗

PubMed2000

Physical characterization of the homoeologous group 5 chromosomes of wheat in terms of rice linkage blocks, and physical mapping of some important genes.

The wheat homoeologous Group 5 chromosomes were characterized physically in terms of rice linkage blocks using a deletion mapping approach. All three chromosomes, 5A, 5B, and 5D, were shown to have a similar structure, apart from the 4A-5A translocation on the distal end of chromosome arm 5AL. The physical mapping of rice markers on the deletion lines revealed that the whole of rice chromosome 9 is syntenous to a large block, proximal to the centromere, on the long arm. Likewise, a small segment of the distal end of the long arm showed conserved synteny with the distal one-third end of the long arm of rice chromosome 3. In between those conserved regions, there is a region on the long arm of the Group 5 chromosomes which shows broken synteny. The proximal part of the short arms of the Group 5 chromosomes showed conserved synteny with a segment of the short arm of rice chromosome 11 and the distal ends showed conserved synteny with a segment of rice chromosome 12. The physical locations of flowering time genes (Vrn and earliness per se) and the gene for grain hardness (Ha) on the Group 5 chromosomes were determined. These results indicate that comparative mapping using the deletion mapping approach is useful in the study of genome relationships, the physical location of genes, and can determine the appropriate gene cloning strategy.

Chromosome Mapping↗

PubMed1994

ACE inhibition and physical exercise: studies on physical work capacity, energy metabolism, and maximum oxygen uptake in well-trained, healthy subjects.

We investigated the effects of the angiotensin-converting enzyme (ACE) inhibitor trandolapril (2 mg/o.d.) on the physical work capacity (PWC), the received perception of exertion (RPE), as well as parameters determining physical performance (i.e., energy metabolism, lactate production, and oxygen uptake) in well-trained, healthy subjects. Twenty male sports students underwent a bicycle spiroergometry until exhaustion to determine maximum work load, maximum oxygen uptake, lactate threshold, and parameters of energy metabolism. The identical protocol was repeated after a 14-day treatment period with 2 mg of trandolapril o.d. or placebo. Treatment with the ACE inhibitor did not significantly alter maximum PWC, RPE, 4.0 mmol/L lactate threshold, heart rate, maximum oxygen uptake, plasma levels of total cholesterol, triglycerides, free fatty acids, glucose, insulin, cortisol, and human growth hormone. In the presence of the ACE inhibitor, the exercise-induced increase in systolic blood pressure was moderately (n.s.) blunted (204 +/- 7 versus 192 +/- 7 mm Hg). Treatment with the ACE inhibitor did not impair physical performance and RPE. This favorable profile of action was accompanied by no alterations in maximum oxygen uptake and parameters of energy metabolism at all levels of exercise intensity. Therefore, it may be concluded that antihypertensive treatment with an ACE inhibitor should be primarily considered in physically active patients.

Adult↗

PubMed1975

Biological age and habitual physical activity in relation to physical fitness in 12- and 13-year-old schoolboys.

PURPOSE: The purpose of this study was to investigate the relationship between biological age, habitual physical activity and anthropometrical and physiological characteristics in 12- and 13-year-old schoolboys (n = 70). METHODS: At the beginning and the end of the school year 1971/2 biological age was determined by measuring skeletal age from left hand X-ray photographs. Habitual physical activity was determined by questionnaire interview and pedometers. RESULTS: All anthropometrical characteristics showed significant correlations (P less than 0.05) with skeletal age except for bicipital and tricipital skinfolds. Out of 9 physical fitness tests handgrip was the only test that showed a significant correlation (0.52) with skeletal age. Pedometer scores gave significant negative correlations (P less than 0.05) with anthropometrical characteristics except for tricipital skinfold. The fitness tests bent arm hang, 12 min run walk, sit and reach and W-170 showed significant correlations (P less than 0.05) with pedometer scores.

Activities of Daily Living↗

PubMed1996

How much physical activity should we do? The case for moderate amounts and intensities of physical activity.

A sedentary and unfit way of life leads to increased risk for several chronic diseases and premature mortality. Sedentary and unfit individuals are also more likely to develop functional limitations as they age. The precise type, amount, and intensity of physical activity required for protection needs further investigation. Traditional exercise recommendations suggest a threshold of activity that is necessary for protection, although current evidence does not support a dichotomous view of this issue. Clinical and epidemiological studies show a continuous dose-response gradient of outcome variables across a wide range of activity or fitness levels. Moderate amounts and intensities of physical activity are associated with improved health and reduced risk of morbidity and mortality when compared with low activity or fitness. The major public health emphasis for physical activity recommendations and programming should be to encourage the most sedentary and unfit 20 to 25% of the population to become at least moderately active, and this can yield substantial benefits for the population.

Exercise↗

PubMed2000

Comparative effects of two physical activity programs on measured and perceived physical functioning and other health-related quality of life outcomes in older adults.

BACKGROUND: Although inactivity is an important contributor to impaired functioning and disability with age, little is known concerning how improvements in physical functioning and well-being in older adults vary with the type of physical activity undertaken. METHODS: One hundred three adults age 65 years and older, recruited via population-based methods, were randomized to 12 months of community-based, moderate-intensity endurance and strengthening exercises (Fit & Firm) or stretching and flexibility exercises (Stretch & Flex). A combination of class- and home-based exercise formats was used. Measured and self-rated physical performance along with perceived functioning and well-being were assessed pre- and postintervention. RESULTS: Fit & Firm subjects showed greater 12-month improvements in both measured and self-rated endurance and strength compared to Stretch & Flex subjects. Stretch & Flex subjects reported greater improvements in bodily pain, and Stretch & Flex men evidenced greater improvements in flexibility relative to Fit & Firm subjects. Although overall exercise adherence was high in both exercise conditions (approximately 80%), subjects in both conditions showed better adherence to the home- versus class-based portions of their exercise prescriptions. CONCLUSIONS: Community-based programs focusing on moderate-intensity endurance and strengthening exercises or flexibility exercises can be delivered through a combination of formats that result in improvement in important functional and well-being outcomes. This represents one of the first studies to report significant improvements in an important quality of life outcome-bodily pain-with a regular regimen of stretching and flexibility exercises in a community-based sample of older adults.

Activities of Daily Living↗

PubMed1980

Ethical issues in physical therapy practice. A survey of physical therapists in New England.

This survey was an attempt to identify which ethical decisions are most frequently encountered and are most difficult to make for practicing physical therapists. A questionnaire that described 30 situations with an ethical dimension was sent to 450 American Physical Therapy Association members practicing in New England. A total of 187 (41.5%) usable questionnaires was returned. Issues raised by items were designated as primary, secondary, or nonpriority. Seven primary and 11 secondary ethical issues were identified. In brief, these issues involve the decision about which patients should be treated, what obligations are entailed by that decision, who should pay for treatment, and what duties derive from the physical therapist's relationship; with other health professionals, including physicians. Some of these decisions are more frequent in certain types of employment facilities than in others. Sources of ethical conflict and the role of the professional organization in defining moral values for the profession are discussed in this paper, and implications for education are presented.

Bioethical Issues↗

PubMed1976

Changes in muscle fibre size and physical performance in patients with rheumatoid arthritis after short-term physical training.

Ten patients with rheumatoid arthritis of moderate severity were given 6 weeks' intense physical training. During the investigation period the patients improved their physical performance capacity as well as their rate of perceived exertion. There was an increase in the muscle fibre size, of type I and type II, most pronounced in the latter fibre group. No 'flare-up' of the arthritis could be seen during the training period. Comments are made as to which patients might benefit by a short-term physical training.

Adult↗

PubMed1988

Physical fitness, physical activity and blood pressure in children.

In numerous studies the relationship between physical fitness, physical activity and blood pressure have been evaluated. However, only a minority of the reported studies are controlled. This report gives a review of cross-sectional studies in children and longitudinal dynamic training studies in young adults below the age of thirty dealing with physical fitness/physical activity and blood pressure.

Adolescent↗

PubMed1993

[Hygienic principles of physical load standardizing in physical education of school children].

The paper outlines the hygienic principles of standardizing exercises in schoolchildren's physical training. Proceeding from the optimal (proper) daily body's energy requirements, including organized physical activities, the authors propose a method of their determination. The proper values of daily energy requirements are defined from their ratio to rated maximum values by the maximum oxygen consumption. This ratio is independent of age and sex and accounts for about 20%. While comparing the actual daily energy uptake with the proper ones, their deficiency and excess is determined, which will make the optimum individual and group-specific (age-sex) standardization of exercises in schoolchildren's physical training.

Adolescent↗

PubMed1993

The physical condition of elderly women differing in habitual physical activity.

In a cross-sectional study, 50 elderly women (age 71.5 +/- 4.2 yr, mean +/- SD) participated in a battery of tests assessing several aspects of physical fitness. The women were selected based on tertiles of habitual physical activity as determined by a validated questionnaire 10 months ago. The tests comprised the following measurements: peak expiratory flow, flexibility of shoulder joint, flexibility of hip and spine, balance, reaction time, grip strength, manual dexterity, and endurance. Additionally, data were collected on height, body weight, and systolic and diastolic blood pressure. A questionnaire was used to evaluate subjective fitness and general subjective health. Results indicated that physically more active elderly women tend to have better results on most tests. Body weight and body mass index, flexibility of the hip and spine (assessed using a sit-and-reach test), and endurance on a walk test were significantly better in the more active women. Test results are confirmed by subjective evaluation by the participants.

Aged↗

PubMed1993

The effect of command emphasis and monthly physical training on Army physical fitness scores in a National Guard Unit.

Individual fitness, an important component of combat readiness, has been found to be deficient in some Reserve Component units of the United States Army. We evaluated a program of monthly physical training in an environment of increasing emphasis on unit physical fitness in an effort to determine the effect on unit performance on the semi-annual Army Physical Fitness Test (APFT). This program was examined in a retrospective manner to establish its effectiveness over a 6-month period. No statistically significant improvement in APFT scores could be found over the course of the study, suggesting that such a program is not an efficient means of improving unit fitness in the Reserve Components of the United States Army.

Adult↗

PubMed1996

Physical capacity and physical strain in persons with tetraplegia; the role of sport activity.

To determine the relationship between sport activity and physical capacity (PC) and physical strain (PS) during standardized activities of daily living (ADL), 25 subjects with tetraplegia were studied. To quantify PC, maximal power output, peak oxygen uptake and maximal isometric force were determined on a stationary wheelchair ergometer. PS was described as the highest heart rate (expressed as a percentage of the heart rate reserve), observed during standardized ADL tasks. Multiple regression analyses showed that sport activity, lesion level and completeness of the lesion were the most important determinants of PC. An inverse relationship was found between PS during the ADL tasks and parameters of PC. Parameters of PC and sport activity were significant determinants of PS. It is concluded that a higher PC is associated with a lower PS in daily life, and that sport activity is an important determinant of PC. Although no causal relationships could be established, due to the cross-sectional character of this study, the results support the assumption that being physically active is highly important for individuals with tetraplegia.

Activities of Daily Living↗

PubMed2000

Measurement of physical activity, exercise, and physical fitness in children: issues and concerns.

Data to support the type and level of physical activity that are necessary for health benefits in children and for later prevention of disease as adults are not available. This lack of information may be caused by inconsistency in terminology and by issues and concerns with available instruments to measure the concept. The purpose of this article is to address measurement issues related to physical activity/exercise or physical fitness in children. Implications of these issues for researchers and practitioners are discussed.

Adolescent↗

PubMed1999

The physical imperative in circadian rhythm: a cytoskeleton-related physically resettable clock mechanism hypothesis.

Organisms maintaining circadian rhythmicity are responding to physical constraint of a 24-hour cycle. Time-cue sensing is fundamental to the clock existence, and entrainment of circadian rhythm is indeed accessible to a wide variety of geophysical stimuli. Light-dark and temperature changes are the main time-cues. Additional physical forces such as barometric pressure, electrostatic and electromagnetic fields and gravity force, display a daily cyclic behavior and can function as secondary time-cues. A conceptual framework that contains explanations to all circadian properties including cell autonomous, environmental responsiveness and self-sustained character, is still lacking. It is argued that clock responsiveness to external cues is central to the cellular clock mechanism, and therefore, the nature of the time-cues and the pathways that enable the cell to respond to physical stimuli are of central importance. A role for cytoskeleton in clock entrainment mechanism is suggested in light of cytoskeleton's major involvement in cellular mechanotransduction.

Animals↗