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A view on the science: physical anthropology at the millennium

EDITOR'S NOTE The year 2000 marks the onset of the 21(st) century. In this transitional year, prominent physical anthropologists will provide brief reflections on our discipline, including what attracted them to it, and their views on the directions our discipline may pursue as we enter, in January 2001, the third millennium. Copyright 2000 Wiley-Liss, Inc.

Journal Article↗

Hemodynamics before and after physical endurance training in patients with myocardial infarction under various physical and psychomotor stress tests.

This hemodynamic study was done in 23 post myocardial infarction patients. The peripheral and central hemodynamics were examined by repeated ergometer tests, heart volume estimations, and heart catheterizations under various provocative techniques such as dynamic bicycle ergometer load, static hand grip load, volume load, atrial pacing, and psychomotor stress. After a 5-week period of endurance training we found a marked and statistically significant increase (40%) of maximal work tolerance and a significant decrease (10%) in heart rate and atrial blood pressure at rest and on equal levels of work load. No significant influence was seen on central (pulmonary) pressure readings at rest or on equal levels of work load beside the higher venous oxygen extraction. These peripheral effects of physical training were seen for all provocative tests, and also for those which were not trained as static and volume load and psychomotor stress.

Blood Pressure↗

The effect of type of physical activity measure on the relationship between body fatness and habitual physical activity in children: a meta-analysis.

BACKGROUND: The relationship between activity levels and body fat in children is unclear, despite a large number of studies. The issue is clouded by the wide variety of methods used to assess children's activity levels. It is important to assess whether the type of activity measure influences the fatness-activity relationship. This is a first step to uncovering the role of modifying variables such as gender, age, maturity, etc. PRIMARY OBJECTIVE: This study uses meta-analytic procedures to synthesize the results of such studies and to assess whether the type of activity measure used has an effect on the strength of the relationship observed. METHODS AND PROCEDURES: Fifty studies were located that satisfied the inclusion criteria. Seventy-eight per cent of the studies showed a negative relationship, 18% no relationship and 4% a positive relationship between physical activity and body fatness. Data were analysed using the meta-analytic procedures described by Rosenthal (Meta-analytic Procedures for Social Research, Sage, 1991). MAIN OUTCOMES AND RESULTS: The mean effect size indicated a small to moderate, inverse relationship (r = -0.16). Mean effect sizes differed significantly (F(3,52) = 8.04, p < 0.001) according to the activity measure used: questionnaire, r = -0.14; motion counters, r = -0.18; observation, r = -0.39; heart rate (HR), r = 0.00. Observation measures elicited a significantly stronger relationship with body fat than did questionnaire or heart rate measures (p < 0.05). However, there was no significant difference between the effect sizes elicited by observation and motion counters. Correlational analyses revealed no effect of age group or gender on the strength of the relationship between fatness and activity. CONCLUSIONS: This meta-analysis suggests there is a small to moderate relationship between body fat and activity in children. It is important to note, however, that the size of the relationship depends on the activity measure used. It is therefore recommended that direct measures of movement, such as observation or motion counter methods, are used to assess the relationship of activity levels with health.

Activities of Daily Living↗

Physical activity in physical education: teacher or technology effects.

This study assessed if wearing a heart rate monitor influenced student activity levels in elementary physical education. Data were analyzed for 4 students using an alternating treatment design to assess differential effects between accelerometer activity counts obtained from students when wearing the heart rate monitor and when they were not wearing the monitor. Results show that (a) there was no difference in activity counts between the 2 conditions, (b) boys had higher means than girls, and (c) the variance between more and less active boys was greater than the variance among the girls.

Child↗

Effects of physical exercise for elderly patients with physical impairments.

Exercise is known to preserve many physiological responses in the healthy elderly, yet those with physical impairments are often discouraged from exercising. The authors studied the effects of a closely supervised exercise program designed specifically for elders with health problems and functional limitations. Tests, selected for their relevance to clinical patient management, included the Self Evaluation of Life Function questionnaire, treadmill performance, and tests of autonomic nervous system and neuromotor functions. Ambulatory volunteers, aged 64 to 83 years, with noncardiac health problems, were randomly assigned to a control group (CG; n = 17) or a 16-week exercise group (EG; 3 hr/wk, n = 18). Nine of the control and 13 of the exercise subjects completed the study. All EG dropouts were due to illness. EG attendance averaged 87%, and subjects trained at a heart rate (HR) of 103 +/- 5 beats/min (SD) (98% of prescription HR). Though EG test responses showed a tendency to improve, none reached statistical significance. This result was affected by the small number completing the study and the variability inherent in such a sample. Though these impaired elderly subjects enthusiastically and safely participated with high attendance and at an exercise intensity adequate to expect benefit, measurable training effects were not demonstrated.

Aged↗

AAPM/RSNA physics tutorial for residents: fundamental physics of MR imaging.

Learning the basic concepts required to understand magnetic resonance (MR) imaging is a straightforward process. Although the individual concepts are simple, there are many concepts to learn and retain simultaneously; this situation may give the illusion that learning the physics of MR imaging is complicated. It is important for the radiologist who interprets MR images to understand the methods used to create the images because image contrast specifically depends on how the image data were acquired. Initial concepts include formation of magnetic fields from electric currents in loops of wire, the resonance phenomenon, the hydrogen proton and its frequency of precession, and absorption of radiofrequency energy. These concepts can then be applied to learn about T1 and T2 relaxation and contrast and how the acquisition parameters of echo time and repetition time can be used to achieve these image contrasts. Basic pulse sequences include the spin-echo, multiecho spin-echo, turbo spin-echo, inversion-recovery, and gradient-recalled-echo sequences.

Internship and Residency↗

High density lipoproteins (HDL) and physical activity: the influence of physical exercise, age and smoking on HDL-cholesterol and the HDL-/total cholesterol ratio.

220 trained men, examined the day before participation in a cross country ski-race, had significantly higher HDL-cholesterol and HDL-/total cholesterol ratio than untrained men, but did not differ signficantly from untrained women. HDL-cholesterol was significantly higher in skiers above 60 years than in skiers of younger age. Tobacco smokers ahd lower HDL-cholesterol and HDL-/total cholesterol ratio than non-smokers, but the differences were only significant in skiers, not in controls. HDL-cholesterol was positively correlated to total cholesterol in skiers. The HDL-cholesterol level may possibly contribute to the lower morbidity of CHD in men who are physically active during leisure time.

Adolescent↗

[Physical work capacity and oxygen requirements of rats during physical exertion following prolonged hypokinesia].

The white rats exposed to 60 and 100 day hypokinesia showed a substantial and progressive decline in the tolerance to a maximum physical load. This was accompanied by disorders in the regulation of the oxygen balance: during load oxygen requirements were mainly met by the oxygen debt. The above changes that followed a 100 day hypokinesia returned to the normal two months later.

Adaptation, Physiological↗

[Effects of the combination of nitrogen baths and physical training on physical performance and extrasystole in patients with coronary heart disease with intraventricular blocks].

99 patients with coronary heart disease (CHD), stable angina pectoris (functional class I-II), intraventricular blocks (IVB) took a course of general artificial nitrogen baths. Of them, 31 patients took the baths alone; 35 patients, in addition, exercised on veloergometer; 33 patients took baths and continued physical training up to 6 months. The results of the treatment were assessed with spiroveloergometry, ambulatory Holter ECG monitoring. Those who took baths and exercised for 6 months benefited from the treatment most as their muscular performance and coronary heart reserve increased; mean daily number of ventricular extrasystoles reduced by 73.3%, supraventricular extrasystoles--by 72.2%; intraventricular conduction was not damaged.

Angina Pectoris↗

[Effect of combined application of nitrogen baths and 6 month physical training on physical work capacity and extrasystole in patients with ischemic heart disease and stable stenocardia].

AIM: To study effects of combined use of general artificial nitric baths and bicycle exercise for 6 months on physical performance (PP) and extrasystole (ES) in patients with coronary heart disease (CHD) and stable angina pectoris (SAP) of functional class I-II. MATERIAL AND METHODS: A total of 129 CHD with SAP patients entered the study. Of them, 44 patients received balneotherapy (a course of general artificial nitric baths); 37 patients took the baths and exercised on bicycle ergometer; 48 patients took the baths, exercised on bicycle ergometer in the outpatient clinic and continued the exercises for 6 months. The patients were examined with spiroveloergometry and ambulatory Holter ECG monitoring. RESULTS: The latter group of patients achieved the highest training effect manifesting with increased PP and coronary heart reserve, an antiarrhythmic effect (a 73.3% fall in the mean number of ventricular ES for 24 hours, a 72.2% one in this number of supraventricular ES). CONCLUSION: A significant efficacy is shown of combined use of general nitric baths and bicycle exercise with prolongation for 6 months in CHD patients and SAP of functional class I-II with ES.

Angina Pectoris↗

Let's get physical: a policy on increasing physical activity in school-aged children.

Childhood obesity has reached epidemic proportions. One of the major reasons is the lack of physical activity due to time spent watching television or using computers. This lack coupled with poor dietary habits has led to significant increases in the number of children with Type II diabetes and predisposition to hypertension, coronary artery disease and others. Physicians can help reduce this trend.

Adolescent↗

[Physical work capacity studied by measured physical loading in patients with hereditary hemochromatosis].

A significant decrease of work fitness was revealed in 23 patients with verified diagnosis of hereditary hemochromatosis exposed to graded physical exercise. It is assumed that the decrease of exercise tolerance in these patients may be most possibly accounted for by the lowering of myocardial contractility as a result of its injury due to iron overload. It is not excluded, however, that nonspecific dystrophic processes determined by diabetes mellitus, liver damage and coronary atherosclerosis in some cases may develop.

Adult↗

The value of the physical examination in the diagnosis of anemia. Correlation of the physical findings and the hemoglobin concentration.

Certain clinical findings, such as pallor of the conjunctivae, nail beds, lips, oral mucosa, and palmar creases have traditionally been used by physicians in the diagnosis of anemia. We prospectively examined 50 patients to determine whether there was any correlation between these clinical findings and hemoglobin concentration. We noted a statistically significant correlation between hemoglobin concentration and the following: color tint of the lower eyelid conjunctiva, nail-bed rubor, nail-bed blanching, and palmar crease rubor. Results from our study support the contention that the presence and degree of anemia can be estimated clinically by careful physical examination.

Anemia↗

Stroke treatment: comparison of integrated behavioral-physical therapy vs traditional physical therapy programs.

This was a controlled study of the efficacy of two forms of therapy on upper limb functions of hemiparetic patients--one heavily behavioral and the other based on Bobath therapeutic exercises. It arose from an earlier pilot study comparing EMG biofeedback with physical therapy from which it was concluded that both the elapsed time since the acute stroke and the severity of residual disability were particularly important factors. Of 29 patients included and randomly assigned to one or the other heavily systematized therapies, 18 were classified as having early-severe and 11 as late-mild conditions. Multiple function tests by a "blinded" special technician in another location revealed that overall both forms of therapy obtained worthwhile clinical and statistical improvement, which was maintained at nine-month recheck testing; but there was no statistically significant superiority of one therapy over the other under the very specific circumstances of the research design. Ease of delivering care and other socioeconomic considerations become important factors in choosing either or both of these methods.

Adult↗

Relationship between energy expenditure, expressed as the physical activity index, and body weight at low physical activity programmes.

The physical activity index, PAI, is defined as the energy expenditure, EE, divided by the resting metabolic rate, RMR. An expression for the body weight dependency of PAI, ie, dPAI/dBW = K, is derived. Numerical values for this coefficient were calculated on the basis of six published papers using whole-body calorimetry with observations over 24 h. It was found to be around -0.0022 per kg body weight difference in the PAI range between 1.25 and 1.70.

Body Weight↗

Patellofemoral disorders: physical and radiographic evaluation. Part I: Physical examination.

Patellofemoral disorders present a diagnostic and therapeutic challenge to the orthopedic surgeon. By the sequential application of such basic diagnostic tools as inspection, palpation, and various measurements to a patient in standing, sitting, supine, and prone positions, a reproducible, comprehensive physical examination of the patellofemoral joint and entire lower extremity may be achieved.

Femur↗

[The use of involuntary commitment and other compulsory treatment in psychiatry. A study of registered compulsory treatment, physical restraint and the use of physical force].

The study covers nine psychiatric hospitals in Denmark that together account for 20% of all admissions to mental hospitals in the country. The period of investigation was from 1. January 1990 to 31. December 1991. Compulsory treatment, mechanical restraint and physical coercion were investigated. The number of patients that are submitted to compulsory treatment is relatively small compared to the total number of patients admitted to psychiatric hospitals. The use of the different kinds of coercion may among other factors depend upon the severity of the patient's disease, the bed occupancy and the amount of staff available including the number of doctors. The study shows differences among the participating departments in the use of mechanical restraint with wrist and/or ankle cuffs but not with a waist-belt. This may depend more upon different traditions on the wards than upon demographic differences. According to Danish law a doctor must attend a patient experiencing mechanical restraint. In an emergency situation the staff are permitted to effectuate the restraint without the doctor being present but a doctor must see the patient immediately afterwards and sign a protocol. This was the case in only about one third of all cases.

Adult↗