Physical Task Performance Research Articles

Antiaging treatments have been legally prescribed for approximately thirty years.

There is an interesting divergence between the achievements of geriatrics and gerontology. On the one hand, during the last 30 years physicians in many developed countries have successfully prescribed several medicines to cure various symptoms of senescence. On the other hand, the influence of such medicines on human life span practically has not been studied. The most common of the relevant medicines are nootropic piracetam, gamma-aminobutyric acid (GABA), selegiline, Ginkgo biloba, pentoxifylline, cerebrolysin, solcoseryl, ergoloid, vinpocetin, sertraline, and estrogens, among others. Available data from human clinical practices and experimental animal studies indicate that treatments with these drugs improve learning, memory, brain metabolism, and capacity. Some of these drugs increase tolerance to various stresses such as oxygen deficit and exercise, stimulate the regeneration of neurons in the old brain, and speed up the performance of mental and physical tasks. This means that modern medicine already has "antiaging" treatments at its disposal. However, the influence of such treatments on the mean and maximal life span of humans, and on the age trajectory of a human survival curve has been poorly studied. The increase in human life expectancy at birth in the second half of the last century was mostly caused by the better survival at the old and oldest old rather than at the young ages. In parallel, the consumption of brain protective and regenerative drugs has been expanding in the elderly population. We provide evidence in support of the idea that the consumption of medicines exerting antiaging properties may contribute to the increase in human longevity.

Differences in physical performance between men and women with and without lymphoma

Lee JQ, Simmonds MJ, Wang XS, Novy DM. Differences in physical performance between men and women with and without lymphoma. Arch Phys Med Rehabil 2003;84:1747–52. Objectives To describe and compare physical performance profiles in men and women with lymphoma with age- and gender-matched controls and to examine relationships among fatigue severity and physical performance in men and women with lymphoma. Design Case-control study. Setting Outpatient lymphoma service in a major cancer teaching hospital. Participants Fifty-one patients with lymphoma (26 women, 25 men), age- and gender-matched to 51 subjects without lymphoma. Interventions Not applicable. Main outcome measures A physical performance test battery consisting of a 50-ft (15-m) walk, a 6-minute walk, forward reach, repeated sit-to-stand, repeated reach-up, timed belt tie, sock test, and coin test. Patients also completed the Brief Fatigue Inventory (BFI). Results Multivariate analysis of variance was significant for main effects of group (F 8,89=27.12, P<.05) and gender (F 8,89=3.09, P<.05), and there was no significant interaction. Subsequent analyses found significant differences between groups and gender in the repeated reach-up task, forward reach, 50-ft walk, and distance walked in 6 minutes. Correlations among physical performance tasks and total BFI interference scores were moderate ( r range, .27–.43; P<.05) for tasks involving upper extremity, and stronger ( r range, .51 to −.73; P<.05) for tasks that involved whole-body movements. Conclusion There is a leveling effect of lymphoma across gender on most tasks. The significant relations between physical performance tasks and fatigue are suggestive of the pervasive influence of fatigue on physical function.

The Arthritis, Diet and Activity Promotion Trial (ADAPT): design, rationale, and baseline results

Osteoarthritis (OA) of the knee leads to restrictions of physical activity and ability to perform activities of daily living. Obesity is a risk factor for knee OA and it appears to exacerbate knee pain and disability. The Arthritis, Diet, and Activity Promotion Trial (ADAPT) was developed to test the efficacy of lifestyle behavioral changes on physical function, pain, and disability in obese, sedentary older adults with knee OA. This controlled trial randomized 316 sedentary overweight and obese older adults in a two-by-two factorial design into one of four 18-month duration intervention groups: Healthy Lifestyle Control; Dietary Weight Loss; Structured Exercise; or Combined Exercise and Dietary Weight Loss. The weight-loss goal for the diet groups was a 5% loss at 18 months. The intervention was modeled from principles derived from the group dynamics literature and social cognitive theory. Exercise training consisted of aerobic and strength training for 60 minutes, three times per week in a group and home-based setting. The primary outcome measure was self-report of physical function using the Western Ontario and McMaster University Osteoarthritis Index. Other measurements included timed stair climb, distance walked in 6 minutes, strength, gait, knee pain, health-related quality of life, knee radiographs, body weight, dietary intake, and cost-effectiveness of the interventions. We report baseline data stratified by level of overweight and obesity focusing on self-reported physical function and physical performance tasks. The results from ADAPT will provide approaches clinicians should recommend for behavioral therapies that effectively reduce the incidence of disability associated with knee OA.

Fear of pain, physical performance, and attentional processes in patients with fibromyalgia

Patients with fibromyalgia often present with increased levels of disability and physical functioning, for which the determinants are still unclear. In patients with other musculoskeletal pain syndromes, such as chronic low back pain, physical performance and disability levels are shown to be strongly associated with pain-related fear, and even stronger than pain severity. The present study was aimed at examining the role of pain-related fear and attentional processes on tolerance for physical activity in fibromyalgia patients. High and low fearful fibromyalgia patients ( N=81) were requested to perform a physical task, a cognitive (reaction time) task, and a dual task in which the physical and cognitive tasks were combined. It was hypothesized that high fearful patients would terminate the physical performance task sooner than low fearful patients, and would show a greater disruption on the cognitive task. In addition, it was expected that when distracted in the dual task, high fearful patients would show improved performance on the physical task after a fear reduction instruction. The results showed that pain itself was a greater predictor of activity tolerance than pain-related fear, but that pain-related fear was the stronger predictor of reaction times on the cognitive task. Also, all groups showed equal improvement in physical performance in the dual task. The findings suggest that baseline pain acts as an occasion setter which determines the level of physical activity the patient is willing to perform, regardless of pain increase and threat-reducing instructions.

Canadian Journal of Applied Physiology: Northern Highlights

MALE SOLDIERS WERE TESTED with an indoor 6-station obstacle course (OC) and a repetitive boxlifting task (RBLT). Performance in the more-complex OC stabilized on the third dual-trial test session, whereas that in the more simple RBLT stabilized on the second single-trial test session. These can be reliable tests, but only after initial sessions have provided the participants with test familiarization. The same would apply to other occupational physical performance tasks or physical fitness tests in which performance depends considerably on skill. Pandorf, C.E., et al. Reliability assessment of two military relevant occupational physical performance tests. Can. J. Appl. Phys. 28(1):27–37. 2003.

Body mass index and physical function in older women.

We modified existing standardized measurement tools in the Physical Performance Test and tasks from the Frailty and Injuries: Cooperative Studies of Intervention Technique Study to evaluate physical function in older women. Our objectives were (1) to characterize physical function themes based on combinations of tasks (deriving factors or components) and (2) to quantify the correlation between derived factors and body mass index (BMI). Nutrition risk screens from enrollees in a Medicare-managed risk program served as the sampling frame. To obtain adequate representation for a range of BMI, a random sample was obtained of 90 women from the following BMI strata: BMI, 22 to <27 kg/m(2); BMI, 27 to <30 kg/m(2); and BMI, > or =30 kg/m(2). Subjects were asked to perform a series of 18 functional tasks during a home visit. The mean age was similar in the three BMI groups with an overall mean age of 71 +/- 4.9 years (SD). Factors characterized by lower-body function, upper-body function, coordination, and strength were responsible for 30%, 11%, 9%, and 9% of the variance in task scores, respectively. BMI, controlling for age, explained 5%, 14%, 3%, and 0% of the variation in these factors, respectively. Higher BMI is associated significantly with poorer upper- and lower-body function but is not associated significantly to strength or coordination. Higher BMI seems to differentially impede specific aspects of physical function, especially upper-body function, and to a lesser extent, lower-body function. BMI does not seem to be associated with levels of coordination or strength. Better understanding of how BMI impacts physical function will aid in the design of interventions to promote independent living in elderly, obese women.

The Relationship of Group Process Variables and Team Performance

The efficacy of three group process variables—group potency, social cohesion, and team-member exchange—in explaining team performance was examined for 648 military officers working in 50 self-managed teams over a 5-week period. Team performance was assessed on two objective criteria (mental task performance and physical task performance) and one subjective criterion (commander team performance ratings). Each of the group process variables was related to at least one aspect of team performance. Of the three group process variables, group potency exhibited the greatest predictive efficacy as it explained unique variance in team performance over that accounted for by both social cohesion and team-member exchange.

Physical performance tasks: What are the underlying constructs?

Novy DM, Simmonds MJ, Lee CE. Physical performance tasks: What are the underlying constructs? Arch Phys Med Rehabil 2002;83:44-7. Objectives: To investigate the structural validity of a battery of physical performance tasks and to investigate the construct validity of the resulting factors. Design: A measurement study. Setting: A large, private orthopedic clinic and a physical therapy clinic in an urban area. Participants: One hundred three consecutive adult patients with low back pain who were referred for physical therapy assessment. Interventions: Not applicable. Main Outcome Measures: The physical performance battery was composed of the 50-foot speed walk, 5-minute walk, repeated trunk flexion, sit to stand, loaded reach, rollover tasks, and Sorensen upper-body lift. Participants also completed 5 self-report measures. Results: Two correlated (.74) factors, speed and coordination and endurance and strength, were derived from the physical performance tasks. The Sorenson upper-body lift task was the only indicator that was not useful in defining the factors. Both factors had statistically significant correlations with measures of physical disability, lack of self-efficacy, and negative affect. Both factors had a trivial correlation with a numeric rating of pain intensity. Conclusions: There is support for 2 meaningful empiric groupings (ie, the derived factors) of the performance tasks. Pain intensity had a trivial overlap with speed-coordination and endurance-strength factors. © 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Effects of Prolonged and Reduced Warm-Ups on Diurnal Variation in Body Temperature and Swim Performance

Previous studies have suggested a diurnal variation in the performance of physical tasks. The theoretical basis for the effect of time-of-day on performance centers on the circadian rhythms of many physiological variables and especially the body temperature curve. This investigation had two purposes: (a) to determine if increasing the volume of the warm-up could eliminate diurnal variation in body temperature and swim performance, and (b) to determine if reduction of the warm-up volume in the late afternoon would affect body temperature and swim performance. Participants for this investigation included 6 male and 4 female competitive swimmers (mean age = 15 +/- 1 years). Before the swim performance trials in the morning, participants warmed up with either standard volume (2,011.68 m) or 200% of that volume. Before the afternoon swim performance trials, warm-up volumes were either 33% or 100% of the standard warm-up volume. Before entering the water and immediately after the warm-up, temperature was taken from the ear. After the swim performance, participants were asked to rate their perceived exertion on the basis of Borg's CR-10 rating scale. The order of test administration for time of day and warm-up condition was balanced and with tests carried out over 4 days. Each swimmer completed 1 test condition (warm-up) per day. Results indicated that increased morning warm-up time eliminated diurnal variation in body temperature; however, evening superiority in swimming performance was not eliminated. The results also indicated that reducing the volume of the afternoon warm-up to 33% of the standard warm-up had no effect on body temperature or swim performance.

Evaluation of Different Scales for Measurement of Perceived Physical Strain During Performance of Manual Tasks

The main objective of this study was to evaluate different scales of perceived strain during the performance of various physical tasks. A total of 52 male and female participants took part in 4 experiments to achieve the study objective. The results suggest that a bipolar comfort-discomfort scale is a more appropriate instrument than a discomfort scale for assessing cumulative physical stresses at work, especially at the beginning of the shift. For assessing discomfort at the end of the work shift, a unipolar scale may also be used. On the basis of the obtained results, red, green, and yellow zones are suggested to establish priorities for work redesign efforts in ergonomic control programs.

Assessment of chronic pain behaviour: reliability of the method and its relationship with perceived disability, physical impairment and function.

The aim of the present study was to develop a reliable assessment of pain behaviour performed during the execution of a range of functional assessment measures. For the initial reliability study 18 subjects (consecutive referrals) were assessed. Subjects were observed and videotaped during a variety of physical tasks and demonstrations of pain behaviour were recorded; the videotapes were scored by two independent observers on two occasions. The relationships between pain behaviour, distress and physical function and impairment were also investigated in a group of 51 patients with chronic back pain. Self-report of disability and pain intensity were assessed using the Finnish version of Oswestry disability questionnaire and the pain visual analogue scale (VAS). Depression and somatic perception were assessed using the modified Zung and modified somatic perception questionnaire. The Tampa scale for kinesiophobia was used to evaluate fear of movement and (re)injury. The results of the intra- and interobserver reliability study demonstrate good to excellent levels of agreement. The exception was facial expression (kappa 0.29), which was excluded from the final instrument. There was a strong correlation between pain behaviour and subjective pain report and disability (p < 0.01). The correlations between total pain behaviour and performance of physical function tasks is striking (p < 0.01). Subjective disability was analysed by means of multiple regression analysis. Pain measured on the VAS was the most important variable explaining 36% of the variance, pain behaviour and pain combined explained 48% of the variance for self reported disability. In conclusion, this functional videobased assessment of pain behaviour is a reliable measure of pain behaviour. The total scores for pain behaviour correlate with tasks that involve the back; tests involving upper limbs were not affected. This test is suitable for the assessment of those with pain problems specifically involving the back. Furthermore, in the group studied pain and pain behaviour were the two most important determinants of self-reported disability.

EFFECTS OF PROLONGED AND REDUCED WARM-UPS ON DIURNAL VARIATION IN BODY TEMPERATURE AND SWIM PERFORMANCE

Previous studies have suggested a diurnal variation in the performance of physical tasks. The theoretical basis for the effect of time-of-day on performance centers on the circadian rhythms of many physiological variables and especially the body temperature curve. This investigation had two purposes: (a) to determine if increasing the volume of the warm-up could eliminate diurnal variation in body temperature and swim performance, and (b) to determine if reduction of the warm-up volume in the late afternoon would affect body temperature and swim performance. Participants for this investigation included 6 male and 4 female competitive swimmers (mean age = 15 +/- 1 years). Before the swim performance trials in the morning, participants warmed up with either standard volume (2,011.68 m) or 200% of that volume. Before the afternoon swim performance trials, warm-up volumes were either 33% or 100% of the standard warm-up volume. Before entering the water and immediately after the warm-up, temperature was taken from the ear. After the swim performance, participants were asked to rate their perceived exertion on the basis of Borg's CR-10 rating scale. The order of test administration for time of day and warm-up condition was balanced and with tests carried out over 4 days. Each swimmer completed 1 test condition (warm-up) per day. Results indicated that increased morning warm-up time eliminated diurnal variation in body temperature; however, evening superiority in swimming performance was not eliminated. The results also indicated that reducing the volume of the afternoon warm-up to 33% of the standard warm-up had no effect on body temperature or swim performance.

The effects of whole-body restriction on task performance

Many occupations, particularly involving maintenance operations, require individuals to perform both physical tasks and mental tasks in restricted spaces. Researchers have examined physical task performance under various restrictions; however, little research has investigated the effects of restricted space on cognitive tasks. Cognitive task performance in restricted spaces presents cognitive demands (i.e. the task itself) as well as additional physical demands (e.g. awkward postures), which may adversely affect task performance or operator workload. This research focused on the effects of whole-body restrictions on cognitive task performance. An experiment was conducted that examined 9 levels of restriction created in a laboratory: an unrestricted control, 6 single whole-body restrictions at two severity levels (2 lateral, 2 sagittal and 2 vertical) and 2 multiple restrictions (sagittal/vertical, lateral/sagittal/vertical). An inspection task served as the cognitive task. Behavioural, physiological and psychophysical measures were collected and analysed to measure the operator and performance effects. Operator response differences were found among the various forms of restriction as well as the severity level of similar forms of restriction. Increasing restriction significantly affected the behavioural and physiological operator response as opposed to the cognitive response.

Crowding, Performance, and Affect: A Field Experiment Investigating Mediational Processes1

Several mediating variables have been suggested for the effects of crowding on mental task performance. Among these are behavioral constraints imposed by crowds, mental overload, and loss of control. The present field experiment investigated the influence of crowding and providing information about the physiological effects of crowding on task performance and on affect, and the extent to which each of these effects is mediated by the 3 potential mediators. The results indicate that the effects of crowding on physical task performance were mediated by mental overload, and the effects on mental task performance and affect were mediated mainly by behavioral constraints. Directions for future research are suggested.

The Relationship between Functional Fitness and Coronary Heart Disease Risk Factors in Older Japanese Adults

In Japan, 2 approaches have been adopted to assess health and functional status in older adults. One is a battery of physical-performance tasks. The other is estimation of physical vitality using biomedical risk factors. Previous research has examined strength and direction of the relationship between functional fitness and performance on activities of daily living. Vital-age tests have most often been used to assess risk for developing a variety of age-related diseases. The present study examined interrelationships among functional fitness and vital-age scores in Japanese women (N = 129, mean age = 71.9). The functional fitness test battery consisted of arm curls, walking around 2 cones, moving beans with chopsticks, and functional reach. The vital-age test battery consisted of 6 coronary heart disease risk factors (systolic blood pressure, total cholesterol, low-density lipoprotein cholesterol, triglycerides, abdominal girth, and hematocrit) and 5 physical-performance variables (oxygen uptake and heart rate at lactate threshold, side-to-side stepping, 1-leg balance with eyes closed, and forced expiratory volume).

Physical performance: Differences in men and women with and without low back pain

Objective: To determine the extent to which there may be major differences in scores on a battery of physical performance tasks among men with nonspecific, mechanical low back pain (LBP), women with LBP, healthy men, and healthy women. Design: Case series survey. Setting: A referral-based orthopedic clinic. Patients: Thirty-three men and 46 women with LBP. Control Subjects: Twenty-one men and 25 women healthy controls. Intervention: Completion of six clinician-assessed physical performance tasks and self-report inventories. Main Outcome Measure: Performance scores on distance walked in 5 minutes, 50-foot walk at fastest speed, repeated sit-to-stand, repeated trunk flexion, loaded forward reach, and the Sorensen fatigue tasks. Results: Discriminant function analysis revealed that the four groups of subjects performed the physical tasks significantly different in two major ways: (1) healthy control subjects outperformed LBP patients, irrespective of gender, on tasks involving trunk control, coordination, and stability while with-standing heavy or quickly changing loads on the spine; (2) men outperformed women, irrespective of patient or nonpatient status, on tasks involving anthropometric features of limb length. The findings provide guidance on reasonable performance expectations for men and women patients with LBP. Future studies of treatment effectiveness also will be able to assess physical performance change in terms of the intersection between standards set by the men and women healthy control subjects and those of men and women patients. However, whether a return to nonpatient status is an appropriate treatment goal is left to future research.

Theoretical and Applied Aspects of Physical Ability Testing

5 Validity, the relationship between physical abilities and job performance, has been well established. Generally, there is an ascending and positive correlation between the possession of physical abilities and the performance of physical job tasks. The source of litigation in employment opportunity settings is frequently over the identification of a cut point, below which applicants are given no further consideration and above which the candidate is considered qualified. The three bodies of law (constitutional, statutory and administrative) do not clearly spell out what constitutes defensible criteria for the establishment of cut points. Since a task can not be made “fair,” test development specialists are frequently assailed when physical performance tests are demonstrated to have adverse impact against “protected classes.” The ideal test is reliable and valid by virtue of its relationship to frequently encountered or critical job demands. It is appropriately independent of skill (a trainable component of performance) and identifies on an objective, performance-related basis those individuals who possess high probability of success in their work versus those with critical deficiencies and propensities toward injury. The test should be safe to perform, relatively easy and economical to administer on a large scale by non-experts. Identification of relevant physical abilities, physical capacity testing including work sample and fitness/construct testing, and paradigms for the establishment of defensible cut points will be presented by the above authors.

FUNCTIONAL ASSESSMENT SCALES

The purpose of this study was to investigate disability in persons after traumatic brain injury (TBI) by using combinations of functional assessment item, subscale, domain, and full-scale scores to predict (1) the need for assistance in performance of specific physical care tasks measured in minutes of help per day provided by another person in the home and (2) the subject's level of satisfaction with life in general. This study also sought to account for the amount of supervision that persons with TBI may require beyond that needed for physical care tasks. The Functional Independence Measure (FIM) contributed to prediction of subjects' physical care needs. A single-point change in total FIM score was equivalent to an average of about 5 min of help from another person per day. Satisfaction with life in general was predicted mainly by the depression subscale of the Brief Symptom Inventory. However, this latter prediction was only true when subjects who required constant supervision were removed from analysis. Thus, the amount of supervision required by persons with TBI is an important variable to study in this population. Three categories of supervision were identified: constant (all of the time), periodic (daily or weekly), or not at all. The need for supervision and physical assistance from another person and a subject's satisfaction with life in general are important standards by which functional assessment instruments may be compared to reflect, in pragmatic terms, the impact of disability on the lives of individuals and on human and economic resources of the community.

Cardiovascular reactivity, Type A behavior, and coronary heart disease: Comparisons between myocardial infarction patients and controls during laboratory‐induced stress

Cardiovascular responses to a series of laboratory stressors were examined in middle-aged Type A and Type B men. The subjects were 30 patients with diagnosed myocardial infarction (NYHA Class 1) and 26 age-matched healthy controls. All subjects were nonsmokers in the normotensive range, and none were on medication. Blood pressure, heart rate, forearm blood flow and resistance, and impedance cardiography-determined response variables were obtained during performance and recovery periods of both mental and physical tasks. The patients showed elevated reactivity in systolic blood pressure and cardiac output and prolonged systolic time ratio during mental stress tasks and elevated total peripheral resistance and lower cardiac output and stroke volume during physical tasks, as compared with control subjects. Thus, the difference in blood pressure reactivity between patients and controls appeared to be primarily dependent on the vascular component during physical tasks, whereas the mental tasks promoted a hemodynamic response pattern more consistent with beta adrenergic activation. Type A men, irrespective of coronary status, showed larger systolic and diastolic blood pressure response to both mental and physical stress than did Type B men.

The Dimensions of Human Physical Performance: Factor Analysis of Strength, Stamina, Flexibility, and Body Composition Measures

Based on a review of the literature on exercise physiology and on factor analy- sis of individual differences in physical task performance, confirmatory and principal axis factor analyses were carried out on tests selected or designed to cover a wide range of physical abilities. Tests were selected to test certain hy- potheses about the nature and definitions of abilities accounting for individ- ual differences in physical task performance. Tests were administered to 206 subjects, ages 19-36, including 102 men and 104 women. The results confirmed earlier findings of Fleishman and his associates and clarified and ex- tended these earlier results regarding the nature and definition of physical abilities. The six-factor model supported included Static Strength, Dynamic Strength, Explosive Strength, and Bunk Strength, Stamina (cardiovascular endurance), and Flexibility. A common factor structure was found for men and women. Percent of body fat was found to relate to performance in some physical abilities (Sta...