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PubMed1995

Muscular endurance and flexibility components of the Singapore National Physical Fitness Award.

The selection of fitness tests for national fitness test batteries has been a major concern over the last decade in many countries. The present study examined muscular endurance and flexibility components of the Singapore National Physical Fitness Award (NAPFA) Scheme and compared the results with other similar fitness test protocols. A total of 286 subjects (149 males, 137 females) voluntarily participated and were divided into six age and gender groups. Significant correlations and no statistical differences (p < .05) were found between abdominal endurance using different protocols indicating that any of the alternative tests could be substituted for the NAPFA sit up test which has been classified as a contraindicated exercise (MacFarlane, 1993). In upper body muscular endurance tests, secondary age boys and all adults showed a high correlation (p < .01) with alternative test protocols. Replacement of the pull up test with the Vermont modified pull up test was recommended for primary and secondary boys because of the low number and many zero scores from the present NAPFA test. From this study it was concluded that the sit-and-reach test measured using a zero reference point from the floor could replace the present sit-and-reach test because the alternative protocol accounted for arm and leg differences. These findings provide safer and relevant alternative protocols for a national battery of field fitness assessments.

Abdominal Muscles↗

PubMed1977

Evaluation of the Canadian Home Fitness Test in middle-aged men.

The Canadian Home Fitness Test (CHFT) and the Bruce treadmill test were performed by 230 men aged 45 to 69 years. Because of inaccuracies in the counting of heart rates, less was known about the fitness of the men after testing than before. In addition, inaccuracies in the test record and design were uncovered. A more accurate estimate of fitness could be obtained when the subjects' own rating of exertional intensity was substituted for heart rate counting. The CHFT is a marketing tool of Health and Welfare Canada that may be useful in selling fitness, but as a measure of fitness in Canadian homes it is likely to be misleading.

Aged↗

PubMed1996

[Development of a functional fitness test for the elderly].

A test of functional fitness defined as physical capacity to independently perform daily functional activities was developed for aged persons. The functional fitness test was composed of four physical capacity evaluation tasks representing physical abilities necessary to perform main activities of daily living; viz. sitting and standing up test, zig-zag walking test, hand working test with pegboard for dexterity evaluation, and rope working test for self-care evaluation. The reliability and feasibility of the test were examined with 765 aged persons living in the community. The distribution of measurement values in each item showed neither extreme skewness nor kurtosis. Retest reliabilities for each task were 0.857 to 0.942, but the second trial showed significantly reduced (p < 0.001) values than the first trial in test-retest. Significant relationships (r = 0.503 to 0.627) between measurement values in each items and chronological age were found in both male and female. Functional fitness test and physical fitness test scores were correlated 0.740. These results showed that the functional fitness test developed in the present study has a high reliability and feasibility to evaluate functional capacity of daily living in aged persons.

Activities of Daily Living↗

PubMed1996

Endurance fitness and orthostatic tolerance.

BACKGROUND: Several lower body negative pressure studies conducted in recent years have suggested that aerobically fit individuals have poo-orthostatic tolerance (OT). HYPOTHESIS: There will be significant differences between OT of highly fit endurance runners and unfit individuals. METHODS: Subjects were 17 men and 17 women aged 29-42 yr who were administered two orthostatic tests (20 min standing) before, and 5 min following a VO2max test. There were 6 men and 6 women who were highly trained endurance runners with VO2max of 63 and 50 ml.kg-1.min-1 for the men and women, respectively; 6 men and 6 women had average fitness (VO2max of 40 and 32 ml.kg-1.min-1, respectively), and the remaining 5 men and 6 women had poor fitness (VO2max of 32 and 26 ml.kg-1.min-1, respectively). RESULTS: The trained men and women showed good OT before and after exercise, which was characterized by very low orthostatic heart rates (54 and 64 bpm before, 70 and 75 bpm after exercise, for the men and women, respectively); relatively large pulse pressures (PP); and a lack of any adverse subjective reactions. The untrained subjects' orthostatic heart rates were 30-40 bpm higher than in the trained subjects, (18 bpm higher after, vs. before exercise) their PP was narrower, and there were 7 cases of orthostatic weakness (dizziness, yawning) and 8 fainting episodes. (6 cases before, 9 cases after exercise). CONCLUSIONS: Aerobically fit individuals have good OT while unfit individuals show poor OT. Since the maintenance of good OT is important in the Space Shuttle flights, endurance training enhances crew/vehicle safety.

Adult↗

PubMed1997

Does physical fitness influence intraocular pressure?

The effects of physical fitness on intraocular pressure, was studied. The study was conducted in two parts. Part 1 consisted of three groups of physically fit subjects, each consisting of 50 subjects. In Part 2 subjects were categorized into control and experimental groups, each consisting of 16 subjects. The experimental group took a supervised exercise programme of three months. Intraocular pressure was measured with the Goldman applanation tonometer. As compared to sedentary subjects, intraocular pressures were lower in those who did moderate or severe exercises. In part one, the difference between group 1 consisting of sedentary and group 3 of physically fit subjects was 1.38 +/- 0.08 mmHg, (p < 0.001). In part two of this study, after exercise training the experimental group showed a marked increase in their physical fitness. The first difference between control and experimental groups was 0.13 +/- 0.27 mmHg (p > 0.05). After three months, this difference increased to 0.93 +/- 0.28 mmHg (p < 0.01). This study concludes that physical fitness reduces intraocular pressure. It would seem reasonable at present not to discourage patients who have glaucoma from light exercise, perhaps, on the contrary, it should be encouraged.

Adult↗

PubMed1976

Heart volume and physical fitness of parturients.

One hundred and three primigravidae were studied to establish the correlation between physical fitness and heart volume. Twenty-three of the mothers were allocated at random to the exercise group and 21 to control group 1, between the 10th and 14th weeks of pregnancy. In addition, 59 mothers were allocated to control group 2, which was formed two weeks before term. The exercise group underwent a rather strenuous training programme during pregnancy. Physical fitness was measured by work tests on a bicycle ergometer two weeks before term. The heart volume was determined radiologically on the 6th day post partum. There was a positive correlation between physical fitness and the relative heart volume, which was greatest when physical fitness was measured by a method which takes the level of training into consideration. The relative heart volume of the exercise group was almost significantly greater than that of control group 1. The physical performance of the exercise group was very significantly greater than in the control groups. There was no significant correlation between either physical fitness or relative heart volume and the duration of pregnancy or the weight of newborn.

Adult↗

PubMed1997

Long-term stability of fitting parameters with the COMBI 40.

Having experience with the COMBI 40 for over two years, it is now possible to look at the development of patient fittings over a longer period of time. In this study we look at patient fitting data (thresholds, dynamic ranges, etc.) at two days, one month, three months, six months and twelve months post first fitting. Subjects are CI-users participating in the COMBI 40 European Multicentric Study. Long-term fitting parameters show a favourable development. Stable fitting parameters and the safety features implemented in the COMBI 40 serve as a basis for a reliable long-term speech understanding.

Auditory Threshold↗

PubMed1976

Physical fitness levels vs selected coronary risk factors. A cross-sectional study.

Several studies show significant correlations of blood variables, weight, abnormal electrocardiograms, and blood pressure with the incidence of coronary heart disease, but the quantification of fitness and its correlation with coronary heart disease is more difficult. In this study, approximately 3,000 men, average age of 44.6 years, were examined for blood and lipid profile, pulmonary function, percent body fat determination, and Balke maximal performance treadmill stress testing with multilead ECG monitoring. Five age-adjusted cardiorespiratory fitness categories were determined from treadmill times. A consistent inverse relationship among physical fitness categories and resting heart rate, body weight, percent body fat, serum levels of cholesterol and triglycerides, glucose, and systolic blood pressure, was observed. Forced vital capacity was directly related to levels of fitness. These results, although cross-sectional, imply that physical fitness is related to lower coronary risk factors.

Adult↗

PubMed1998

Rigid gas permeable contact lens fitting after radial keratotomy.

PURPOSE: The purpose of our study was to determine whether radial keratotomy (RK) patients could be fit with rigid gas permeable (RGP) contact lenses based on postoperative keratometry measurements. METHODS: Thirteen eyes from eight post-RK patients were fit with RGP lenses for residual refractive errors. Since these patients were self-referred and were operated on elsewhere, preoperative keratometry readings were not available. We used postoperative keratometry readings for base curve selection; and spherical polymethylmethacrylate diagnostic lenses were used for fitting. RESULTS: Visual improvements averaged 3.85 Snellen lines (range: 1-8 lines). Prefitting visual acuities were: 20/30 (5 eyes); 20/40 (1 eye); 20/ 50 (1 eye); 20/60 (1 eye); 20/70 (3 eyes); 20/150 (1 eye); and 20/200 (1 eye). Final visual acuities were 20/20 (7 eyes), 20/25 (4 eyes), 20/30 (1 eye), and 20/40 (1 eye). CONCLUSION: We found that when fitting post-RK eyes with RGP contact lenses preoperative keratometry was unnecessary, and an empirical fitting method based on postoperative keratometry was successful.

Adult↗

PubMed1998

Physical activity, physical fitness, and risk of dying.

We examined the relation between physical activity, physical fitness, and all-cause mortality in a national population-based study of Canadians. We followed men and women ages 20-69 years who had participated in the Canada Fitness Survey between 1981 and 1988. We assessed risk factors for 6,246 men and 8,196 women using multivariate Poisson regression analysis. At baseline, all subjects were asymptomatic according to self-reported screening questions for cardiovascular disease. Men who expended > or =0.5 kilocalories per kilogram of body weight per day (KKD) experienced a 20% decline in risk of mortality [rate ratio (RR) = 0.82; 95% confidence interval (CI) = 0.65-1.04] when compared with subjects expending <0.5 KKD. We observed a 30% decline in risk of mortality among women expending > or =3.0 KKD relative to those expending <0.5 KKD (RR = 0.71; 95% CI = 0.45-1.11). Similar patterns of risk were evident for both men and women when analyses were restricted to participation in nonvigorous activities. Those who perceived themselves to be of less than average fitness were at increased risk of mortality (male RR = 1.64, 95% CI = 1.21-2.22; female RR = 1.66, 95% CI = 1.21-2.26). Subjects with undesirable cardiorespiratory fitness levels were more likely to die, compared with those having recommended fitness levels (RR = 1.52; 95% CI = 0.72-3.18). Fifty-three per cent of men and 35% of women reported participating in a vigorous activity. The relation between daily energy expenditure and risk of mortality in these subjects could not be evaluated, as there were few deaths. Nonetheless, our results among participants reporting no vigorous activities support the hypothesis that there is a reduction in mortality risk associated with even modest participation in activities of low intensity.

Adult↗

PubMed2026

Effects of an internet-based combined exercise and cognitive-behavioral therapy intervention on endocannabinoid system biomarkers and physical fitness in adults with mild-to-moderate depression: a SONRIE randomized controlled trial.

BACKGROUND: This SONRIE randomized controlled trial (NCT05849792) examined the effects of a 12-week combined physical exercise and internet-based cognitive-behavioral therapy (iCBT) intervention on endocannabinoid system (ES) biomarkers and physical fitness in adults with mild-to-moderate depression. METHODS: Eighty adults were randomly assigned 1:1 to an intervention (IG) or control (CG) group. Outcomes included nine ES biomarkers (2-arachidonoylglycerol, 2-AG; anandamide, AEA; seven analogues) and physical fitness, including cardiorespiratory fitness (CRF; 6-minute walking test) and muscular strength. Measurements were taken at baseline, post-intervention and 8-week follow-up. Primary analysis performed 2 × 3 repeated-measures ANOVA on completers; mixed-effects intention-to-treat model as sensitivity analysis. RESULTS: No significant time × group interaction was detected for any ES biomarker, including 2-AG (F(2,88) = 0.17, p = 0.844) and AEA (F(2,88) = 1.20, p = 0.306); both groups showed comparable within-group decreases in 2-AG, 2-LG and 2-OG. The intervention significantly improved CRF [between-group difference + 81.6 m at 12 weeks (F(2,78) = 7.88, p = 0.001)], exceeding the established minimal clinically important difference. None of the exploratory muscular fitness outcomes reached statistical significance; the arm curl test showed a borderline non-significant interaction (F(2,78) = 2.83, p = 0.065). CONCLUSION: A 12-week internet-based combined exercise and iCBT intervention significantly improved CRF in adults with mild-to-moderate depression. We did not find evidence of an intervention-specific effect on plasma ES biomarkers. These findings support the inclusion of internet-delivered exercise and psychological interventions in comprehensive treatment strategies for depression. TRIAL REGISTRATION: ClinicalTrials.gov NCT05849792 (registered 6 May 2023).

Humans↗

PubMed2026

Deconstructing empirical fitness seascapes across scales of granularity.

The fitness landscape metaphor remains resonant in evolutionary theory and has facilitated the birth of newer concepts, like the fitness seascape, that consider the role of environmental context in shaping the dynamics of evolution. Since its emergence, the seascape has appeared in numerous studies examining how different and fluctuating environments shape evolutionary outcomes. Despite growing interest, we lack comprehensive examinations of how environmental context shapes features of fitness seascapes. In this study, we address this gap by deconstructing empirical fitness seascapes across scales of granularity: loci, locus interactions (epistasis), alleles, trajectories, and entire seascapes. For each, we examine how environmental context influences qualitative and quantitative aspects of seascapes, and find that they change appreciably, with patterns specific to individual systems of study. We also quantify how much each scale varies across environments, and find that certain scales tend to be more sensitive to context than others. In summary, we reflect on the implications of the seascape metaphor for the incorporation of environmental effects into theoretical population genetics, for understanding how the environment shapes evolution in disease systems, and for contemporary bioengineering efforts.

Genetic Fitness↗

PubMed1999

Fitting cytosolic ADP recovery after exercise with a step response function.

Phosphorus magnetic resonance (MR) spectroscopy was used to measure the recovery kinetics of calculated cytoplasmic metabolically active adenosine diphosphate (ADP) after exercise in normal subjects and patients with mitochondrial myopathies. These kinetics have previously been fitted with a single exponential function, despite a complex time-dependent undershoot in many subjects. By considering the transition from ischemic-exercise to perfused-recovery as a step function input, a second-order linear system was developed yielding a step response function to fit the ADP recovery. Using this method, an average improvement in fit of 23% resulted in a significant improvement in the characterization of ADP recovery for all normal subjects with substantial undershoot. The patient group had a comparable improvement in fit of 11%. Fitting the ADP recovery with a second-order step response function can provide significantly better characterization of muscle oxidative metabolism in vivo.

Adenosine Diphosphate↗

PubMed2000

Is there a g factor for fitness?

Biological fitness is a directly observable quantity with well-known causal components, in contrast to the latent 'g' factor of psychometrics. The study of the causes of variation in fitness should therefore be simpler than the study of variation in mental abilities, but a paucity of data has kept the nature of genetic variation in fitness obscure. We can define an 'f' factor as variation creating positive correlations among components of fitness. There is little doubt that such f factor exist. Perturbations of populations such as mutation or environmental change create such patterns of positive correlation. However, natural selection will tend to minimize variation in any f factor, so it is much less clear whether f causes quantitatively substantial genetic variation within populations. Experimental data are consistent with variation in an f factor within some natural populations. As predicted, f is less important in populations where natural selection has had more opportunity to reshape the correlation matrix. Although one can incorporate variation in g into a study of variation in human fitness, the pace of change in our environment suggests that the results would neither reflect the conditions under which g evolved nor predict future evolutionary changes in g.

Factor Analysis, Statistical↗

PubMedDate not supplied

Comparison of fitting methods for the analysis of plasma concentration-time data resulting from constant rate intravenous infusion.

Plasma concentration-time data resulting from constant rate intravenous infusion may be analysed in two ways: Samples may be collected both during and after infusion and fit to an infusion model. Samples may be collected after infusion is complete and the data may be fit as an i.v. bolus. The purpose of this study was to contrast these two fitting procedures in terms of the accuracy of the parameter values obtained. Concentration-time data were computer-generated with the introduction of random error to simulate the disposition profiles of two model drugs. The results of these simulations indicate that satisfactory values for area-dependent parameters may be obtained without fitting data during the infusion phase. The exception to this is the apparent steady-state volume whose values become less accurate with longer infusion times. The parameters most affected by ignoring data points in the infusion phase are the central volume of distribution, and the coefficient and disposition rate constant associated with the initial, rapid phase of disposition. The equation which describes the entire concentration-time profile provides the most accurate parameter estimates of the model equation. In addition, we also describe the influence of the fitting method on the intercompartmental transfer rate constants.

Humans↗

PubMedDate not supplied

Application of time-domain fitting in the quantification of in vivo 1H spectroscopic imaging data sets.

Time-domain model function fitting techniques were applied to improve the reconstruction of metabolite maps from the data sets obtained from in vivo 1H spectroscopic imaging (SI) experiments. First, residual water-related signals were removed from the SI data sets by using SVD-based linear time-domain fitting based upon the HSVD (State Space) approach. Second, peak integrals of the metabolites of interest were obtained by quantifying the proton spin-echoes of the voxels by means of non-linear time-domain fitting based upon the maximum likelihood principle. Third, in order to save computational time, interpolation of the metabolite images (from size 32 x 32 to 128 x 128) was performed in the image-domain by applying one-dimensional cubic splines. It was found that the residual water signals can be almost completely removed from the SI data sets by applying the linear HSVD fitting method. Furthermore, it was found that voxel dependency of certain NMR parameters (e.g., variations of the spin-echo offset frequencies and/or phase factors) can be accounted for automatically by applying the nonlinear time-domain fitting technique. For that purpose it appeared to be essential to employ prior knowledge of the NMR spectral parameters.

Aspartic Acid↗

PubMed2002

Global goodness-of-fit tests in logistic regression with sparse data.

The logistic regression model has become the standard analysing tool for binary responses in medical statistics. Methods for assessing goodness-of-fit, however, are less developed where this problem is especially pronounced in performing global goodness-of-fit tests with sparse data, that is, if the data contain only a small numbers of observations for each pattern of covariate values. In this situation it has been known for a long time that the standard goodness-of-fit tests (residual deviance and Pearson chi-square) behave unsatisfactorily if p-values are calculated from the chi(2)-distribution. As a remedy in this situation the Hosmer-Lemeshow test is frequently recommended; it relies on a new grouping of the observations to avoid sparseness, where this grouping depends on the estimated probabilities from the model. It has been shown, however, that the Hosmer-Lemeshow test also has some deficiencies, for example, it depends heavily on the calculating algorithm and thus different implementations might lead to different conclusions regarding the fit of the model. We present some alternative tests from the statistical literature which should also perform well with sparse data. Results from a simulation study are given which show that there exist some goodness-of-fit tests (for example, the Farrington test) that have good properties regarding size and power and that even outperform the Hosmer-Lemeshow test. We illustrate the various tests with an example from dermatology on occupational hand eczema in hairdressers.

Beauty Culture↗

PubMed2004

A tree based lack-of-fit test for multiple logistic regression.

Several omnibus tests have been developed to assess the fit of a regression model. But many of these lack-of-fit tests focus on the simple regression setting. Here, we focus on multiple logistic regression. Pearson's well-known chi-square test statistic and the deviance statistic are no longer valid in the case that the model contains one or more continuous covariates. To overcome this difficulty, Hosmer and Lemeshow proposed a Pearson type statistic based on groups defined by the so-called deciles of risk. We propose a test statistic that is similar in approach to the Hosmer and Lemeshow statistic in that the observations are classified into distinct groups. In the procedure proposed here however, the grouping is not according to probabilities fitted under the null model. We use a recursive partitioning algorithm to divide the sample space into different groups. This generally allows for a more powerful assessment of the model fit. Simulations are carried out to compare the results of the proposed test to that of Hosmer and Lemeshow. Three data examples illustrate the performance of the tree based lack-of-fit test, in comparison to several other tests.

Adult↗