Functional fitness benchmark values for older adults: a systematic review.

Introduction: The use of normative values and/or standards of functional fitness in adults is relevant to overall health and well-being. The objectives of the study were: to identify the physical tests of the senior fitness test (SFT) that have been applied since its proposal and to describe the proposed percentiles according to age, sex and country. Methods: A systematic review study was conducted in the Pubmed and Scopus databases. As eligibility criteria, we considered the period from 1999 to 2022 that presented data on SFT test used in the population over 60 years of age and that described normative values through percentiles. MeSH were used as: (1) Physical fitness, Exercise test, Senior Fitness Test, Functional fitness, Cardiorespiratory fitness, (2) older adult, aged, (3) Reference standards, standards, standards of care. Boolean operators "AND" and "OR" were included. Data extracted from the selected studies included: year of publication, country, sample age, sample size, sample sex, fitness component. Results and discussion: Seven studies were identified in five countries (03 in China, 01 in Poland, 01 in Portugal, 01 in Spain and 01 in United States). The age range ranged from 60 to 103 years. The studies were conducted in both sexes. The study with the smallest sample size was by Chung et al. (China) with 944 participants and the largest number of participants was the study by Rikli and Jones in the United States with 7,183 participants. In general, no study was able to complete 100% (8 components) of the tests proposed in the SFT. Normative values were presented through percentile distribution (p10, p50 and p90) organized by age ranges. Males presented better performance in FPF tests than females in all tests. Since the first publication of the SFT until 2022, seven articles have been published in countries such as United States, China (three regional studies), Poland, Portugal and Spain. No study has published the complete battery with its eight components. The percentiles of functional fitness reflect decline with advancing age. Systematic review registration: PROSPERO (CRD42023441294: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023441294).

The Relationship Between Self-Efficacy and Functional Capacity Among Discharged Heart Failure Patients in Jordan.

BACKGROUND: Self-efficacy is an important factor associated with healthy lifestyle changes in heart failure treatment. Functional capacity testing of heart failure patients (HFPs) can stratify prognosis. Reduced functional capacities in HFPs are linked to a poor heart failure prognosis. Limited research has examined the potential relationship between self-efficacy and functional capacity. AIM: The aims of this study were to assess self-efficacy level and functional capacity among HFPs after hospitalization, and examine whether there is a relationship between them. METHODS: A descriptive correlational design was used. A convenience sample of 220 HFPs was recruited from 2 hospitals in Jordan. The Arabic version of Cardiac Self-Efficacy Questionnaire was used to assess self-efficacy, the 6-Minute Walking Test (6-MWT) was used to assess functional capacity, and the Borg rating of perceived exertion scale (Borg Scale) was used to assess exertion during 6-MWT. RESULT: The sample included 46.8% male (n = 103) and 53.2% female (n = 117). The mean age was 52.66 ± 8.91 years. Most of the HFPs were categorized based on New York Heart Association classification as class I, 35.9% (n = 79), and class II, 41.4% (n = 91). The mean ejection fraction was 41.46 ± 9.44. The global self-efficacy was moderate (32.98 ± 9.92), and the mean score for the 6-MWT was 494.35 ± 143.37. The Borg Scale mean was 10.94 ± 3.34. In addition, there was a positive relationship between self-efficacy and 6-MWT (r = 0.63, n = 220, P = .01). CONCLUSION: This study provides baseline data for further research on treatment of HFPs, and the development of evidence-based tailored health interventions to maintain and improve self-efficacy and functional capacity among these service users. Moreover, replicated researches can test the study results considering different methodologies, such as using objective functional capacity tool and longer follow-up periods.

A pulmonary rehabilitation program is an effective strategy to improve forced vital capacity, muscle strength, and functional exercise capacity similarly in adults and older people with post-severe COVID-19 who required mechanical ventilation.

BACKGROUND: It is internationally known that our population is aging. At the same time, some patients with COVID-19, due to their symptoms, required mechanical ventilation (MV) and subsequent pulmonary rehabilitation (PR). This study aimed to compare the effects of a multimodal PR program "ADULT" versus "OLDER" people with COVID-19 who were on MV. METHODS: The intervention consisted of an 8-week hybrid PR program (2x week). Forced vital capacity (FVC) was measured at the beginning and end of PR, upper and lower limb strength was obtained through hand grip strength (HGS) and the sit-to-stand test (STST), respectively, and functional exercise capacity was measured with the 6-minute walking test (6MWT). RESULTS: The main results were an increase in the FVC in the ADULT and OLDER groups (time effect, P = 0.000; η2 = 0.27), an increase in HGS in the ADULT and OLDER groups (time effect, P = 0.000; η2 = 0.52), in the same way, the number of repetitions on the STST increased in the ADULT and OLDER groups (time effect, P = 0.000; η2 = 0.55). Finally, the distance covered on the 6MWT increased in the ADULT and OLDER groups (time effect, P = 0.000; η2 = 0.65). CONCLUSIONS: The PR program is an effective strategy to improve FVC, muscle strength, and functional exercise capacity similarly in adults and older people with post severe COVID-19 who required MV.

The International Fitness Scale (IFIS): A valid tool to assess physical fitness in French children.

BACKGROUND: The need for monitoring regularly physical fitness in youth is well established for public health issues. The aim of this study was to assess the validity and reliability of the International Fitness Scale questionnaire (IFIS) to assess physical fitness in French children in the school context. METHODS: A sample of 2 060 children (1054 boys), aged 10.6 ± 0.9 years, participated in the validation study while an independent sample of 366 children (175 boys), aged 9 to 11 years, participated in the assessment of reliability. Physical fitness was measured by a self-report of 5 questions with a 5-point Likert-scale (from very poor to very good) (IFIS), and also measured objectively by 4 field tests: cardiorespiratory fitness, muscular strength, speed/agility and flexibility. For the test-retest reliability assessment, children were instructed to complete the questionnaire twice, 1 week apart. RESULTS: For all physical fitness components studied, children reporting a good or a very good physical fitness in the IFIS had better results in objective measurements of physical fitness tests compared to children reporting a very poor to an average physical fitness (p<0.001) without or with adjustments for sex, age and weight status. The reliability coefficients were acceptable for all components of physical fitness (0.59-0.72). CONCLUSIONS: These results suggest that IFIS appears to be a useful instrument for teachers to estimate physical fitness levels of French children, possibly on a large scale.

Abnormal heart rate responses to exercise in non-severe COPD: relationship with pulmonary vascular volume and ventilatory efficiency.

BACKGROUND: Despite being a prognostic predictor, cardiac autonomic dysfunction (AD) has not been well investigated in chronic obstructive pulmonary disease (COPD). We aimed to characterise computed tomography (CT), spirometry, and cardiopulmonary exercise test (CPET) features of COPD patients with cardiac AD and the association of AD with CT-derived vascular and CPET-derived ventilatory efficiency metrics. METHODS: This observational cohort study included stable, non-severe COPD patients. They underwent clinical evaluation, spirometry, CPET, and CT. Cardiac AD was determined based on abnormal heart rate responses to exercise, including chronotropic incompetence (CI) or delayed heart rate recovery (HRR) during CPET. RESULTS: We included 49 patients with FEV1 of 1.2-5.0 L (51.1-129.7%), 24 (49%) had CI, and 15 (31%) had delayed HRR. According to multivariate analyses, CI was independently related to reduced vascular volume (VV; VV ≤ median; OR [95% CI], 7.26 [1.56-33.91]) and low ventilatory efficiency (nadir VE/VCO2 ≥ median; OR [95% CI], 10.67 [2.23-51.05]). Similar results were observed for delayed HRR (VV ≤ median; OR [95% CI], 11.46 [2.03-64.89], nadir VE/VCO2 ≥ median; OR [95% CI], 6.36 [1.18-34.42]). CONCLUSIONS: Cardiac AD is associated with impaired pulmonary vascular volume and ventilatory efficiency. This suggests that lung blood perfusion abnormalities may occur in these patients. Further confirmation is required in a large population-based cohort.

Normative values in healthy adults for the 6-minute and 2-minute walk tests in Belgium and Vietnam: implications for clinical practice.

OBJECTIVE: To establish reference values for the 6-minute walk test (6MWT) and 2-minute walk test (2MWT) distances, to investigate the correlation between these 2 tests, and to establish prediction equations for these distances in healthy populations of Belgium and Vietnam. DESIGN: Cross-sectional study. SUBJECTS AND METHODS: The 6MWT and 2MWT were administered to a convenience sample of 239 Belgian and 303 Vietnamese participants between the ages of 18 and 80 years. RESULTS: The mean (standard deviation; SD) 2MWT distances were 215 (32.8) m for Belgian participants and 156 (25.5) m for Vietnamese participants. The mean (SD) 6MWT distances were 625 (90.7) m for Belgian participants and 449 (70.4) m for Vietnamese participants. The Pearson correlation coefficient between the 2 tests was 0.901 (p < 0.001) for Belgian participants and 0.871 (p < 0.001) for Vietnamese participants. Age and sex were the 2 most important predictors of walking distance, followed by body mass index for Belgium and height for Vietnam. The adjusted R² ranged from 0.31 to 0.49 across 4 predictive equations. CONCLUSION: These results can be used to determine the presence of walking performance deficits and to guide future studies. The 2MWT is suggested as a useful and convenient alternative to the 6MWT for assessing walking performance in clinical practice.

Inter- and intra-observer reliability and agreement of O2Pulse inflection during cardiopulmonary exercise testing: A comparison of subjective and novel objective methodology.

Cardiopulmonary exercise testing (CPET) is the 'gold standard' method for evaluating functional capacity, with oxygen pulse (O2Pulse) inflections serving as a potential indicator of myocardial ischaemia. However, the reliability and agreement of identifying these inflections have not been thoroughly investigated. This study aimed to assess the inter- and intra-observer reliability and agreement of a subjective quantification method for identifying O2Pulse inflections during CPET, and to propose a more robust and objective novel algorithm as an alternative methodology. A retrospective analysis was conducted using baseline data from the HIIT or MISS UK trial. The O2Pulse curves were visually inspected by two independent examiners, and compared against an objective algorithm. Fleiss' Kappa was used to determine the reliability of agreement between the three groups of observations. The results showed almost perfect agreement between the algorithm and both examiners, with a Fleiss' Kappa statistic of 0.89. The algorithm also demonstrated excellent inter-rater reliability (ICC) when compared to both examiners (0.92-0.98). However, a significant level (P ≤0.05) of systematic bias was observed in Bland-Altman analysis for comparisons involving the novice examiner. In conclusion, this study provides evidence for the reliability of both subjective and novel objective methods for identifying inflections in O2Pulse during CPET. These findings suggest that further research into the clinical significance of O2Pulse inflections is warranted, and that the adoption of a novel objective means of quantification may be preferable to ensure equality of outcome for patients.

Mechanisms of Exercise Intolerance Across the Breast Cancer Continuum: A Pooled Analysis of Individual Patient Data.

PURPOSE: The purpose of this study is to evaluate the prevalence of abnormal cardiopulmonary responses to exercise and pathophysiological mechanism(s) underpinning exercise intolerance across the continuum of breast cancer (BC) care from diagnosis to metastatic disease. METHODS: Individual participant data from four randomized trials spanning the BC continuum ([1] prechemotherapy [n = 146], [2] immediately postchemotherapy [n = 48], [3] survivorship [n = 138], and [4] metastatic [n = 47]) were pooled and compared with women at high-risk of BC (BC risk; n = 64). Identical treadmill-based peak cardiopulmonary exercise testing protocols evaluated exercise intolerance (peak oxygen consumption; V̇O2peak) and other resting, submaximal, and peak cardiopulmonary responses. The prevalence of 12 abnormal exercise responses was evaluated. Graphical plots of exercise responses were used to identify oxygen delivery and/or uptake mechanisms contributing to exercise intolerance. Unsupervised, hierarchical cluster analysis was conducted to explore exercise response phenogroups. RESULTS: Mean V̇O2peak was 2.78 ml O2.kg-1·min-1 (95% confidence interval [CI], -3.94, -1.62 mL O2.kg-1·min-1; P < 0.001) lower in the pooled BC cohort (52 ± 11 yr) than BC risk (55 ± 10 yr). Compared with BC risk, the pooled BC cohort had a 2.5-fold increased risk of any abnormal cardiopulmonary response (odds ratio, 2.5; 95% confidence interval, 1.2, 5.3; P = 0.014). Distinct exercise responses in BC reflected impaired oxygen delivery and uptake relative to control, although considerable inter-individual heterogeneity within cohorts was observed. In unsupervised, hierarchical cluster analysis, six phenogroups were identified with marked differences in cardiopulmonary response patterns and unique clinical characteristics. CONCLUSIONS: Abnormal cardiopulmonary response to exercise is common in BC and is related to impairments in oxygen delivery and uptake. The identification of exercise response phenogroups could help improve cardiovascular risk stratification and guide investigation of targeted exercise interventions.

Torque-Cadence Profile and Maximal Dynamic Force in Cyclists: A Novel Approach.

We aimed to determine the feasibility, test-retest reliability and long-term stability of a novel method for assessing the force (torque)-velocity (cadence) profile and maximal dynamic force (MDF) during leg-pedaling using a friction-loaded isoinertial cycle ergometer and a high-precision power-meter device. Fifty-two trained male cyclists completed a progressive loading test up to the one-repetition maximum (1RM) on a cycle ergometer. The MDF was defined as the force attained at the cycle performed with the 1RM-load. To examine the test-retest reliability and long-term stability of torque-cadence values, the progressive test was repeated after 72 h and also after 10 weeks of aerobic and strength training. The participants' MDF averaged 13.4 ± 1.3 N·kg-1, which was attained with an average pedal cadence of 21 ± 3 rpm. Participants' highest power output value was attained with a cadence of 110 ± 16 rpm (52 ± 5% MDF). The relationship between the MDF and cadence proved to be very strong (R2 = 0.978) and independent of the cyclists' MDF (p = 0.66). Cadence values derived from this relationship revealed a very high test-retest repeatability (mean SEM = 4 rpm, 3.3%) and long-term stability (SEM = 3 rpm, 2.3%); despite increases in the MDF following the 10-week period. Our findings support the validity, reliability and long-term stability of this method for the assessment of the torque-cadence profile and MDF in cyclists.

Confirming the attainment of maximal oxygen uptake within special and clinical groups: A systematic review and meta-analysis of cardiopulmonary exercise test and verification phase protocols.

BACKGROUND AND AIM: A plateau in oxygen uptake ([Formula: see text]) during an incremental cardiopulmonary exercise test (CPET) to volitional exhaustion appears less likely to occur in special and clinical populations. Secondary maximal oxygen uptake ([Formula: see text]) criteria have been shown to commonly underestimate the actual [Formula: see text]. The verification phase protocol might determine the occurrence of 'true' [Formula: see text] in these populations. The primary aim of the current study was to systematically review and provide a meta-analysis on the suitability of the verification phase for confirming 'true' [Formula: see text] in special and clinical groups. Secondary aims were to explore the applicability of the verification phase according to specific participant characteristics and investigate which test protocols and procedures minimise the differences between the highest [Formula: see text] values attained in the CPET and verification phase. METHODS: Electronic databases (PubMed, Web of Science, SPORTDiscus, Scopus, and EMBASE) were searched using specific search strategies and relevant data were extracted from primary studies. Studies meeting inclusion criteria were systematically reviewed. Meta-analysis techniques were applied to quantify weighted mean differences (standard deviations) in peak [Formula: see text] from a CPET and a verification phase within study groups using random-effects models. Subgroup analyses investigated the differences in [Formula: see text] according to individual characteristics and test protocols. The methodological quality of the included primary studies was assessed using a modified Downs and Black checklist to obtain a level of evidence. Participant-level [Formula: see text] data were analysed according to the threshold criteria reported by the studies or the inherent measurement error of the metabolic analysers and displayed as Bland-Altman plots. RESULTS: Forty-three studies were included in the systematic review, whilst 30 presented quantitative information for meta-analysis. Within the 30 studies, the highest mean [Formula: see text] values attained in the CPET and verification phase protocols were similar (mean difference = -0.00 [95% confidence intervals, CI = -0.03 to 0.03] L·min-1, p = 0.87; level of evidence, LoE: strong). The specific clinical groups with sufficient primary studies to be meta-analysed showed a similar [Formula: see text] between the CPET and verification phase (p > 0.05, LoE: limited to strong). Across all 30 studies, [Formula: see text] was not affected by differences in test protocols (p > 0.05; LoE: moderate to strong). Only 23 (53.5%) of the 43 reviewed studies reported how many participants achieved a lower, equal, or higher [Formula: see text] value in the verification phase versus the CPET or reported or supplied participant-level [Formula: see text] data for this information to be obtained. The percentage of participants that achieved a lower, equal, or higher [Formula: see text] value in the verification phase was highly variable across studies (e.g. the percentage that achieved a higher [Formula: see text] in the verification phase ranged from 0% to 88.9%). CONCLUSION: Group-level verification phase data appear useful for confirming a specific CPET protocol likely elicited [Formula: see text], or a reproducible [Formula: see text], for a given special or clinical group. Participant-level data might be useful for confirming whether specific participants have likely elicited [Formula: see text], or a reproducible [Formula: see text], however, more research reporting participant-level data is required before evidence-based guidelines can be given. TRIAL REGISTRATION: PROSPERO (CRD42021247658) https://www.crd.york.ac.uk/prospero.

Evaluating the contribution of the Glittre-ADL test in adults with cystic fibrosis.

BACKGROUND AND OBJECTIVES: Cardiopulmonary and skeletal muscle impairment and poor physical activity are potential contributors to reduced functional capacity in cystic fibrosis (CF). The Glittre-ADL test (TGlittre) has great potential for clinical use in adult CF adults, as it meets the need for a comprehensive assessment of physical function using tasks similar to activities of daily living. This study aimed to evaluate the performance of TGlittre in CF adults compared to the 6-min walk test (6MWT) and, secondarily, to quantify the associations of their results with pulmonary function, muscle strength, and health-related quality of life (HRQoL). METHODS: This cross-sectional study evaluated 34 CF adults and compared them with 34 subjects from a control group. The participants underwent the following assessments: functional capacity using TGlittre and 6MWT; spirometry; respiratory muscle strength; handgrip strength (HGS); and HRQoL using the Cystic Fibrosis Questionnaire-Revised (CFQ-R). RESULTS: While CF patients showed a longer time to perform TGlittre compared to controls (134 (119-150) versus 107 (95-126) % of the predicted time p = 0.0002), no difference between these groups was observed in the 6MWT. When the second TGlittre was compared to the first TGlittre, there was a significant decrease in total time for both CF patients (p < 0.0001) and controls (p = 0.0001). TGlittre time correlated with 6MWT distance (6MWD) (rs = -0.641, p < 0.0001), HGS (rs = -0.364, p = 0.034), peripheral oxygen saturation at the end of the test (rs = -0.463, p = 0.006) and the "digestive symptoms" domain of CFQ-R (rs = 0.376, p = 0.028). TGlittre time was shorter in patients who engaged in regular physical activity (3.10 (2.49-3.39) min versus 3.28 (2.95-3.53) min, p = 0.016). CONCLUSIONS: TGlittre is more effective than the 6MWT in detecting limitations during exercise. There is an important learning effect of TGlittre in adult CF patients. TGlittre time was correlated with 6MWD, HGS, oxygen saturation level, and the patient's level of physical activity.

Predischarge oxygen uptake efficiency slope has short and long-term value in the prognosis of patients after acute myocardial infarction.

BACKGROUND: Patients who survive an acute myocardial infarction (AMI) have a higher risk of having a major cardiovascular event (MACE). Cardiopulmonary exercise testing (CPET) could develop prognostic stratification and prescribing exercise prescription. Patients after AMI frequently terminate CPET early with submaximal testing results. We aimed to look at the characteristics of patients' predischarge CPET variables after AMI intervention and find potential CPET variables with prognostic value. METHODS: Between July 2012 and August 2017, we recruited patients who survived first AMI after primary percutaneous coronary intervention and received predischarge CPET retrospectively in a tertiary medical center of Taiwan. Patients were followed-up on a MACE or administrative censoring occurred (up to 5 years). To identify significant predictors of a MACE, a Cox regression model was used. RESULTS: One hundred thirteen patients (103 men and 10 women) were studied, with an average age of 58.32 ± 12.49. MACE over 3 months, 2-years, and 5-years was 17.70%, 53.10%, and 62.83%, respectively. The oxygen uptake efficiency slope during the whole during of CPET (OUES 100) divided by body surface area (OUES 100/BSA) was found to be a significant event predictor for MACE at 3-month, 2- and 5-years. Cox regression analysis revealed that those with OUES 100/BSA <0.722 ( p = 0.004), OUES 100/BSA <0.859 ( p = 0.002), and OUES 100/BSA <0.829 ( p = 0.002) had a 7.14-fold, 3.47-fold, and 2.72-fold increased risk of 3-month, 2-year, and 5-year MACE, respectively. CONCLUSION: It is critical to identify a submaximal predictor during CPET for patients who survive AMI. Our findings suggested that OUES could be a significant prognostic indicator in patients after first AMI in both the short and long term.

Integrative Assessment of Cardiopulmonary Fitness Using Cardiopulmonary Exercise Test With Supine Bicycle Echocardiography in Patients Presenting Dyspnea.

BACKGROUND: Cardiopulmonary exercise test (CPET) with supine bicycle echocardiography (SBE) enables comprehensive physiologic assessment during exercise. We characterized cardiopulmonary fitness by integrating CPET-SBE parameters and evaluated its prognostic value in patients presenting with dyspnea. METHODS AND RESULTS: We retrospectively reviewed 473 consecutive patients who underwent CPET-SBE for dyspnea evaluation. A dimensionality reduction process was applied, transforming 24 clinical and CPET-SBE parameters into a 2-dimensional feature map, followed by patient clustering based on the data distribution. Clinical and exercise features were compared among the clusters in addition to the 5-year risk of clinical outcome (a composite of cardiovascular death and heart failure hospitalization). Maximum exercise effort (R >1) was achieved in 95% of cases. Through dimensionality reduction, 3 patient clusters were derived: Group 1 (n=157), 2 (n=104), and 3 (n=212). Median age and female proportion increased from Group 1 to 2, and 3, although resting echocardiography parameters showed no significant abnormalities among the groups. There was a worsening trend in the exercise response from Group 1 to 2 and 3, including left ventricular diastolic function, oxygen consumption, and ventilatory efficiency. During follow-up (median 6.0 [1.6-10.4] years), clinical outcome increased from Group 1 to 2 and 3 (5-year rate 3.7% versus 7.0% versus 13.0%, respectively; log-rank P=0.02), with higher risk in Group 2 (hazard ratio, 1.94 [95% CI, 0.52-7.22]) and Group 3 (3.92 [1.34-11.42]) compared with Group 1. CONCLUSIONS: Comprehensive evaluation using CPET-SBE can reveal distinct characteristics of cardiopulmonary fitness in patients presenting with dyspnea, potentially enhancing outcome prediction.

Reliability and criterion-related validity of the Cooper test in pre-adolescents and adolescents: A systematic review and meta-analysis.

The Cooper test (CT) is used to assess cardiorespiratory fitness (CRF) in pre-adolescents and adolescents, although it was originally developed to assess healthy adults. The aim of this study is to examine the available scientific evidence on the reliability and criterion validity of CT when administered to pre-adolescents and adolescents. Systematic searches were performed in three electronic databases (MEDLINE/PubMed, SPORTDiscuss and Scopus). To examine reliability and validity, four separate meta-analyses were implemented, finding high heterogeneity in studies with low methodological quality. There was a paucity of research regarding absolute reliability, while studies attempting to develop or cross-validate VO2max/VO2peak equations were almost non-existent. Information on the psychometric properties of CT in pre-adolescents under 12 years of age is scarce. The findings of this review cast doubt on the usefulness of CT both in identifying CRF and in determining the impact of strategies developed to improve CRF among pre-adolescents and adolescents.

The combination of high-frequency QRS and ST-segment alterations during exercise stress tests enhanced the diagnostic efficacy for coronary artery disease.

BACKGROUND: High-frequency QRS (HF-QRS) manifests as a novel adjunct electrocardiographic marker with potential utility in coronary artery disease (CAD) detection. HYPOTHESIS: We hypothesize that HF-QRS analysis may be superior to conventional ST-segment analysis in detecting CAD, and the combination of these two analyses in the exercise stress test may enhance the diagnostic efficacy for CAD. METHODS: The study incorporated a sample of 157 patients (mean age 62 ± $\pm $ 9 years) referred for nonemergent angiography. Before angiography, patients underwent exercise stress testing utilizing an upright bicycle. High-resolution electrocardiogram (ECG) data were collected during the exercise test, facilitating both HF-QRS and conventional ST-segment analyses. The diagnostic efficacy of HF-QRS and ST-segment analysis were compared, utilizing angiographic outcomes as the gold standard. The study design integrated HF-QRS analysis and ST-segment analysis via sequential and concurrent testing protocols. RESULTS: In terms of CAD detection, HF-QRS analysis displayed superior sensitivity compared to conventional ST-segment analysis (63% vs. 37%, p = .002). The serial test significantly increased specificity from 79% to 97% (p = .002) compared to ST-deviation analysis alone. It showed a markedly low sensitivity of 26%. The parallel test significantly increased sensitivity from 37% to 77% (p < .001), while retaining a moderate level of specificity of 51%. The quantity of ECG leads exhibiting a positive HF-QRS response demonstrated a correlation with the severity of CAD (p < .001). CONCLUSIONS: HF-QRS analysis exhibited superior sensitivity in detecting angiographically confirmed CAD relative to conventional ST-segment analysis. Moreover, the combination of HF-QRS and ST-segment alterations during exercise stress test enhanced the diagnostic efficacy for CAD.

[Possibilities of Predicting Peak Oxygen Consumption in Patients With Chronic Heart Failure According to the 6­Minute Walk Test].

AIM: To determine the correlation between the results of the 6-minute walk test (6MWT) and peak oxygen consumption (VO2peak) for populations of patients with chronic heart failure with pronounced clinical and demographic differences; to study a possibility of indirect measurement of VO2peak based on the results of 6MWT using the formulas available from the literature. MATERIAL AND METHODS: Two databases were analyzed: 50 patients included in the AEROFIT study (group A), and 31 patients from the Almazov National Medical Research Center (group B). The inclusion criteria were the availability of data from the cardiopulmonary stress test and the 6MWT. The possibility of predicting VO2peak was calculated based on the results of 6MWT using the formulas reported in the literature (L. P. Cahalin et al., 1996; R. M. Ross et al., 2010; R. A. Adedoyin et al., 2010). The predictive accuracy of the models was assessed using the coefficient of determination (R2). The relationship between functional and clinical-demographic indicators was assessed using the Pearson or Spearman correlation analysis. RESULTS: The study groups differed significantly in all parameters, except for the proportion of men and the mean VO2peak. Group B patients were 20 years younger than group A patients, had a lower left ventricular ejection fraction (24.06±7.75 and 41.52±10.48 %, respectively; p<0.001), and covered a 130 m shorter distance in the 6MWT. Despite the absence of a significant difference in VO2peak between groups A and B (13.6 and 13.1 ml / kg / min, respectively; p=0.6581), 61 % of group B patients and 20% of group A belonged to Weber functional class IV. In group A, the 6MWT distance correlated closely with VO2peak (R=0.78; p<0.01) and weakly with age (R=0.4) and body mass index (R=0.3). In group B, the 6MWT distance correlated only with VO2peak (R=0.77; p<0.01). For group A, the R.M. Ross et al. model demonstrated high accuracy in determining the mean VO2peak value with a 0.06% prediction error normalized to measured VO2peak. For group B, none of the models showed satisfactory predictive accuracy. The Ross and Cahalin models showed the best coefficients of determination for groups A and B: Group A, Ross et al. (R2=0.58) and Cahalin et al. (R2=0.59); Group B, Ross et al. (R2=0.59) and Cahalin et al. (R2=0.6). CONCLUSION: In two groups of patients with a statistically insignificant difference in the mean values of VO2peak, the mean values of 6MWT distance were significantly different, although these indicators correlated closely. The VO2peak prediction models showed satisfactory accuracy for estimation of mean VO2, but poor accuracy for estimation of individual values. A better predictive accuracy is determined by similar clinical and demographic characteristics between the training and testing populations, and likely also by models based on larger, more diversified populations.

Procedures and measurement properties of the 6-min step test: A systematic review with clinical recommendations.

OBJECTIVE: To provide information regarding the procedures, safety, tolerability, and measurement properties of the 6-min step test. DATA SOURCES: MEDLINE, EMBASE, CINAHL, and SPORTDiscus (from inception until January 2024). REVIEW METHODS: Studies that examined adults with acute or chronic diseases, and outcomes related to procedures, safety, tolerability, or measurement properties of the 6-min step test were included. Outcome data were summarized and combined in meta-analyses. The quality of included studies was assessed by the Consensus-based Standards for the selection of health Measurement Instruments checklist, and the quality of evidence was determined according to the Grading of Recommendations Assessment, Development, and Evaluation system. RESULTS: Fourteen studies, involving 847 participants, were included. All studies performed the 6-min step test in 6 min; however, some studies varied the step height and the use of upper limb support. The test appears to be safe and well tolerated by individuals. Moderate- to high-quality evidence demonstrated appropriate results for test-retest reliability (4 studies; Intraclass correlation coefficient 0.96; 95% CI 0.91-0.98; n = 125), criterion validity (4 studies; r = 0.53; 95% CI 0.30-0.71; n = 307), and construct validity (4 studies; r = 0.63; 95% CI 0.52-0.73; n = 233). CONCLUSION: This review provides recommendations for applying the 6-min step test in clinical and research settings. No adverse events were reported, and the test appears to be well tolerated. Adequate results were found for test-retest reliability, criterion validity, and construct validity. REVIEW REGISTRATION: PROSPERO (CRD42022347744).

Validity of submaximal aerobic capacity and strength tests in firefighters.

BACKGROUND: Typically, the fitness of UK firefighters is assessed via submaximal estimate methods due to the low demands on time, money, expertise and equipment. However, the firefighter-specific validity of such testing in relation to maximum aerobic capacity (V˙O2max) and particularly muscular strength is not well established. AIMS: To examine the validity of submaximal methods to estimate V˙O2max and maximal strength in operational firefighters. METHODS: Twenty-two full-time operational firefighters (3 female) completed same-day submaximal (Chester Step Test; CST) and maximal (treadmill) assessments of V˙O2max, with a sub-sample of 10 firefighters (1 female) also completing submaximal and maximal back-squat (i.e. one repetition maximum; 1RM) assessments. All participants then completed the Firefighter Simulation Test (FFST) within 2-4 days. RESULTS: CST underestimated actual V˙O2max by 1.4 ml·kg-1·min-1 (~3%), although V˙O2max values were positively correlated (r = 0.61, P < 0.01) and not significantly different. Estimated V˙O2max values negatively correlated with FFST performance (r = -0.42). Predicted 1RM underestimated actual 1RM by ~2%, although these values were significantly correlated (r = 0.99, P < 0.001) and did not significantly differ. The strongest predictive model of FFST performance included age, body mass index, and direct maximal measures of 1RM and V˙O2max. CONCLUSIONS: Submaximal back-squat testing offers good validity in estimating maximum firefighter strength without exposure to the fatigue associated with maximal methods. The CST provides a reasonably valid and cost-effective V˙O2max estimate which translates to firefighting task performance, although the error observed means it should be used cautiously when making operational decisions related to V˙O2max benchmarks.

Gait patterns during overground and virtual omnidirectional treadmill walking.

BACKGROUND: Omnidirectional treadmills (ODTs) offer a promising solution to the virtual reality (VR) locomotion problem, which describes the mismatch between visual and somatosensory information and contributes to VR sickness. However, little is known about how walking on ODTs impacts the biomechanics of gait. This project aimed to compare overground and ODT walking and turning in healthy young adults. METHODS: Fifteen young adults completed forward walk, 180° turn, and 360° turn tasks under three conditions: (1) overground, (2) on the Infinadeck ODT in a virtual environment without a handrail, and (3) on the ODT with a handrail. Kinematic data for all walking trials were gathered using 3D optical motion capture. RESULTS: Overall, gait speed was slower during ODT walking than overground. When controlling for gait speed, ODT walking resulted in shorter steps and greater variability in step length. There were no significant differences in other spatiotemporal metrics between ODT and overground walking. Turning on the ODT required more steps and slower rotational speeds than overground turns. The addition of the stability handrail to the ODT resulted in decreased gait variability relative to the ODT gait without the handrail. CONCLUSION: Walking on an ODT resembles natural gait patterns apart from slower gait speed and shorter step length. Slower walking and shorter step length are likely due to the novelty of physically navigating a virtual environment which may result in a more conservative approach to gait. Future work will evaluate how older adults and those with neurological disease respond to ODT walking.

A Preliminary Investigation about the Influence of WIMU PROTM Location on Heart Rate Accuracy: A Comparative Study in Cycle Ergometer.

Technological development has boosted the use of multi-sensor devices to monitor athletes' performance, but the location and connectivity between devices have been shown to affect data reliability. This preliminary study aimed to determine whether the placement of a multi-sensor device (WIMU PROTM) could affect the heart rate signal reception (GARMINTM chest strap) and, therefore, data accuracy. Thirty-two physical education students (20 men and 12 women) performed 20 min of exercise in a cycle ergometer based on the warm-up of the Function Threshold Power 20 test in laboratory conditions, carrying two WIMU PROTM devices (Back: inter-scapula; Bicycle: bicycle's handlebar-20 cm from the chest) and two GARMINTM chest straps. A one-dimensional statistical parametric mapping test found full agreement between the two situations (inter-scapula vs. bicycle's handlebar). Excellent intra-class correlation values were obtained during the warm-up (ICC = 0.99, [1.00-1.00], p < 0.001), the time trial test (ICC = 0.99, [1.00-1.00], p < 0.001) and the cool-down (ICC = 0.99, [1.00-1.00], p < 0.001). The Bland-Altman plots confirmed the total agreement with a bias value of 0.00 ± 0.1 bpm. The interscapular back placement of the WIMU PROTM device does not affect heart rate measurement accuracy with a GARMINTM chest strap during cycling exercise in laboratory conditions.