A Novel Method for Identifying Frailty and Quantifying Muscle Strength Using the Six-Minute Walking Test.

The six-minute walking test (6MWT) is an essential test for evaluating exercise tolerance in many respiratory and cardiovascular diseases. Frailty and sarcopenia can cause rapid aging of the cardiovascular system in elderly people. Early detection and evaluation of frailty and sarcopenia are crucial for determining the treatment method. We aimed to develop a wearable measuring system for the 6MWT and propose a method for identifying frailty and quantifying walking muscle strength (WMS). In this study, 60 elderly participants were asked to wear accelerometers behind their left and right ankles during the 6MWT. The gait data were collected by a computer or smartphone. We proposed a method for analyzing walking performance using the stride length (SL) and step cadence (SC) instead of gait speed directly. Four regions (Range I-IV) were divided by cutoff values of SC = 2.0 [step/s] and SL = 0.6 [m/step] for a quick view of the frail state. There were 62.5% of frail individuals distributed in Range III and 72.4% of non-frail individuals in Range I. A concept of a WMS score was proposed for estimating WMS quantitatively. We found that 62.5% of frail individuals were scored as WMS1 and 41.4% of the non-frail elderly as WMS4. The average walking distances corresponding to WMS1-4 were 207 m, 370 m, 432 m, and 462 m, respectively. The WMS score may be a useful tool for quantitatively estimating sarcopenia or frailty due to reduced cardiopulmonary function.

Physical Functioning, Physical Activity, and Variability in Gait Performance during the Six-Minute Walk Test.

Instrumenting the six-minute walk test (6MWT) adds information about gait quality and insight into fall risk. Being physically active and preserving multi-directional stepping abilities are also important for fall risk reduction. This analysis investigated the relationship of gait quality during the 6MWT with physical functioning and physical activity. Twenty-one veterans (62.2 ± 6.4 years) completed the four square step test (FSST) multi-directional stepping assessment, a gait speed assessment, health questionnaires, and the accelerometer-instrumented 6MWT. An activity monitor worn at home captured free-living physical activity. Gait measures were not significantly different between minutes of the 6MWT. However, participants with greater increases in stride time (ρ = -0.594, p < 0.01) and stance time (ρ = -0.679, p < 0.01) during the 6MWT reported lower physical functioning. Neither physical activity nor sedentary time were related to 6MWT gait quality. Participants exploring a larger range in stride time variability (ρ = 0.614, p < 0.01) and stance time variability (ρ = 0.498, p < 0.05) during the 6MWT required more time to complete the FSST. Participants needing at least 15 s to complete the FSST meaningfully differed from those completing the FSST more quickly on all gait measures studied. Instrumenting the 6MWT helps detect ranges of gait performance and provides insight into functional limitations missed with uninstrumented administration. Established FSST cut points identify aging adults with poorer gait quality.

The Long-Term Benefit of Exercise With and Without Manual Therapy for Mild Chronic Obstructive Pulmonary Disease: A Randomized Controlled Trial.

PURPOSE: Chronic obstructive pulmonary disease (COPD) is characterized by decreasing exercise capacity and deteriorating quality of life (QoL). Recent evidence indicates that combining exercise with manual therapy (MT) delivers greater improvements in exercise capacity than exercise alone in moderate COPD. The aim of this study was to investigate whether this combination delivers similar results in mild COPD. METHODS: A total of 71 participants aged 50-65 yr with mild COPD were randomly allocated to two groups: exercise only (Ex) or MT plus exercise (MT + Ex). Both groups received 16 wk of exercise with the MT + Ex group also receiving 8 MT sessions. Lung function (forced vital capacity [FVC] and forced expiratory volume in the 1 st sec [FEV 1 ]), exercise capacity (6-min walk test [6MWT]), and QoL (St George's Respiratory Questionnaire [SGRQ] and Hospital Anxiety and Depression Scale [HADS]) were measured at baseline, 4, 8, 16, 24, 32, and 48 wk. RESULTS: Although there was no difference in the mean effect over time between groups for lung function (FEV 1 , P = .97; FVC, P = .98), exercise capacity (6MWT, P = .98), and QoL (SGRQ, P = .41; HADS anxiety, P = .52; and HADS depression, P = .06), there were clinically meaningful improvements at 48 wk for 6MWT (30 m; 95% CI, 10-51 m; P < .001), SGRQ (6.3 units; 95% CI, 2.5-10.0; P < .001), and HADS anxiety (1.5 units; 95% CI, 0.3-2.8 units; P = .006) across the entire cohort. CONCLUSIONS: While adding MT to Ex did not produce any additional benefits, exercise alone did deliver sustained modest improvements in exercise capacity and QoL in mild COPD.

Six-minute walk test as clinical end point in cardiomyopathy clinical trials, including ATTR-CM: a systematic literature review.

Aim: The six-minute walk test (6MWT) is a common measure of functional capacity in patients with heart failure (HF). Primary clinical study end points in cardiomyopathy (CM) trials, including transthyretin-mediated amyloidosis with CM (ATTR-CM), are often limited to hospitalization and mortality. Objective: To investigate the relationship between the 6MWT and hospitalization or mortality in CM, including ATTR-CM. Method: A PRISMA-guided systematic literature review was conducted using search terms for CM, 6MWT, hospitalization and mortality. Results: Forty-one studies were identified that reported 6MWT data and hospitalization or mortality data for patients with CM. The data suggest that a greater 6MWT distance is associated with a reduced risk of hospitalization or mortality in CM. Conclusion: The 6MWT is an accepted alternative end point in CM trials, including ATTR-CM.

Gait speed in knee osteoarthritis: A simple 10-meter walk test predicts the distance covered in the 6-minute walk test.

BACKGROUND: The 6-Minute Walk Test (6MWT) is a common performance-measure in Knee Osteoarthritis (KOA), but the pain and functional impairment characterizing the condition may interfere its adequate performance. OBJECTIVES: The shorter 10-m Walk Test (10mWT) could predict the distance performed on the 6MWT, therefore decreasing the burden on patients, enhancing efficiency, and reducing space- and time-constraints in clinical settings. DESIGN: A cross sectional study was conducted. METHODS: The scores from the 6MWT and the shorter 10mWT of 58 ambulatory subjects with KOA were compared. Correlation, and a univariate regression analysis to explore the predictive ability of the 10mWT, were calculated. RESULTS: Correlation was excellent (r = 0.913, p-value<0.001), and the predictive equation based on the 10mWT scores (R2 = 0.834, p-value<0.001) estimates the distance walked in the 6MWT with a relative error of 7.62%. CONCLUSIONS: The 10mWT may be an excellent assessment-tool to predict the distance walked in the 6MWT, due to its low strain on patients and as a means of improving efficiency and reducing time-constraints.

Evaluating current assessment techniques of cardiorespiratory fitness.

INTRODUCTION: Considerable and convincing global data from cohorts across the health spectrum (i.e. apparently healthy to known disease) indicate that cardiorespiratory fitness (CRF) is a major predictor of overall and cardiovascular disease (CVD)-survival, seemingly with greater prognostic resolution compared to other traditional CVD risk factors. Therefore, the assessment of CRF in research and clinical settings is of major importance. AREAS COVERED: In this manuscript, we review the technology of measuring CRF assessed by the 'gold standard,' cardiopulmonary exercise testing (CPET), as well as with various other methods (e.g. estimated metabolic equivalents, 6-minute walk tests, shuttle tests, and non-exercise equations that estimate CRF), all of which provide significant prognostic information for CVD- and all-cause survival. The literature through May 2024 has been cited. EXPERT OPINION: The promotion of physical activity in efforts to improve levels of CRF is needed throughout the world to improve lifespan and, more importantly, healthspan. The routine assessment of CRF should be considered a vital sign that is routinely assessed in clinical practice.

The heart rate response to the 6-min walk test in atrial fibrillation patients with or without beta-blockers: Referring to patients with sinus rhythm.

BACKGROUND: The aim was to evaluate the effect of beta-blockers (BB) on the response of heart rate (HR) to 6-min walk test (6MWT) in atrial fibrillation (AF) and whether the AF patients treated with BB have a similar HR response to 6MWT as the AF and sinus rhythm (SR) patients without BB treatment at the same resting HR level. METHODS: The before-after study involving 74 AF patients was to evaluate the effect of BB treatment (pre-BB and with BB). The comparison study included 74 BB-treated AF patients (with BB), 74 matched AF patients without BB (no BB), and 74 SR patients. The percentage increase amplitude of HR (HR-PIA) in 6MWT was calculated: [(the exercise HR - the resting HR)/(the resting HR)] × 100%. RESULTS: The before-after study showed that BB treatment decreased the resting and mean exercise HR (98.6 ± 15.2 vs. 85.5 ± 11.2 bpm and 121.3 ± 17.3 vs. 109.0 ± 16.7 bpm) during 6MWT. The comparison study demonstrated that against the SR, the AF with BB and no BB groups have higher mean exercise HR-PIA (28.2 ± 17.1% and 22.0 ± 9.6%, vs. 6.9 ± 3.7%) when their resting HR is similar. Moreover, the mean exercise HR-PIA was also significantly higher in the with BB group than in the no BB group. CONCLUSION: In AF patients with relatively higher resting HR, BB treatment could decrease the resting and exercise HR during 6MWT. However, BB treatment could not effectively attenuate the exercise HR rise as compared with AF without BB treatment, even with similar resting HR levels.

Longitudinal strain correlates with 6-minute walk distance whereas ejection fraction and diastolic parameters do not.

BACKGROUND: Impaired functional capacity is a common symptom in patients with heart failure. Standard measures of left ventricular (LV) function, such as ejection fraction (EF) and LV diastolic parameters, do not correlate with measures of functional capacity. The aim of this study is to determine if measures of global and regional LV strain better correlate with 6-minute walk distance than does EF or measures of LV diastolic function. METHODS: 120 patients referred to a cardiology clinic for evaluation of known or suspected heart failure were approached for enrollment. Of those 120 patients, 58 had an echocardiogram within 3 months of enrollment with images adequate for regional and global strain assessment, had no contra-indication to exercise testing, and had no previously documented non-cardiac explanation for dyspnea on exertion. In those 58 patients, 6-minute walk distance was measured, LV EF was determined with Simpson's biplane method, and global and regional longitudinal strain were measured with TomTec Image Arena 4.5.1 software. RESULTS: LV EF had no correlation with 6-minute walk distance (r = 0.22, p = 0.09) even when controlling for age, gender, and BMI (p = 0.07). No measures of LV diastolic function (including E velocity, Deceleration Time, e' annular velocities, or E/e') had a correlation with 6-minute walk distance. Multiple measures of global and regional LV longitudinal systolic function had a correlation with 6-minute walk distance. Longitudinal strain of the basal LV segments had the strongest correlation with 6-minute walk distance (r= -0.36, p = 0.005), and correlation persisted after controlling for age, gender, BMI, and systolic blood pressure (p = 0.004). CONCLUSIONS: Longitudinal strain correlates with a measure of functional capacity, but LVEF and traditional measures of LV diastolic dysfunction do not. Measures of longitudinal strain, especially in basal LV segments, will likely be an important marker of clinically relevant LV function.

Assessing Functional Capacity in Directly and Remotely Monitored Home-Based Settings in Individuals With Chronic Respiratory Diseases: Protocol for a Multinational Validation Study.

BACKGROUND: Pulmonary rehabilitation is widely recommended to improve functional status and as secondary and tertiary prevention in individuals with chronic pulmonary diseases. Unfortunately, access to timely and appropriate rehabilitation remains limited. To help close this inaccessibility gap, telerehabilitation has been proposed. However, exercise testing is necessary for effective and safe exercise prescription. Current gold-standard tests, such as maximal cardiopulmonary exercise testing (CPET) and the 6-minute walk test (6MWT), are poorly adapted to home-based or telerehabilitation settings. This was an obstacle to the continuity of services during the COVID-19 pandemic. It is essential to validate tests adapted to these new realities, such as the 6-minute stepper test (6MST). This test, strongly inspired by 6MWT, consists of taking as many steps as possible on a "stepper" for 6 minutes. OBJECTIVE: This study aims to evaluate the metrological qualities of 6MST by (1) establishing concurrent validity and agreement between the 6MST and CPET, as well as with the 6MWT; (2) determining test-retest reliability in a home-based setting with direct and remote (videoconferencing) monitoring; and (3) documenting adverse events and participant perspectives when performing the 6MST in home-based settings. METHODS: Three centers (Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec in Québec, Groupement des Hôpitaux de l'Institut Catholique de Lille in France, and FormAction Santé in France) will be involved in this multinational project, which is divided into 2 studies. For study 1 (objective 1), 30 participants (Québec, n=15; France, n=15) will be recruited. Two laboratory visits will be performed to assess anthropometric data, pulmonary function, and the 3 exercise tolerance tests (CPET, 6MWT, and 6MST). Concurrent validity (paired sample t tests and Pearson correlations) and agreement (Bland-Altman plots with 95% agreement limits) will be evaluated. For study 2 (objectives 2 and 3), 52 participants (Québec, n=26; France, n=26) will be recruited. Following a familiarization trial (trial 1), the 6MST will be conducted on 2 separate occasions (trials 2 and 3), once under direct supervision and once under remote supervision, in a randomized order. Paired sample t test, Bland-Altman plots, and intraclass correlations will be used to compare trials 2 and 3. A semistructured interview will be conducted after the third trial to collect participants' perspectives. RESULTS: Ethical approval was received for this project (October 12, 2023, in Québec and September 25, 2023, in France) and the first participant was recruited in February 2024. CONCLUSIONS: This study innovates by validating a new clinical test necessary for the development and implementation of new models of rehabilitation adapted to home and telerehabilitation contexts. This study also aligns with the United Nations Sustainable Development Goals by contributing to augmenting health care service delivery (goal 3) and reducing health care access inequalities (goal 11). TRIAL REGISTRATION: ClinicalTrials.gov NCT06447831; https://clinicaltrials.gov/study/NCT06447831. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/57404.

Prognostic Value of a 6-Minute Walk Test in Patients With Transthyretin Cardiac Amyloidosis.

BACKGROUND: The 6-minute walk test (6MWT) represents a comprehensive functional assessment that is commonly used in patients with heart failure; however, data are lacking in patients with transthyretin cardiac amyloidosis (ATTR-CA). OBJECTIVES: This study aimed to assess the prognostic importance of the 6MWT in patients with ATTR-CA. METHODS: A retrospective analysis of patients diagnosed with ATTR-CA at the National Amyloidosis Centre who underwent a baseline 6MWT between 2011 and 2023 identified 2,141 patients, of whom 1,118 had follow-up at 1 year. RESULTS: The median baseline 6MWT distance was 347 m (Q1-Q3: 250-428 m) and analysis by quartiles demonstrated an increased death rate with each distance reduction (deaths per 100 person-years: 6.3 vs 9.2 vs 13.6 vs 19.0; log-rank P < 0.001). A 6MWT distance of <350 m was associated with a 2.2-fold higher risk of mortality (HR: 2.15; 95% CI: 1.85-2.50; P < 0.001), with a similar increased risk across National Amyloidosis Centre disease stages (P for interaction = 0.761) and genotypes (P for interaction = 0.172). An absolute (reduction of >35 m) and relative worsening (reduction of >5%) of 6MWT at 1 year was associated with an increased risk of mortality (HR: 1.80; 95% CI: 1.51-2.15; P < 0.001 and HR: 1.89; 95% CI: 1.59-2.24; P < 0.001, respectively), which was similar across the aforementioned subgroups. When combined with established measures of disease progression (N-terminal pro-B-type natriuretic peptide progression and outpatient diuretic intensification), each incremental increase in progression markers was associated with an increased death rate (deaths per 100 person-years: 7.6 vs 13.9 vs 22.4 vs 32.9; log-rank P < 0.001). CONCLUSIONS: The baseline 6MWT distance can refine risk stratification beyond traditional prognosticators. A worsening 6MWT distance can stratify disease progression and, when combined with established markers, identifies patients at the highest risk of mortality.

Responsiveness and minimal clinically important difference of the 6-minute walk distance in patients undergoing colorectal cancer surgery.

PURPOSE: This study aimed to clarify the responsiveness and minimal clinically important difference (MCID) of the 6-minute walk distance (6MWD) from before and 1 week after surgery in patients with colorectal cancer (CRC). METHODS: This retrospective cohort study enrolled 97 patients with primary CRC scheduled for surgery. An anchor-based approach estimated the MCID of the 6MWD, with postoperative physical recovery and EuroQol 5-dimension 5L questionnaire assessments serving as anchors. Effect size (ES) and standardized response mean (SRM) of the 6MWD were calculated to evaluate responsiveness, and the receiver operating characteristic (ROC) curve was used to estimate the MCID of the 6MWD. RESULTS: Of the 97 patients, 72 were included in the analysis. The absolute value of ES and SRM of the 6MWD were 0.69 and 0.91, respectively. The ROC curve indicated that the optimal cut-off values for estimating the MCID of the 6MWD were -60 m (area under the curve [AUC] = 0.753 [95% CI: 0.640-0.866]) and -75 m (AUC = 0.870 [95% CI: 0.779-0.961]) at each anchor. CONCLUSION: From before to 1 week after surgery, the responsiveness of the 6MWD was favorable, and the MCID of the 6MWD was -75 to -60 m in patients with CRC.

Measuring Physical Functioning Using Wearable Sensors in Parkinson Disease and Chronic Obstructive Pulmonary Disease (the Accuracy of Digital Assessment of Performance Trial Study): Protocol for a Prospective Observational Study.

BACKGROUND: Physical capacity and physical activity are important aspects of physical functioning and quality of life in people with a chronic disease such as Parkinson disease (PD) or chronic obstructive pulmonary disease (COPD). Both physical capacity and physical activity are currently measured in the clinic using standardized questionnaires and tests, such as the 6-minute walk test (6MWT) and the Timed Up and Go test (TUG). However, relying only on in-clinic tests is suboptimal since they offer limited information on how a person functions in daily life and how functioning fluctuates throughout the day. Wearable sensor technology may offer a solution that enables us to better understand true physical functioning in daily life. OBJECTIVE: We aim to study whether device-assisted versions of 6MWT and TUG, such that the tests can be performed independently at home using a smartwatch, is a valid and reliable way to measure the performance compared to a supervised, in-clinic test. METHODS: This is a decentralized, prospective, observational study including 100 people with PD and 100 with COPD. The inclusion criteria are broad: age ≥18 years, able to walk independently, and no co-occurrence of PD and COPD. Participants are followed for 15 weeks with 4 in-clinic visits, once every 5 weeks. Outcomes include several walking tests, cognitive tests, and disease-specific questionnaires accompanied by data collection using wearable devices (the Verily Study Watch and Modus StepWatch). Additionally, during the last 10 weeks of this study, participants will follow an aerobic exercise training program aiming to increase physical capacity, creating the opportunity to study the responsiveness of the remote 6MWT. RESULTS: In total, 89 people with PD and 65 people with COPD were included in this study. Data analysis will start in April 2024. CONCLUSIONS: The results of this study will provide information on the measurement properties of the device-assisted 6MWT and TUG in the clinic and at home. When reliable and valid, this can contribute to a better understanding of a person's physical capacity in real life, which makes it possible to personalize treatment options. TRIAL REGISTRATION: ClinicalTrials.gov NCT05756075; https://clinicaltrials.gov/study/NCT05756075. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/55452.

Dual Tasking Affects the Outcomes of Instrumented Timed up and Go, Sit-to-Stand, Balance, and 10-Meter Walk Tests in Stroke Survivors.

Stroke can impair mobility, with deficits more pronounced while simultaneously performing multiple activities. In this study, common clinical tests were instrumented with wearable motion sensors to study motor-cognitive interference effects in stroke survivors (SS). A total of 21 SS and 20 healthy controls performed the Timed Up and Go (TUG), Sit-to-Stand (STS), balance, and 10-Meter Walk (10MWT) tests under single and dual-task (counting backward) conditions. Calculated measures included total time and gait measures for TUG, STS, and 10MWT. Balance tests for both open and closed eyes conditions were assessed using sway, measured using the linear acceleration of the thorax, pelvis, and thighs. SS exhibited poorer performance with slower TUG (16.15 s vs. 13.34 s, single-task p < 0.001), greater sway in the eyes open balance test (0.1 m/s2 vs. 0.08 m/s2, p = 0.035), and slower 10MWT (12.94 s vs. 10.98 s p = 0.01) compared to the controls. Dual tasking increased the TUG time (~14%, p < 0.001), balance thorax sway (~64%, p < 0.001), and 10MWT time (~17%, p < 0.001) in the SS group. Interaction effects were minimal, suggesting similar dual-task costs. The findings demonstrate exaggerated mobility deficits in SS during dual-task clinical testing. Dual-task assessments may be more effective in revealing impairments. Integrating cognitive challenges into evaluation can optimize the identification of fall risks and personalize interventions targeting identified cognitive-motor limitations post stroke.

Clinical utility of the Borg dyspnoea score in 6-minute walk tests in interstitial lung disease: A systematic review.

BACKGROUND: Exertional dyspnoea, a cardinal symptom in interstitial lung disease (ILD), can be objectively measured during a 6-min walk test (6MWT) using the Borg Dyspnoea Score (BDS). However, the clinical utility of this measurement is unclear. The purpose of this systematic review was to determine the association between 6MWT BDS and prognosis (mortality and lung transplantation), other 6MWT variables and measures of pulmonary function. METHODS: MEDLINE, EMBASE, Cochrane and SCOPUS databases were used to identify studies reporting an association between post-6MWT BDS and the relevant outcomes in adults with ILD. Language was limited to English. Study quality was assessed using the Quality in Prognosis Study risk of bias tool. A narrative synthesis for each outcome was performed. RESULTS: Ten full-text studies (n = 518) were included. Four studies had high overall risk of bias. Two studies (n = 127) reported prognosis and both found that higher 6MWT BDS was associated with increased all-cause mortality. However, the certainty of evidence was very low due to study design and likely publication bias. Higher post-6MWT BDS may be associated with shorter, or no effect on 6MWD; and lower pulmonary function. There was insufficient evidence that BDS correlated with 6MWT oxygen saturation. CONCLUSIONS: Post-6MWT BDS has a potential role as a predictor of all-cause mortality in ILD, 6MWD and lower pulmonary function. Larger studies designed to confirm these relationships and assess the independent association between the 6MWT BDS and clinical outcomes are required.

In-Person Versus Remote 6-Minute Walk and Incremental Shuttle Walk Distances in Advanced Lung Disease.

BACKGROUND: Field-based walk tests conducted remotely may provide an alternative method to a facility-based assessment of exercise capacity for people with advanced lung disease. This prospective study evaluated the level of agreement in the distance walked between a 6-min walk test (6MWT) and an incremental shuttle walk test performed by using standard in-person procedures and test variations and settings. METHODS: Adults with advanced lung disease underwent 4 study visits: (i) one in-person standard 6MWT (30-m corridor) and one in-person treadmill 6MWT, (ii) a remote 6MWT in a home setting (10-m corridor), (iii) 2 in-person standard incremental shuttle walk tests (10-m corridor), and (iv) a remote incremental shuttle walk test in a home setting (10-m corridor). A medical-grade oximeter measured heart rate and oxygen saturation before, during, and for 2 min after the tests. RESULTS: Twenty-eight participants were included (23 men [82%]; 64 (57-67) y old; 19 with interstitial lung disease [68%] and 9 with COPD [32%]; and 26 used supplemental oxygen (93%) [exertional [Formula: see text] of 0.46 ± 0.1]). There was no agreement between the tests. Greater walking distances were achieved with standard testing procedures: in-person 6MWT versus treadmill 6MWT (355 ± 68 vs 296 ± 97; P = .001; n = 28), in-person 6MWT versus remote 6MWT (349 ± 68 vs 293 ± 84; P = .001; n = 24), and in-person incremental shuttle walk test versus remote incremental shuttle walk test (216 ± 62 vs 195 ± 63; P = .03; n = 22). CONCLUSIONS: Differences in the distance walked may have resulted from different track lengths, widths, and walking surfaces. This should be considered in test interpretation if tests are repeated under different conditions.

Exercise capacity prior to major cancer surgery: A cross-sectional observational study of the validity of the 6-minute walk and 30-second sit-to-stand tests.

INTRODUCTION: Cardiopulmonary exercise testing (CPET) is the gold standard for measuring exercise capacity, however, it is resource intensive and has limited availability. This study aimed to determine: 1) the association between the 6-min walk test (6MWT) and the 30-s sit-to-stand test (30STS) with CPET peak oxygen uptake (VO2peak) and anaerobic threshold (AT) and 2) 6MWT and 30STS cut points associated with a higher risk of postoperative complications. METHODS: A cross-sectional study, retrospectively analyzing data collected from a tertiary cancer center over a 23-month period. Measures included CPET VO2peak and AT, 6MWT and 30STS test. Correlations were used to characterize relationships between variables. Receiver operating characteristic curve analyses determined 6MWT and 30STS cut points that aligned with CPET variable cut points. RESULTS: Note that, 156 participants were included. The 6MWT and 30STS displayed moderate correlations with VO2peak, rho = 0.65, p = 0.01 and rho = 0.52, p < 0.005 respectively. Fair correlations were observed between AT and 6MWT (rho = 0.36, p = 0.01) and 30STS (rho = 0.41, p < 0.005). The optimal cut points to identify VO2peak < 15 mL/kg/min were 493.5 m on the 6MWT and 12.5 stands on the 30STS test and for AT < 11 mL/kg/min were 506.5 m on the 6MWT and 12.5 stands on the 30STS test. CONCLUSION: Both the 6MWT and 30STS test could be used as alternative tools for measuring exercise capacity preoperatively in the cancer setting where CPET is not available. A range of 6MWT and 30STS cut points, according to sensitivity and specificity levels, may be used to evaluate risk of postoperative outcomes.

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.

Concurrent Validity and Reliability of Video-Based Approach to Assess Physical Function in Adults With Knee Osteoarthritis.

OBJECTIVES: The aim of this study was to determine the concurrent validity and reliability of the Osteoarthritis Research Society International recommended performance-based tests delivered by video-based in adults with knee osteoarthritis. METHODS: Thirty-two participants (aged 40-70 years; 15 men) undertook assessments of 4 performance-based tests via both video-based (real-time and recorded) and face-to-face approaches, on the same day. Outcome measures were performance-based test and the number of technical issues encountered. The performance-based tests included the 40-Meter Fast-Paced Walk Test (velocity, m/s), the 30-Second Chair Stand Test (number of repetitions), the Stair Climb Test (time, seconds), and the Timed "Up & Go" Test (time, seconds). The Bland-Altman limit of agreement measures, standard error of measurement (SEM), coefficient of variation (CV), minimal detectable changes, and bias (mean difference) were employed to analyze the concurrent validity between video-based and face-to-face approaches of the performance-based tests. Reliability was measured using intraclass correlation coefficients, CV, and SEM. RESULTS: A high degree of concurrent validity for the Timed "Up & Go" Test (bias = -0.22), the 30-Second Chair Stand Test (bias = -0.22), the Stair Climb Test (bias = -0.31), and the 40-Meter Fast-Paced Walk Test (bias = -0.06) was found. SEM and CV values were within the acceptable level for concurrent validity. There was a high degree of reliability demonstrated for all tests analyzed. Intraclass correlation coefficient measures ranged from 0.95 to 1.00 for intrarater reliability, and from 0.95 to 0.99 for interrater reliability. CONCLUSIONS: Video-based assessment of physical performance tests is a valid and reliable tool for measuring physical function among adults with knee osteoarthritis via Microsoft Teams (Microsoft Corp, Redmond, WA, USA). IMPACT: Video-based assessment is a promising public health tool to measure physical function in adults with knee osteoarthritis.

Hemodynamic, ventilatory and gas exchange responses to exercise using a cycle ergometer and the incremental shuttle walk test in pregnant women.

BACKGROUND: Cardiovascular disease, including hypertension, in pregnant women is a leading cause of morbidity and mortality globally. The development of reference intervals for cardiovascular responses using exercising testing to measure oxygen utilisation (V̇O2) with cardiopulmonary exercise testing (CPET), and distances walked using the incremental shuttle walk test (ISWT), may be promising methods to assess and stratify pregnant women regarding their risk of adverse pregnancy outcomes, to encourage exercise during pregnancy, and to improve exercise prescriptions during pregnancy. We aimed to determine the reference intervals for V̇O2 at rest, anaerobic threshold (AT), and submaximal exercise using CPET, and the reference interval for the ISWT, to develop a correlation equitation that predicts submaximal V̇O2 from the distance walked in the ISWT, and to explore the relationship between hemoglobin (Hb) and ferritin concentration and V̇O2 at AT in women in second trimester. METHODS: After prospective IRB approval (HREC 15/23) and clinical trials registration (ANZCTR ACTRN12615000964516), and informed written consent, we conducted CPET and the ISWT according to international guidelines in a university associated tertiary referral obstetric and adult medicine hospital, in healthy pregnant women in second trimester (14 to 27 gestational weeks). Hemoglobin and ferritin concentrations were recorded from pathology results in the participants' medical records at the time of exercise testing. Adverse events were recorded. RESULTS: About 90 participants undertook CPET, 28 of which also completed the ISWT. The mean ± SD age and body mass index (BMI) were 32 ± 3.2 years, and 25 ± 2.7 kg/m2. Median (IQR) gestation was 23 (22-24) weeks. One in 4 women were 24 weeks or greater gestation. The reference intervals for V̇O2 at rest, AT, and submaximal exercise were 2.9 to 5.3, 8.1 to 20.7, and 14.1 to 30.5 mL/kg/min respectively. The reference interval for the ISWT was 218 to 1058 meters. The correlation equation to predict submaximal V̇O2 from the distance walked in the ISWT was submaximal V̇O2 (mL/kg/min) = 0.012*distance walked in ISWT (m) + 14.7 (95%CI slope 0.005-0.070, Pearson r = 0.5426 95%CI 0.2126-0.7615, P = .0029). Hemoglobin concentration was positively correlated with V̇O2 at AT (AT V̇O2 (mL/kg/min) = 0.08*Hb (g/L) + 4.9 (95%CI slope 0.0791-0.143, Pearson r = 0.2538 95%CI 0.049-0.438, P = .016). There was no linear association between ferritin and submaximal V̇O2 (Pearson r = 0.431 P = .697). There were no maternal or fetal complications. CONCLUSIONS: CPET and ISWT are safe and feasible in women in second trimester including those at or beyond 24 weeks gestation. We have established the reference interval for V̇O2 at rest, AT, and submaximal exercise by CPET, the reference interval for the distance walked for the ISWT, and a correlation equation to predict submaximal V̇O2 for use in clinical practice and research. Hemoglobin rather than ferritin is likely correlated with exercise capacity in pregnancy suggesting vigilance to correct lower hemoglobin levels may positively impact maternal health. CLINICAL TRIALS REGISTRY: The study was prospectively registered with the Australian and New Zealand Clinical Date of registration - 15/9/2015; Date of initial participant enrolment - 4/11/2015; Clinical trial identification number; ACTRN12615000964516; URL of the registration site - https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=369216.

Effect of Adding a Program of Contextualized, Personalized, Remote Physical Activity Support to Conventional Cardiac Rehabilitation.

PURPOSE: The objective of this investigation was to conduct a randomized controlled trial to evaluate whether KiActiv Heart alongside usual care (UC) promotes positive physical activity (PA) change versus UC alone. METHODS: Patients in cardiac rehabilitation (n = 130) undertook an 8-wk intervention with follow-up at wk 8. Both groups attended UC and wore a PA monitor during the intervention. The intervention group accessed the digital service and received weekly one-to-one remote mentor sessions. The primary outcome was change in PA to achieve the Association of Certified Physiotherapists in Cardiac Rehabilitation (ACPICR) recommendations. The secondary outcome was cardiorespiratory fitness (CRF) change, measured using incremental shuttle walk test (ISWT). RESULTS: The probability of meeting ACPICR "Daily Activity" recommendation was statistically significantly greater in the intervention group versus control at wk 8 ( P < .05). No statistically significant differences between groups were found for mean ISWT change (intervention 89 ± 116 m; control 44 ± 124 m). CONCLUSION: Participation in KiActiv Heart alongside UC was associated with statistically significant improvement in probability of meeting ACPICR recommendation and non-statistically significant but potentially clinically important increases in CRF versus UC alone. This builds on existing evidence for effectiveness.