Category Archives: Abstracts

Accelerometer Metrics: Healthy Adult Reference Values, Associations with Cardiorespiratory Fitness, and Clinical Implications

Med Sci Sports Exercise 2024 Feb 1;56(2):170-180.

Purpose: Accelerometer-assessed physical activity (PA) can be summarized using cut-point-free or population-specific cut-point-based outcomes. We aimed to 1) examine the interrelationship between cut-point-free (intensity gradient (IG) and average acceleration (AvAcc)) and cut-point-based accelerometer metrics, 2) compare the association between cardiorespiratory fitness (CRF) and cut-point-free metrics to that with cut-point-based metrics in healthy adults aged 20 to 89 yr and patients with heart failure, and 3) provide age-, sex-, and CRF-related reference values for healthy adults.

Methods: In the COmPLETE study, 463 healthy adults and 67 patients with heart failure wore GENEActiv accelerometers on their nondominant wrist and underwent cardiopulmonary exercise testing. Cut-point-free (IG: distribution of intensity of activity across the day; AvAcc: proxy of volume of activity) and traditional (moderate-to-vigorous and vigorous activity) metrics were generated. The “interpretablePA” R-package was developed to translate findings into clinical practice.

Results: IG and AvAcc yield complementary information on PA with both IG ( P = 0.009) and AvAcc ( P < 0.001) independently associated with CRF in healthy individuals (adjusted R2 = 73.9%). Only IG was independently associated with CRF in patients with heart failure ( P = 0.043, adjusted R2 = 38.4%). The best cut-point-free and cut-point-based model had similar predictive value for CRF in both cohorts. We produced age- and sex-specific reference values and percentile curves for IG, AvAcc, moderate-to-vigorous PA, and vigorous PA for healthy adults.

Conclusions: IG and AvAcc are strongly associated with CRF and thus indirectly with the risk of noncommunicable diseases and mortality, in healthy adults and patients with heart failure. However, unlike cut-point-based metrics, IG and AvAcc are comparable across populations. Our reference values provide a healthy age- and sex-specific comparison that may enhance the translation and utility of cut-point-free metrics in clinical practice.

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A verification phase adds little value to the determination of maximum oxygen uptake in well-trained adults

Eur J Appl Physiol 2024 Jan 18

Purpose: The objective was to investigate if performing a sub-peak or supra-peak verification phase following a ramp test provides additional value for determining ‘true’ maximum oxygen uptake ([Formula: see text]O2).

Methods: 17 and 14 well-trained males and females, respectively, performed two ramp tests each followed by a verification phase. While the ramp tests were identical, the verification phase differed in power output, wherein the power output was either 95% or 105% of the peak power output from the ramp test. The recovery phase before the verification phase lasted until capillary blood lactate concentration was ≤ 4 mmol·L-1. If a [Formula: see text]O2 plateau occurred during ramp test, the following verification phase was considered to provide no added value. If no [Formula: see text]O2 plateau occurred and the highest [Formula: see text]O2 ([Formula: see text]O2peak) during verification phase was < 97%, between 97 and 103%, or > 103% of [Formula: see text]O2peak achieved during the ramp test, no value, potential value, and certain value were attributed to the verification phase, respectively.

Results: Mean (standard deviation) [Formula: see text]O2peak during both ramp tests was 64.5 (6.0) mL·kg-1·min-1 for males and 54.8 (6.2) mL·kg-1·min-1 for females. For the 95% verification phase, 20 tests showed either a [Formula: see text]O2 plateau during ramp test or a verification [Formula: see text]O2peak < 97%, indicating no value, 11 showed potential value, and 0 certain value. For the 105% verification phase, the values were 26, 5, and 0 tests, respectively.

Conclusion: In well-trained adults, a sub-peak verification phase might add little value in determining ‘true’ maximum [Formula: see text]O2, while a supra-peak verification phase adds no value.

Autonomic dysfunction and exercise intolerance in post-COVID-19 – An as yet underestimated organ system?

Schwendinger, F; University Basel | Departement for Sport, Exercise and Health (DSBG), Switzerland
Looser, V; Gerber, M; Schmidt-Trucksass;

Int J Clin Health Psychol. 2024 Jan-Mar; 24(1):100429

Individuals recovering from COVID-19 often present with persistent symptoms, particularly exercise intolerance and low cardiorespiratory fitness. Put simply, the Wasserman gear system describes the interdependence of heart, lungs, and musculature as determinants of cardiorespiratory fitness. Based on this system, recent findings indicate a contribution of peripheral, cardiovascular, and lung diffusion limitations to persistent symptoms of exercise intolerance and low cardiorespiratory fitness. The autonomic nervous system as an organ system involved in the pathophysiology of exercise intolerance and low cardiorespiratory fitness, has received only little attention as of yet. Hence, our article discusses contribution of the autonomic nervous system through four potential pathways, namely alterations in (1) cerebral hemodynamics, (2) afferent and efferent signaling, (3) central hypersensitivity, and (4) appraisal and engagement in physical activity. These pathways are summarized in a psycho-pathophysiological model. Consequently, this article encourages a shift in perspective by examining the state of the pulmonary and cardiovascular system, the periphery, and auxiliary, the autonomic nervous system as potential underlying mechanisms for exercise intolerance and low cardiorespiratory fitness in patients with post-COVID-19.

 

Preoperative aerobic fitness and perioperative outcomes in patients undergoing cystectomy before and after implementation of a national lockdown.

Tetlow N; Department of Anaesthesia and Peri-operative Medicine, University College London Hospitals
Dewar A; Arina P; Tan M; Sridhar AN; Kelly JD; Arulkumaran N; Stephens RCM; London, UK.; Martin DS; Moonesinghe SR; Whittle J;

BJA open [BJA Open] 2024 Jan 17; Vol. 9, pp. 100255.
Date of Electronic Publication: 2024 Jan 17 (Print Publication: 2024).

Background: Lower fitness is a predictor of adverse outcomes after radical cystectomy. Lockdown measures during the COVID-19 pandemic affected daily physical activity. We hypothesised that lockdown during the pandemic was associated with a reduction in preoperative aerobic fitness and an increase in postoperative complications in patients undergoing radical cystectomy.
Methods: We reviewed routine preoperative cardiopulmonary exercise testing (CPET) data collected prior to the pandemic (September 2018 to March 2020) and after lockdown (March 2020 to July 2021) in patients undergoing radical cystectomy. Differences in CPET variables, Postoperative Morbidity Survey (POMS) data, and length of hospital stay were compared.
Results: We identified 267 patients (85 pre-lockdown and 83 during lockdown) who underwent CPET and radical cystectomy. Patients undergoing radical cystectomy throughout lockdown had lower ventilatory anaerobic threshold (9.0 [7.9-10.9] vs 10.3 [9.1-12.3] ml kg -1 min -1 ; P =0.0002), peak oxygen uptake (15.5 [12.9-19.1] vs 17.5 [14.4-21.0] ml kg -1 min -1 ; P =0.015), and higher ventilatory equivalents for carbon dioxide (34.7 [31.4-38.5] vs 33.4 [30.5-36.5]; P =0.030) compared with pre-lockdown. Changes were more pronounced in males and those aged >65 yr. Patients undergoing radical cystectomy throughout lockdown had a higher proportion of day 5 POMS-defined morbidity (89% vs 75%, odds ratio [OR] 2.698, 95% confidence interval [CI] 1.143-6.653; P =0.019), specifically related to pulmonary complications (30% vs 13%, OR 2.900, 95% CI 1.368-6.194; P =0.007) and pain (27% vs 9%, OR 3.471, 95% CI 1.427-7.960; P =0.004), compared with pre-lockdown on univariate analysis.
Conclusions: Lockdown measures in response to the COVID-19 pandemic were associated with a reduction in fitness and an increase in postoperative morbidity among patients undergoing radical cystectomy.

Reduced exercise capacity for muscle mass in adolescents living with obesity.

Colapelle J; Experimental Medicine, McGill University Experimental Medicine, Montréal, Quebec, Canada.
St-Pierre J; Erdstein J; Lands LC;

Pediatric pulmonology [Pediatr Pulmonol] 2024 Jan 31.
Date of Electronic Publication: 2024 Jan 31.

Background: Adolescents living with obesity (AlwO) can have limited exercise capacity. Exercise capacity can be predicted by a 2-factor model comprising lung function and leg muscle function, but no study has looked at cycling leg muscle function and its contribution to cycling exercise capacity in AlwO.
Methods: Twenty-two nonobese adolescents and 22 AlwO (BMI > 95 percentile) were studied. Anthropometry, body composition (dual-energy X-ray absorptiometry), spirometry, 30-s isokinetic work capacity, and maximal exercise (cycle ergometry) were measured.
Results: AlwO had greater total body mass, lean body mass, and lean leg mass (LLM). Lung function trended higher in AlwO. Leg 30-s work did not differ in absolute terms or per allometrically scaled LLM. Peak oxygen consumption did not differ between the groups in absolute terms or as percent predicted values (79.59 ± 14.6 vs. 82.3 ± 11.2% predicted control versus ALwO) but was lower in AlwO when expressed per kg body mass, kg lean body mass, scaled lean body mass, and LLM. Peak oxygen consumption related to both lung function and 30-s work, with no observed group effect. 30-s leg work related to the scaled LLM, with a small group effect. There was some correlation between leg work and time spent in moderate to vigorous physical activity in AlwO (r s  = 0.39, p = .07).
Conclusion: AlwO have larger LLM and preserved exercise capacity, when expressed as percentage of predicted, but not per allometrically scaled LLM. Increasing time spent in moderate to vigorous activity may benefit AlwO.

Effect of ubiquinol on electrophysiology during high-altitude acclimatization and de-acclimatization: A substudy of the Shigatse CARdiorespiratory fitness (SCARF) randomized clinical trial.

Liu Z; The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, PR China.
Yang J; Yang B; Sun M; Ye X; Yu S; Tan H; Hu M; Lv H; Wu B; Gao X; Huang L

International journal of cardiology [Int J Cardiol] 2024 Feb 01, pp. 131817.
Date of Electronic Publication: 2024 Feb 01.

Background: High-altitude exposure changes the electrical conduction of the heart. However, reports on electrocardiogram (ECG) characteristics and potent prophylactic agents during high-altitude acclimatization and de-acclimatization are inadequate. This study aimed to investigate the effects of ubiquinol on electrophysiology after high-altitude hypoxia and reoxygenation.
Methods: The study was a prospective, randomized, double-blind, placebo-controlled trial. Forty-one participants were randomly divided into two groups receiving ubiquinol 200 mg daily or placebo orally 14 days before flying to high altitude (3900 m) until the end of the study. Cardiopulmonary exercise testing was performed at baseline (300 m), on the third day after reaching high altitude, and on the seventh day after returning to baseline.
Results: Acute high-altitude exposure prolonged resting ventricular repolarization, represented by increased corrected QT interval (455.9 ± 23.4 vs. 427.1 ± 19.1 ms, P < 0.001) and corrected T peak -T end interval (155.5 ± 27.4 vs. 125.3 ± 21.1 ms, P < 0.001), which recovered after returning to low altitude. Ubiquinol supplementation shortened the hypoxia-induced extended T peak -T end interval (-7.7 ms, [95% confidence interval (CI), -13.8 to -1.6], P = 0.014), T peak -T end /QT interval (-0.014 [95% CI, -0.027 to -0.002], P = 0.028), and reserved maximal heart rate (11.9 bpm [95% CI, 3.2 to 20.6], P = 0.013) during exercise at high altitude. Furthermore, the decreased resting amplitude of the ST-segment in the V3 lead was correlated with decreased peak oxygen pulse (R = 0.713, P < 0.001) and maximum oxygen consumption (R = 0.595, P < 0.001).
Conclusions: Our results illustrated the electrophysiology changes during high-altitude acclimatization and de-acclimatization. Similarly, ubiquinol supplementation shortened the prolonged T peak -T end interval and reserved maximal heart rate during exercise at high altitude.

Use of exercise tests in screening for pulmonary arterial hypertension in systemic sclerosis: A systematic literature review.

Madigan S; School of Medicine, The University of Adelaide,  Australia.;
Proudman S; Schembri D; Davies H; Adams R;

Journal of scleroderma and related disorders [J Scleroderma Relat Disord] 2024 Feb; Vol. 9 (1), pp. 50-58.
Date of Electronic Publication: 2023 Oct 02.

Background and Objective: Patients with systemic sclerosis (SSc) and pulmonary arterial hypertension (PAH) have a poor prognosis, accounting for 30% of all SSc-related deaths. Guidelines recommend annual screening for PAH regardless of symptoms, as early treatment improves outcomes. Current protocols include combinations of clinical features, biomarkers, pulmonary function tests, and echocardiography. None include exercise testing, although early-stage PAH may only be evident during exercise. This systematic review assessed the performance of exercise tests in predicting the presence of PAH in patients with SSc, where PAH was confirmed through right heart catheterisation (RHC).
Methods: Comprehensive literature searches were performed using MEDLINE, EMBASE, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trails, CINAHL, Scopus and Web of Science from inception to May 2023. Articles were screened for eligibility by two independent reviewers. Eligibility criteria included the use of a non-invasive exercise test to screen adult patients to detect PAH in a population without a previous diagnosis of PAH, with diagnosis confirmed by RHC.
Results: Eight studies met the inclusion criteria, describing at least one of three different non-invasive exercise tests: cardiopulmonary exercise test, six-minute walk test and stress Doppler echocardiography. All studies found that exercise tests had some ability to predict the presence of PAH, with sensitivity between 50% and 100% and specificity from 73% to 91%.
Conclusion: Exercise tests are infrequently used for screening for PAH in SSc but can predict the presence of PAH. More data are required to establish which tests are most effective.

 

Pre-participation screenings frequently miss occult cardiovascular conditions in apparently healthy male middle-aged first-time marathon runners.

Laily I; Wiggers TGH; van Steijn N; Bijsterveld N; Bakermans AJ; Froeling M; van den Berg-Faay S; de Haan FH; de Bruin-Bon RHACM; Boekholdt SM; Planken RN; Verhagen E;  Jorstad HT;

Cardiology [Cardiology] 2024 Feb 07.
Date of Electronic Publication: 2024 Feb 07.

Introduction: The optimal pre-participation screening strategy to identify athletes at risk for exercise-induced cardiovascular events is unknown. We therefore aimed to compare the American College of Sports Medicine (ACSM) and European Society of Cardiology (ESC) pre-participation screening strategies against extensive cardiovascular evaluations in identifying high-risk individuals among 35-50-year-old apparently healthy men.
Methods: We applied ACSM and ESC pre-participation screenings to 25 men participating in a study on first-time marathon running. We compared screening outcomes against medical history, physical examination, electrocardiography, blood tests, echocardiography, cardiopulmonary exercise testing, and magnetic resonance imaging.
Results: ACSM screening classified all participants as ‘medical clearance not necessary’. ESC screening classified two participants as ‘high-risk’. Extensive cardiovascular evaluations revealed ≥1 minor abnormality and/or cardiovascular condition in 17 participants, including three subjects with mitral regurgitation and one with a small atrial septal defect. Eleven participants had dyslipidaemia, six had hypertension, and two had premature atherosclerosis. Ultimately, three (12%) subjects had a serious cardiovascular condition warranting sports restrictions: aortic aneurysm, hypertrophic cardiomyopathy (HCM), and myocardial fibrosis post-myocarditis. Of these three participants, only one had been identified as ‘high-risk’ by the ESC screening (for dyslipidaemia, not HCM) and none by the ACSM screening.
Conclusion: Numerous occult cardiovascular conditions are missed when applying current ACSM/ESC screening strategies to apparently healthy middle-aged men engaging in their first high-intensity endurance sports event.

Taking a walk on the heart failure side: comparison of metabolic variables during walking and maximal exertion.

Mapelli M; Centro Cardiologico Monzino IRCCS, Milan, Italy.;
Salvioni E; Bonomi A; Paneroni M; Raimondo R; Gugliandolo P; Mattavelli I; Bidoglio J; Mirza KK; La Rovere MT; Gustafsson F; Agostoni P;

ESC heart failure [ESC Heart Fail] 2024 Jan 29.
Date of Electronic Publication: 2024 Jan 29.

Aims: Although cardiopulmonary exercise testing (CPET) is the gold standard to assess exercise capacity, simpler tests (i.e., 6-min walk test, 6MWT) are also commonly used. The aim of this study was to evaluate the relationship between cardiorespiratory parameters during CPET and 6MWT in a large, multicentre, heterogeneous population.
Methods: We included athletes, healthy subjects, and heart failure (HF) patients of different severity, including left ventricular assist device (LVAD) carriers, who underwent both CPET and 6MWT with oxygen consumption measurement.
Results: We enrolled 186 subjects (16 athletes, 40 healthy, 115 non-LVAD HF patients, and 15 LVAD carriers). CPET-peakV̇O 2 was 41.0 [35.0-45.8], 26.2 [23.1-31.0], 12.8 [11.1-15.3], and 15.2 [13.6-15.6] ml/Kg/min in athletes, healthy, HF patients, and LVAD carriers, respectively (P < 0.001). During 6MWT they used 63.5 [56.3-76.8], 72.0 [57.8-81.0], 95.5 [80.3-109], and 95.0 [92.0-99.0] % of their peakV̇O 2 , respectively. None of the athletes, 1 healthy (2.5%), 30 HF patients (26.1%), and 1 LVAD carrier (6.7%), reached a 6MWT-V̇O 2 higher than their CPET-peakV̇O 2 . Both 6MWT-V̇O 2 and walked distance were significantly associated with CPET-peakV̇O 2 in the whole population (R 2  = 0.637 and R 2  = 0.533, P ≤ 0.001) but not in the sub-groups. This was confirmed after adjustment for groups.
Conclusions: The 6MWT can be a maximal effort especially in most severe HF patients and suggest that, in absence of prognostic studies related to 6MWT metabolic values, CPET should remain the first method of choice in the functional assessment of patients with HF as well as in sport medicine.

Cardiopulmonary Exercise Testing Interpretation in Athletes: What the Cardiologist Should Know.

Husaini M; Department of Medicine,  Washington University School of Medicine,
Emery MS;

Cardiac electrophysiology clinics [Card Electrophysiol Clin] 2024 Mar; Vol. 16 (1), pp. 71-80.

The noninvasive assessment of oxygen consumption, carbon dioxide production, and ventilation during a cardiopulmonary exercise test (CPET) provides insight into the cardiovascular, pulmonary, and metabolic system’s ability to respond to exercise. Exercise physiology has been shown to be distinct for competitive athletes and highly active persons (CAHAPs), thus creating more nuanced interpretations of CPET parameters. CPET in CAHAP is an important test that can be used for both diagnosis (provoking symptoms during a truly maximal test) and performance.