Predicting VO2peak from Submaximal- and Peak Exercise Models: The HUNT 3 Fitness Study, Norway

Maximal cardiopulmonary exercise testing in laryngectomised patients using different heat and moisture exchangers - feasibility and exercise responses

OBJECTIVE

After laryngectomy, the breathing resistance of heat and moisture exchangers may limit exercise capacity. Breathing gas analysis during cardiopulmonary exercise testing is not possible using regular masks. This study tested the feasibility of cardiopulmonary exercise testing with a heat and moisture exchanger in situ, using an in-house designed connector. Additionally, we explored the effect of different heat and moisture exchanger resistances on exercise capacity in this group.

METHODS

Ten participants underwent two cardiopulmonary exercise tests using their daily life heat and moisture exchanger (0.3 hPa or 0.6 hPa) and one specifically developed for activity (0.15 hPa). Heat and moisture exchanger order was randomised and blinded.

RESULTS

All participants completed both tests. No (serious) adverse events occurred. Only four subjects reached a respiratory exchange ratio of more than 1.1 in at least one test. Maximum exercise levels using heat and moisture exchangers with different resistances did not differ.

CONCLUSION

Cardiopulmonary exercise testing in laryngectomees with a heat and moisture exchanger is feasible; however, the protocol does not seem appropriate to reach this group's maximal exercise capacity. Lowering heat and moisture exchanger resistance does not increase exercise capacity in this sample.

Comparative efficacy of different exercise methods to improve cardiopulmonary function in stroke patients: a network meta-analysis of randomized controlled trials

Background

Although some studies have shown that exercise has a good effect on improving the cardiopulmonary function of stroke patients, it still needs to be determined which exercise method does this more effectively. We, therefore, aimed to evaluate the effectiveness of different exercise methods in improving cardiovascular function in stroke patients through a network meta-analysis (NMA), providing a basis to select the best treatment plan for stroke patients.

Methods

We systematically searched CNKI, WanFang, VIP, CBM, PubMed, Embase, Web of Science, and The Cochrane Library databases from establishment to 30 April 2023. Randomized controlled trials (RCTS) on exercise improving cardiopulmonary function in stroke patients were included, and we screened the included articles and extracted the relevant data. RevMan (version 5.4) and Stata (version 17.0) were used for data analysis.

Results

We included 35 RCTs and a total of 2,008 subjects. Intervention measures included high-intensity interval training (HIIT), aerobic training (AT), resistance training (RT), combined aerobic and resistance exercise (CE), and conventional therapy (CT). In the network meta-analysis, the surface under the cumulative ranking area (SUCRA) ranking result indicated that HIIT improved peak oxygen uptake (VO2peak) and 6 mins walking distance (6MWD) optimally, with rankings of HIIT (100.0%) > CE (70.5%) > AT (50.2%) > RT (27.7%) > CT (1.6%), and HIIT (90.9%) > RT (60.6%) > AT (48.9%) > RT (48.1%) > CT (1.5%), respectively. The SUCRA ranking result showed that CE improved systolic blood pressure (SBP) and diastolic blood pressure (DBP) optimally, with rankings of CE (82.1%) > HIIT (49.8%) > AT (35.3%) > CT (32.8%), and CE (86.7%) > AT (45.0%) > HIIT (39.5%) > CT (28.8%), respectively.

Conclusion

We showed that exercise can effectively improve the cardiopulmonary function of stroke patients. HIIT was the most effective in improving VO2peak and 6MWD in stroke patients. CE was the most effective in improving SBP and DBP in stroke patients. However, due to the limitations of existing clinical studies and evidence, larger sample size, multi-center, and high-quality RCTs are needed to verify the above conclusions in the future.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier [CRD42023436773].

Comparative efficacy of nine exercise methods on the prognosis in chronic kidney disease patients with hemodialysis: a systematic review and network meta-analysis

BACKGROUND

Several kinds of physical activities have been applied to improve the prognosis of patients with hemodialysis (HD). However, the comparative efficacy of physical activities on the outcomes in HD patients is still unknown. This study explored the effectiveness and safety of all exercise types in HD patients.

METHODS

We searched randomized clinical trials from the PubMed, EMBASE, and Cochrane Library databases. Physical exercises interventions included resistance exercise (RE), aerobic exercise (AE), electrical muscle stimulation (EMS), range of motion (ROM), resistance exercise + aerobic exercise (RE + AE), stretching exercise (STE), respiratory muscle training (RMT), peripheral muscle training (PMT), walking exercise (WE), or usual care/sham exercise (UC/SE). Primary outcomes were six-minute walk test (6-mwt) and quality of life (QOL). Secondary outcomes were Kt/V, VO2max, hemoglobin (Hb), C-reactive protein (CRP), interleukin-6 (IL-6), and systolic and diastolic blood pressure (sbp and dbp). Frequentist network meta-analysis with multivariate random effects models provided mean with 95% confidence intervals (95%CI).

RESULTS

A total of 58 eligible studies were included. AE, RMT, and RE + AE significantly improved 6-mwt compared with UC/SE. SE was the worst intervention and reduced QOL much more than the UC/SE and other exercise types. AE and RE + AE were associated with higher VO2max, while ROM and RE + AE induced higher Hb levels. All physical activities did not elevate blood pressure, CRP and IL-6. Only ROM decreased sbp/dbp. CRP is significantly lower in RE.

CONCLUSION

Physical activities play a crucial role in the different outcomes of HD patients. They can be applied to specific area for their specific efficacy.

Adherence to a Web-based Exercise Programme: A Feasibility Study Among Patients with Hip or Knee Osteoarthritis

OBJECTIVES

To describe adherence to a 12-week web-based aerobic exercise programme, to compare characteristics between those who adhere or not, and to identify barriers for exercising in patients with hip or knee osteoarthritis.

DESIGN

Single-arm feasibility study.

SUBJECTS

Patients with hip or knee osteoarthritis in specialist healthcare, age 40-80 years, and not candidates for joint surgery.

METHODS

Adherence to a 12-week exercise programme was defined as having completed ≥ 2 exercise sessions a week for at least 8 weeks. Baseline differences between adherent and non-adherent groups in demographics, symptoms, disability, physical activity and fitness were assessed using Mann-Whitney U or χ2 tests. Reasons for not completing exercise sessions were reported in weekly diaries.  Results: A total of 29 patients (median age 64 years, 72% female) were included. Median baseline pain (numerical rating scale 0-10) was 5. Fifteen patients adhered to the exercise programme, 14 did not. Non-adherent patients were less active (p = 0.032) and had lower cardiorespiratory fitness (p = 0.031). The most frequently reported barrier to exercising was sickness. Less than 10% reported pain as a barrier.

CONCLUSION

Half of the patients with hip or knee osteoarthritis adhered to the digitally delivered exercise programme and the most frequently reported barrier for adherence was sickness, while less than 10% reported pain as a reason for not exercising.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04084834. The Regional Committee for Medical and Health Research Ethics South-East, 2018/2198.

Predicting Maximum Oxygen Uptake from Non-Exercise and Submaximal Exercise Tests in Paraplegic Men with Spinal Cord Injury

This study aimed to develop prediction equations for maximum oxygen uptake (VO₂max) based on non-exercise (anthropometric) and submaximal exercise (anthropometric and physiological) variables in paraplegic men with a spinal cord injury. All participants were tested on an arm ergometer using a maximal graded exercise test. Anthropometric variables such as age, height, weight, body fat, body mass index, body fat percentage, and arm muscle mass and physiological variables such as VO₂, VCO₂, and heart rate at 3 and 6 min of graded exercise tests were included in the multiple linear regression analysis. The prediction equations revealed the following. Regarding non-exercise variables, VO₂max was correlated with age and weight (equation R = 0.771, R² = 0.595, SEE= 3.187). Regarding submaximal variables, VO₂max was correlated with weight and VO₂ and VCO₂ at 6 min (equation R = 0.892, R² = 0.796, SEE = 2.309). In conclusion, our prediction equations can be used as a cardiopulmonary function evaluation tool to estimate VO₂max simply and conveniently using the anthropometric and physiological characteristics of paraplegic men with spinal cord injuries.

Descriptive Epidemiology of Cardiorespiratory Fitness in UK Adults: The Fenland Study

INTRODUCTION

Cardiorespiratory fitness (CRF) is rarely measured in population studies. Most studies of CRF do not examine differences by population subgroups or seasonal trends. We examined how estimated CRF levels vary by anthropometric, sociodemographic, and behavioral characteristics in a population-based cohort of UK adults (the Fenland Study).

METHODS

We used a validated submaximal exercise test to obtain CRF estimates (CRF estimated ) in 5976 women and 5316 men, residing in the East of England. CRF estimated was defined as estimated maximal oxygen consumption per kilogram total body mass (V̇O 2 max tbm ) and fat-free mass (V̇O 2 max ffm ). Descriptive statistics were computed across anthropometric and sociodemographic characteristics, and across the year. Progressive multivariable analyses were performed to examine associations with physical activity energy expenditure (PAEE) and body mass index (BMI).

RESULTS

Mean ± SD V̇O 2 max tbm was lower in women (35.2 ± 7.5 mL·min -1 ·kg -1 ) than men (41.7 ± 7.3 mL·min -1 ·kg -1 ) but V̇O 2 max ffm was similar (women: 59.2 ± 11.6 mL·min -1 ·kg -1 ; men: 62.0 ± 10.3 mL·min -1 ·kg -1 ). CRF estimated was inversely associated with age but not after adjustment for PAEE. People in more physically demanding jobs were fitter compared with those in sedentary jobs, but this association was attenuated in women and reversed in men after adjustment for total PAEE. Physical activity energy expenditure and BMI were positively associated with CRF estimated at all levels of adjustment when expressed relative to fat-free mass. CRF estimated was 4% higher in summer than in winter among women, but did not differ by season among men.

CONCLUSIONS

CRF estimated was inversely associated with age but less steeply than anticipated, suggesting older generations are comparatively fitter than younger generations. Physical activity energy expenditure and BMI were stronger determinants of the variance in CRF estimated than other characteristic including age. This emphasizes the importance of modifiable physical activity behaviors in public health interventions.

Comparative efficacy of exercise modalities for cardiopulmonary function in hemodialysis patients: A systematic review and network meta-analysis

Background

To provide reliable evidence to exercise rehabilitation therapists and clinicians, we compared and analyzed the effects of different exercise modalities on cardiopulmonary function in hemodialysis patients using Bayesian network meta-analysis.

Methods

PubMed, OVID, Web of Science, Cochrane Library, Embase, Scopus, CINAHL, SPORT Discus, SinoMed, CNKI, Wanfang, and VIP were searched from inception to July 20, 2022. We included randomized controlled trials comparing 12 exercise modalities to improve cardiorespiratory fitness in hemodialysis patients. All statistical analysis was performed using STATA and R.

Result

A total of 82 randomized controlled trials involving 4146 maintenance hemodialysis patients were included in this study. The pair-wise meta-analysis showed that all exercise modalities had a positive effect on all indicators of cardiorespiratory capacity. The network meta-analysis demonstrated that Blood flow restriction training (BFRT), Cycle exercise (CE), Inspiratory muscle training (IMT), Combined aerobic and resistance training (CT), and Aerobic training (AT) were significantly better than usual care for 6-min walkability; Medium intensity continuous training (MICT), CT, CE, and AT were considerably better than usual care for VO₂Peak; body and mind training (MBT) and CT significantly improved SBP compared to usual care; and only MBT was significantly better than usual care for DBP. Both the two-dimensional plot and the radar plot demonstrated that CT had the best combined-effect on each index of cardiorespiratory fitness. Subgroup and sensitivity analyses demonstrated the robustness of the results. The evidence was mainly "low" to "very low" for this network meta-analysis.

Conclusion

There is no one exercise that can achieve the best effect on all of the outcomes. The benefits of MBT in decreasing arterial blood pressure are unsurpassed by other exercise methods. The intervention effect of the CT is better and more stable. Electrical muscle stimulation training (MEST) can be employed in individuals who do not wish to exercise actively but may cause an increase in blood pressure. On the basis of the characteristics of different exercise types, guidelines developers, clinicians, and patients may employ them appropriately.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/#recordDetails.

Exploring the interplay between mechanisms of neuroplasticity and cardiovascular health in aging adults: A multiple linear regression analysis study

BACKGROUND

Neuroplasticity and cardiovascular health behavior are critically important factors for optimal brain health.

OBJECTIVE

To assess the association between the efficacy of the mechanisms of neuroplasticity and metrics of cardiovascular heath in sedentary aging adults.

METHODS

We included thirty sedentary individuals (age = 60.6 ± 3.8 y; 63 % female). All underwent assessments of neuroplasticity, measured by the change in amplitude of motor evoked potentials elicited by single-pulse Transcranial Magnetic Stimulation (TMS) at baseline and following intermittent Theta-Burst (iTBS) at regular intervals. Cardiovascular health measures were derived from the Incremental Shuttle Walking Test and included Heart Rate Recovery (HRR) at 1-min/2-min after test cessation. We also collected plasma levels of brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF), and c-reactive protein.

RESULTS

We revealed moderate but significant relationships between TMS-iTBS neuroplasticity, and the predictors of cardiovascular health (|r| = 0.38 to 0.53, p < .05). HRR1 was the best predictor of neuroplasticity (β = 0.019, p = .002). The best fit model (Likelihood ratio = 5.83, p = .016) of the association between neuroplasticity and HRR1 (β = 0.043, p = .002) was selected when controlling for demographics and health status. VEGF and BDNF plasma levels augmented the association between neuroplasticity and HRR1.

CONCLUSIONS

Our findings build on existing data demonstrating that TMS may provide insight into neuroplasticity and the role cardiovascular health have on its mechanisms. These implications serve as theoretical framework for future longitudinal and interventional studies aiming to improve cardiovascular and brain health. HRR1 is a potential prognostic measure of cardiovascular health and a surrogate marker of brain health in aging adults.

The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis

Background

Patient organisations may be an under-utilised resource in follow-up of patients requiring long-term exercise as part of their disease management. The purpose of this study was to explore the feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis (OA).

Methods

In this pre–post feasibility study, patients aged 40–80 years with hip and/or knee OA were recruited from Diakonhjemmet Hospital. The 12-week intervention was delivered through a patient organisation’s digital platform. Feasibility was evaluated by proportion of eligible patients enrolled, proportion of enrolled patients who provided valid accelerometer data at baseline, and proportion completing the cardiorespiratory exercise test according to protocol at baseline and completed follow-up assessments. Patient acceptability was evaluated for website usability, satisfaction with the initial exercise level and comprehensibility of the exercise program. Change in clinical outcomes were assessed for physical activity, cardiorespiratory fitness and patient-reported variables.

Results

In total, 49 eligible patients were identified and 35 were enrolled. Thirty (86%) of these attended baseline assessments and provided valid accelerometer data and 18 (51%) completed the maximal cardiorespiratory exercise test according to protocol. Twenty-two (63%) patients completed the follow-up questionnaire, and they rated the website usability as ‘acceptable’ [median 77.5 out of 100 (IQR 56.9, 85.6)], 19 (86%) reported that the initial exercise level was ‘just right’ and 18 (82%) that the exercise program was ‘very easy’ or ’quite easy’ to comprehend. Improvement in both moderate to vigorous physical activity (mean change 16.4 min/day; 95% CI 6.9 to 25.9) and cardiorespiratory fitness, VO_2peak (mean change 1.83 ml/kg/min; 95% CI 0.29 to 3.36) were found in a subgroup of 8 patients completing these tests. Across all patient-reported outcomes 24–52% of the patients had a meaningful improvement (n = 22).

Conclusion

A web-based exercise program delivered by a patient organisation was found to be feasible and acceptable in patients with hip and/or knee OA.

Trial registration

ClinicalTrials.gov, NCT04084834 (registered 10 September 2019). The Regional Committee for Medical and Health Research Ethics south-east, 2018/2198. URL: Prosjekt #632074 - Aktiv med web-basert støtte. - Cristin (registered 7 June 2019).

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-022-01110-3.

Maximal Aerobic Power Using the Modified Heck Protocol: Prediction Models

The purpose of this study was to develop prediction models based on an incremental treadmill test to volitional exhaustion utilizing the modified Heck protocol. A total of 598 professional and youth athletes participating in different sports were recruited for this study. Specifically, the study enrolled professional male soccer players (n=380), professional male futsal players (n=24), elite male basketball players (n=27), professional male soccer referees (n=50), elite female soccer players (n=19), youth male basketball players (13-14 yrs n=15, 15-17 yrs n=20) and youth male soccer players (15 yrs n=28, 16-17 yrs n=35). Anthropometric measurements included stature, body mass, and body fat. Furthermore, all participants performed incremental cardiopulmonary exercise testing on a treadmill using the modified Heck protocol. Through multiple regression analysis, a separate prediction model was developed for each of the athletic populations. Results demonstrated that a significant (p=0.001) proportion of the variation observed in VO₂max was explained by the variation in running time. The generated VO₂max regression equations would allow athletes and coaches to predict VO₂max in a relatively short time without the need for expensive and sophisticated equipment. To our knowledge, this is the first study that provides regression models for different athletic populations using the modified Heck protocol.

Immersive Virtual Reality Influences Physiologic Responses to Submaximal Exercise: A Randomized, Crossover Trial

Objectives: This cross-sectional, randomly assigned study aimed to assess the influence of immersive virtual reality (VR) on exercise tolerance expressed as the duration of a submaximal exercise test (ET) on a cycle ergometer. Methods: The study enrolled 70 healthy volunteers aged 22-25years. Each participant performed an ET with and without VR. Time- and frequency-domain heart rate variability (HRV) parameters were analyzed for the first 3min (T1), the last 3min (T2), and the time at which the shorter of the two tests terminated (Tiso). In the time domain, a SD of R-R intervals (SDNN) and a root mean square of successive R-R interval differences (RMSSD) in milliseconds were computed. The following spectral components were considered: low frequency (LF), high frequency (HF), total power (TP), and LF/HF ratio. The study was registered in ClinicalTrials.gov (NCT04197024). Results: Compared to standard ET, tests in immersive VR lasted significantly longer (694 vs. 591s, p<0.00001) and were associated with lower HR response across the range of corresponding exercise levels, averaging 5-8 beats/min. In the multiple regression analysis, the ET duration was positively determined by male sex, immersion in VR, and negatively determined by HRT1 and RMSSDT1. Conclusion: Exercising in VR is associated with lower HR which allowed subjects to exercise for a longer time before reaching target heart rate (HR). In addition, the increase in exercise duration was found to be related to an adjustment in autonomic nervous activity at a given work rate favoring parasympathetic predominance.

Estimation of maximal oxygen uptake from the 3,000 m run in adult men and women

The 3,000 m run is a frequently used field test for evaluating aerobic fitness. The test has previously been validated using smaller sample sizes and with focus restricted to the correlation between run performance and maximal oxygen uptake (V̇O_2max). The aim of the present study was to generate equations for converting 3,000 m performance into predicted V̇O_2max , and present corresponding validity statistics. In total 259 (30 female) military cadets and recruits (18-39 years) participated in the study. The subjects carried out a 3,000 m run and a direct treadmill V̇O_2max test. The Pearson r between V̇O_2max and average 3,000 m run speed were 0.74 and 0.79 in men and women, respectively. Two V̇O_2max prediction equations were generated: (1) Men: Ŷ = 17.5 + 2.57X and (2) Women: Ŷ = 14.6 + 2.48X (X = 3,000 m average run speed in km·h^-1). The equations produced a standard error of estimate of 3.3 and 2.6 mL·kg^-1·min^-1, and limits of agreement of 6.4 and 5.0 mL·kg^-1·min^-1 in men and women, respectively. The validity of the 3,000 m test is comparable to other indirect maximal running tests and is a time-effective alternative aerobic fitness test in healthy and motivated subjects.

Accuracy of Exercise-based Equations for Estimating Cardiorespiratory Fitness

Equations are often used to predict cardiorespiratory fitness (CRF) from submaximal or maximal exercise tests. However, no study has comprehensively compared these exercise-based equations with directly measured CRF using data from a single, large cohort.

PURPOSE

This study aimed to compare the accuracy of exercise-based prediction equations with directly measured CRF and evaluate their ability to classify an individual's CRF.

METHODS

The sample included 4871 tests from apparently healthy adults (38% female, age 44.4 ± 12.3 yr (mean ± SD)). Estimated CRF (eCRF) was determined from 2 nonexercise equations, 3 submaximal exercise equations, and 10 maximal exercise equations; all eCRF calculations were then compared with directly measured CRF, determined from a cardiopulmonary exercise test. Analysis included Pearson product-moment correlations, standard error of estimate values, intraclass correlation coefficients, Cohen κ coefficients, and the Benjamini-Hochberg procedure to compare eCRF with directly measured CRF.

RESULTS

All eCRF values from the prediction equations were associated with directly measured CRF (P < 0.01), with intraclass correlation coefficient estimates ranging from 0.07 to 0.89. Although significant agreement was found when using eCRF to categorize participants into fitness tertiles, submaximal exercise equations correctly classified an average of only 51% (range, 37%-58%) and maximal exercise equations correctly classified an average of only 59% (range, 43%-76%).

CONCLUSIONS

Despite significant associations between exercise-based prediction equations and directly measured CRF, the equations had a low degree of accuracy in categorizing participants into fitness tertiles, a key requirement when stratifying risk within a clinical setting. The present analysis highlights the limited accuracy of exercise-based determinations of eCRF and suggests the need to include cardiopulmonary measures with maximal exercise to accurately assess CRF within a clinical setting.

Reliability and Validity of a Maximal Treadmill Test for Predicting Aerobic Fitness in Norwegian Prospective Soldiers

INTRODUCTION

The Norwegian armed forces reintroduced physical fitness testing of prospective conscript soldiers in 2011. Since then, a customized maximal treadmill test (MILMAX) has been used to screen aerobic fitness in 15-20,000 young Norwegian men and women annually. The aim of the current study was to investigate reliability and validity of the MILMAX test.

MATERIALS AND METHODS

Sixty-seven young Army recruits (including 11 women) participated in this method comparison study. The subjects completed the MILMAX test twice (test-retest), consisting of walking and running at increasing speed and inclination until voluntarily exhaustion. Performance was registered as exercise tolerance time (ETT). Later, the subjects performed a treadmill test of direct maximal oxygen uptake (V̇O2max). All tests were conducted within 15 days. The study protocol was submitted to the Regional Committee for Medical and Health Research Ethics for review, prior to study initiation. The Committee considered the study to be exempted from notification. The study was carried out according to the guidelines in the Declaration of Helsinki.

RESULTS

There was no significant mean difference in MILMAX ETT between test and retest. Test-retest intraclass correlation coefficient was 0.95 (0.91, 0.97), while 95% limits of agreement was ± 60 seconds. Regression analyses showed that MILMAX ETT and gender explained 78% of the variance in directly measured V̇O2max, and a prediction equation with these two independent variables was generated. The Pearson correlation coefficient between predicted and directly measured V̇O2max was 0.89 (0.83, 0.93), while limits of agreement was ± 5.6 mL·kg-1·min-1.

CONCLUSIONS

The MILMAX is equally reliable and valid compared with well-known maximal indirect tests like the 2-mile run and the 20-m shuttle run test, and may serve as an alternative indoor test of aerobic fitness in the military, in other potentially physically strenuous occupations, or in healthy civilians.

ERS statement on standardisation of cardiopulmonary exercise testing in chronic lung diseases

The objective of this document was to standardise published cardiopulmonary exercise testing (CPET) protocols for improved interpretation in clinical settings and multicentre research projects. This document: 1) summarises the protocols and procedures used in published studies focusing on incremental CPET in chronic lung conditions; 2) presents standard incremental protocols for CPET on a stationary cycle ergometer and a treadmill; and 3) provides patients' perspectives on CPET obtained through an online survey supported by the European Lung Foundation. We systematically reviewed published studies obtained from EMBASE, Medline, Scopus, Web of Science and the Cochrane Library from inception to January 2017. Of 7914 identified studies, 595 studies with 26 523 subjects were included. The literature supports a test protocol with a resting phase lasting at least 3 min, a 3-min unloaded phase, and an 8- to 12-min incremental phase with work rate increased linearly at least every minute, followed by a recovery phase of at least 2–3 min. Patients responding to the survey (n=295) perceived CPET as highly beneficial for their diagnostic assessment and informed the Task Force consensus. Future research should focus on the individualised estimation of optimal work rate increments across different lung diseases, and the collection of robust normative data.

The document facilitates standardisation of conducting, reporting and interpreting cardiopulmonary exercise tests in chronic lung diseases for comparison of reference data, multi-centre studies and assessment of interventional efficacy.http://bit.ly/31SXeB5

Effects of intradialytic exercise on cardiopulmonary capacity in chronic kidney disease: systematic review and meta-analysis of randomized clinical trials

Patients with chronic kidney disease show poorer functional and cardiorespiratory capacity than healthy individuals, and these impairments result in sedentarism. The aim of this study was to conduct a systematic review and meta-analysis of randomized clinical trials on the effects of different intradialytic exercise protocols on cardiopulmonary capacity in chronic kidney disease patients. The primary outcome was peak oxygen consumption (VO_2peak) and the secondary outcomes were exercise duration and ventilation in the cardiopulmonary test. The quality of the evidence was evaluated using the GRADE guidelines. Seven studies with a total of 124 participants met the inclusion criteria. Compared to the non-exercise group, the exercise group improved in mean VO_2peak (MD 4.06 [IC 0.81; 7.31]). In a separate analysis according to exercise modality, aerobic exercise plus strength training performed better than aerobic exercise alone (MD 5.28 [IC 3.90; 6.66]). In the exercise group, both exercise tolerance values (MD 3.10 [IC 1.70; 4.51]) and ventilation values in the cardiopulmonary test were better than those of the control group (MD 13.10 [IC 7.12; 19.09]). Thus, intradialytic exercise protocols can improve cardiopulmonary function, exercise tolerance and ventilatory efficiency in chronic kidney disease patients.

Estimated Cardiorespiratory Fitness Is Associated With Reported Depression in College Students

Depression is a serious but treatable health issue that affects college students at an alarming rate. Improved cardiorespiratory fitness (CRF) decreases depression risk and severity but this relationship has not been fully evaluated in the college student population. Non-exercise estimated CRF (eCRF) could be used to identify students at risk for or suffering from depression. This study investigated the associations of depression and eCRF in college students. Participants (N = 437) completed a survey which included demographic and student-status questions, eCRF variables, and a validated depression instrument. Descriptive, chi-square, t-test, regression, and odds ratio analyses were employed. Depression was associated with low-fitness (X 2 = 4.660, P = 0.031) and eCRF below age-predicted CRF (t = 3.28, P < 0.001). Predictors of increased depression included low-fitness, sexual orientation, current depression treatment, and GPA (R 2 = 0.145-0.159; Adj R 2 = 0.135-0.149). Odd ratio analyses determined that low-fitness increased the risk of reporting depression (β = 2.39, P = 0.017, 95% CI = 1.17-4.872) which remained significant when adjusted (β = 2.478, P = 0.017, 95% CI = 1.175-5.229). Adjusted odds ratio analyses also indicated increased risk of reporting depression for those in a sexual minority (β = 2.582, P = 0.001, 95% CI = 1.44,4.629) and undergoing current depression treatment (β = 2.393, P < 0.001, 95% CI = 2.393-13.043). High levels of fitness did not reduce the odds of reporting depression compared to age predicted CRF. A simple eCRF algorithm can be used to identify college student depression.

Cardiorespiratory fitness as a predictor of short-term and lifetime estimated cardiovascular disease risk

Development of cardiovascular disease (CVD) remains a public health concern for young to middle-aged adults, now exacerbated by the increasing prevalence of obesity and sedentary lifestyles. Cardiorespiratory fitness (CRF) improves the reclassification of short-term (10-year) CVD risk, but has not been uniformly defined across studies. This study evaluated cross-sectional differences in short-term and lifetime CVD risk scores, across both absolute metabolic equivalent (MET) and sex- and age-standardized CRF categories in 805 apparently healthy young to middle-aged adults (68% male; 47.4 ± 7.2 years). CVD risk factors were evaluated, and estimated cardiorespiratory fitness (CRF) measurements (METS and peak VO₂ ) were derived from a submaximal Bruce treadmill test. CRF measures also included post-exercise heart rate recovery (HRR) data. Consistent trends showing more favorable risk factor profiles and lower short-term CVD (QRISK2), and CVD mortality (SCORE) scores, associated with higher levels of CRF were evident in both sexes. Lifetime CVD risk (Q-Lifetime) was highest in the lowest CRF categories. Peak VO₂ and HRR following submaximal exercise testing contributed to the variability in short-term and lifetime CVD risk. Global CVD risk predictions were examined across different contemporary CRF classifications with inconsistent findings. Recommended absolute MET and sex- and age-standardized CRF categories were significantly associated with both short-term and lifetime risk of CVD outcomes. However, compared to internationally derived normative CRF standards, cohort-specific CRF categories resulted in markedly different proportion of individuals classified in the "poor" CRF category at higher CVD risk.

High prevalence of poor fitness among Danish adults, especially among those with high cardiovascular mortality risk

Background

: Poor cardiorespiratory fitness (CRF) is an independent predictor of cardiovascular and all-cause mortality. Yet, our knowledge about the prevalence of poor CRF is limited. We investigated the prevalence of poor CRF among middle-aged Danish adults from a community-based health promotion program, including identification of a subgroup with high cardiovascular mortality risk. This cross-sectional study included 2,253 middle-aged adults, who completed a preventive health check including CRF testing. CRF (ml O 2 /min/kg) was assessed using the Astrand-Ryhming cycle ergometer test. High 10-year cardiovascular mortality risk as defined in the Danish 2016 guidelines was assessed using questionnaires, health examinations, and prescription data from the Danish National Prescription Registry. The prevalence of poor CRF was 51.7% (95% confidence interval [CI] 48.7-54.7) among men and 31.3% (95% CI 28.7-34.1) among women. A total of 216 (19.4%) men and 220 (19.3%) women were identified with a high 10-year cardiovascular mortality risk. Among these, 65.0% of men (95% CI 58.2-71.3) and 44.1% of women (95% CI 37.4-50.9) had poor CRF. Half of men and one third of women participating in a community-based health promotion program were identified with poor CRF. Among high-risk individuals, two thirds of men and almost every second woman had a poor CRF. Our results emphasise the need for effective public health strategies and interventions to increase CRF in the general population and among high-risk individuals in particular in order to improve public health and reduce mortality.

How Accurate Is the Prediction of Maximal Oxygen Uptake with Treadmill Testing?

BACKGROUND

Cardiorespiratory fitness measured by treadmill testing has prognostic significance in determining mortality with cardiovascular and other chronic disease states. The accuracy of a recently developed method for estimating maximal oxygen uptake (VO2peak), the heart rate index (HRI), is dependent only on heart rate (HR) and was tested against oxygen uptake (VO2), either measured or predicted from conventional treadmill parameters (speed, incline, protocol time).

METHODS

The HRI equation, METs = 6 x HRI- 5, where HRI = maximal HR/resting HR, provides a surrogate measure of VO2peak. Forty large scale treadmill studies were identified through a systematic search using MEDLINE, Google Scholar and Web of Science in which VO2peak was either measured (TM-VO2meas; n = 20) or predicted (TM-VO2pred; n = 20) based on treadmill parameters. All studies were required to have reported group mean data of both resting and maximal HRs for determination of HR index-derived oxygen uptake (HRI-VO2).

RESULTS

The 20 studies with measured VO2 (TM-VO2meas), involved 11,477 participants (median 337) with a total of 105,044 participants (median 3,736) in the 20 studies with predicted VO2 (TM-VO2pred). A difference of only 0.4% was seen between mean (±SD) VO2peak for TM- VO2meas and HRI-VO2 (6.51±2.25 METs and 6.54±2.28, respectively; p = 0.84). In contrast, there was a highly significant 21.1% difference between mean (±SD) TM-VO2pred and HRI-VO2 (8.12±1.85 METs and 6.71±1.92, respectively; p<0.001).

CONCLUSION

Although mean TM-VO2meas and HRI-VO2 were almost identical, mean TM-VO2pred was more than 20% greater than mean HRI-VO2.