Exercise duration: Independent effects on acute physiologic responses and the need for an individualized prescription.

An individualization of exercise prescription is implemented mainly in terms of intensity but not for duration. To survey the need for an individualized exercise duration prescription, we investigated acute physiologic responses during constant-load exercise of maximal duration (tmax ) and determined so-called duration thresholds. Differences between absolute (min) and relative terms (% tmax ) of exercise duration were analyzed. Healthy young and trained male and female participants (n = 11) performed an incremental exercise test and one tmax constant-load exercise test at a target intensity of 10% of maximal power output below the second lactate turn point (LTP2 ). Blood lactate, heart rate, and spirometric data were measured during all tests. tmax was markedly different across subjects (69.6 ± 14.8 min; range: 40-90 min). However, distinct duration phases separated by duration thresholds (DTh) were found in most measured variables. These duration thresholds (except DTh1) were significantly related to tmax (DTh2: r2  = 0.90, p < 0.0001; DTh3: r2  = 0.98, p < 0.0001) and showed substantial interindividual differences if expressed in absolute terms (DTh2: 24.8 ± 6.0 min; DTh3: 47.4 ± 10.6 min) but not in relative terms (DTh2: 35.4 ± 2.7% tmax ; DTh3: 67.9 ± 2.4% tmax ). Our data showed that (1) maximal duration was individually different despite the same relative intensity, (2) duration thresholds that were related to tmax could be determined in most measured variables, and (3) duration thresholds were comparable between subjects if expressed in relative terms. We therefore conclude that duration needs to be concerned as an independent variable of exercise prescription.

Updated Reference Standards for Cardiorespiratory Fitness Measured with Cardiopulmonary Exercise Testing: Data from the Fitness Registry and the Importance of Exercise National Database (FRIEND).

OBJECTIVE: To provide updated reference standards for cardiorespiratory fitness (CRF) for the United States derived from cardiopulmonary exercise (CPX) testing when using a treadmill or cycle ergometer. PATIENTS AND METHODS: Thirty-four laboratories in the United States contributed data to the Fitness Registry and the Importance of Exercise National Database. Analysis included 22,379 tests (16,278 treadmill and 6101 cycle ergometer) conducted between January 1, 1968, through March 31, 2021, from apparently healthy adults (aged 20 to 89 years). Percentiles of peak oxygen consumption for men and women were determined for each decade from 20 through 89 years of age for treadmill and cycle exercise modes, as well as when defining maximal effort as respiratory exchange ratio (RER) greater than or equal to 1.0 or RER greater than or equal to 1.1. RESULTS: For both men and women, the 50th percentile scores for each exercise mode decreased with age and were higher in men across all age groups and higher for treadmill compared with cycle CPX. The average rate of decline per decade over a 6-decade period was 13.5%, 4.0 mLO2·kg-1·min-1 for treadmill CPX and 16.4%, 4.3 mLO2·kg-1·min-1 for cycle CPX. Observationally, the mean peak oxygen consumption was similar whether using an RER criterion of greater than or equal to 1.0 or greater than or equal to 1.1 across the different test modes, ages, and for both sexes. The updated reference standards for treadmill CPX were 1.5 - 4.6 mLO2·kg-1·min-1 lower compared with the previous 2015 standards whereas the updated cycling standards were generally comparable to the original 2017 standards. CONCLUSION: These updated cardiorespiratory fitness reference standards improve the representativeness of the US population compared with the original standards.

Examining the repeatability of a novel test to measure exertional dyspnoea in chronic obstructive pulmonary disease.

BACKGROUND: Exertional dyspnoea(ED) is a hallmark of chronic obstructive pulmonary disease(COPD). We examined the repeatability and face validity of the end-exercise ED(EDend) response during the Dyspnoea Challenge and compared those to the six-minute walk test (6MWT) in COPD. METHODS: Twenty-six individuals with COPD(13 Females, age:69 ± 5.5yrs, FEV1:63.4 ± 11.9 %) completed 2 × 6MWTs and 4 x Dyspnoea Challenges on three occasions. The challenge consisted of a two-minute treadmill walk at 80 % of 6MWT speed(3.9 ± 0.5 km·hr-1) at either a low(LIDC:5.3 ± 2%) or high angle of incline(HIDC:9.5 ± 3%). Dyspnoea(0-10 scale), heart rate(HR) and oxygen saturation(SpO2) were monitored continuously. RESULTS: Mean 6MWT distance was 488 ± 58 m. End-exercise ED and HR were higher in the HIDC(EDend 6.2 ± 2.0; HR: 123 ± 17beats·min-1) compared to the LIDC(EDend 4.2 ± 2.0; HR: 119 ± 15beats·min-1) and the 6MWT(EDend 4.3 ± 2.0; HR: 115 ± 16beats·min-1)(P < 0.01). SpO2 was not different between 6MWT, LIDC or HIDC(P = 0.34). The intraclass correlation coefficient(ICC) for each intensity was excellent (HIDC, ICC = 0.88, LIDC, ICC = 0.93, P < 0.001) with neither reporting bias(HIDC, P = 0.63; LIDC, P = 0.94). CONCLUSIONS: The Dyspnoea Challenge is a simple measure of ED that appears to have both repeatability and face validity. With further optimisation, this test may enhance the field-based clinical assessment of ED.

Utility of the oxygen pulse in the diagnosis of obstructive coronary artery disease in physically fit patients.

Cardiopulmonary exercise testing (CPET) guidelines recommend analysis of the oxygen (O2 ) pulse for a late exercise plateau in evaluation for obstructive coronary artery disease (OCAD). However, whether this O2 pulse trajectory is within the range of normal has been debated, and the diagnostic performance of the O2 pulse for OCAD in physically fit individuals, in whom V˙O2 may be more likely to plateau, has not been evaluated. Using prospectively collected data from a sports cardiology program, patients were identified who were free of other cardiac disease and underwent clinically-indicated CPET within 90 days of invasive or computed tomography coronary angiography. The diagnostic performance of quantitative O2 pulse metrics (late exercise slope, proportional change in slope during late exercise) and qualitative assessment for O2 pulse plateau to predict OCAD was assessed. Among 104 patients (age:56 ± 12 years, 30% female, peak V˙O2 119 ± 34% predicted), the diagnostic performance for OCAD (n = 24,23%) was poor for both quantitative and qualitative metrics reflecting an O2 pulse plateau (late exercise slope: AUC = 0.55, sensitivity = 68%, specificity = 41%; proportional change in slope: AUC = 0.55, sensitivity = 91%, specificity = 18%; visual plateau/decline: AUC = 0.51, sensitivity = 33%, specificity = 67%). When O2 pulse parameters were added to the electrocardiogram, the change in AUC was minimal (-0.01 to +0.02, p ≥ 0.05). Those patients without OCAD with a plateau or decline in O2 pulse were fitter than those with linear augmentation (peak V˙O2 133 ± 31% vs. 114 ± 36% predicted, p < 0.05) and had a longer exercise ramp time (9.5 ± 3.2 vs. 8.0 ± 2.5 min, p < 0.05). Overall, a plateau in O2 pulse was not a useful predictor of OCAD in a physically fit population, indicating that the O2 pulse should be integrated with other CPET parameters and may reflect a physiologic limitation of stroke volume and/or O2 extraction during intense exercise.

Making Cardiopulmonary Exercise Testing Interpretable for Clinicians.

ABSTRACT: Cardiopulmonary exercise testing (CPET) is a dynamic clinical tool for determining the cause for a person's exercise limitation. CPET provides clinicians with fundamental knowledge of the coupling of external to internal respiration (oxygen and carbon dioxide) during exercise. Subtle perturbations in CPET parameters can differentiate exercise responses among individual patients and disease states. However, perhaps because of the challenges in interpretation given the amount and complexity of data obtained, CPET is underused. In this article, we review fundamental concepts in CPET data interpretation and visualization. We also discuss future directions for how to best use CPET results to guide clinical care. Finally, we share a novel three-dimensional graphical platform for CPET data that simplifies conceptualization of organ system-specific (cardiac, pulmonary, and skeletal muscle) exercise limitations. Our goal is to make CPET testing more accessible to the general medical provider and make the test of greater use in the medical toolbox.

Comparison of constant load exercise intensity for verification of maximal oxygen uptake following a graded exercise test in older adults.

Maximal oxygen uptake (VO2 max) declines with advancing age and is a predictor of morbidity and mortality risk. The purpose here was to assess the utility of constant load tests performed either above or below peak work rate obtained from a graded exercise test for verification of VO2 max in older adults. Twenty-two healthy older adults (9M, 13F, 67 ± 6 years, BMI: 26.3 ± 5.1 kg·m-2 ) participated in the study. Participants were asked to complete two experimental trials in a randomized, counterbalanced cross-over design. Both trials (cycle ergometer) consisted of (1) an identical graded exercise test (ramp) and (2) a constant load test at either 85% (CL85; n = 22) or 110% (CL110; n = 20) of the peak work rate achieved during the associated ramp (performed 10-min post ramp). No significant differences were observed for peak VO2 (L·min-1 ) between CL85 (1.86 ± 0.72; p = 0.679) or CL110 (1.79 ± 0.73; p = 0.200) and the associated ramp (Ramp85, 1.85 ± 0.73; Ramp110, 1.85 ± 0.57). Using the study participant's mean coefficient of variation in peak VO2 between the two identical ramp tests (2.9%) to compare individual differences between constant load tests and the associated ramp revealed 19/22 (86%) of participants achieved a peak VO2 during CL85 that was similar or higher versus the ramp, while only 13/20 (65%) of participants achieved a peak VO2 during CL110 that was similar or higher versus the ramp. These data indicate that if a verification of VO2 max is warranted when testing older adults, a constant load effort at 85% of ramp peak power may be more likely to verify VO2 max as compared to an effort at 110% of ramp peak power.

Safety and feasibility of symptom-limited cardiopulmonary exercise test using the modified Naughton protocol in children with cerebral palsy: An observational study.

ABSTRACT: Variables derived from the cardiopulmonary exercise test (CPX) provide objective information regarding the exercise capacity of children with cerebral palsy (CP), which can be used as the basis for exercise recommendations. Performing maximal CPX might not be appropriate, safe, or practical for children with CP. In the present study, the safety and feasibility of symptom-limited CPX using the modified Naughton protocol, a submaximal protocol, were investigated in children with CP, Gross Motor Function Classification System (GMFCS) level I or II. The present study included 40 children aged 6 to 12 years with CP who underwent symptom-limited CPX. CPX was performed to measure cardiopulmonary fitness using a treadmill with a modified Naughton protocol. Motor capacity was assessed using the Gross Motor Function Measure (GMFM), Pediatric Balance Scale (PBS), Timed Up and Go (TUG) test, and 6-minute walk test. Thirty-seven children with CP successfully completed testing without any adverse events during or immediately after CPX (dropout rate 7.5%). The reason for test termination was dyspnea (51.4%) or leg fatigue (48.6%). Based on the respiratory exchange ratio (RER), 21 of 37 (56.8%) children chose premature termination. The relationship between the reason for test termination and RER was not statistically significant (Spearman rho = 0.082, P = .631). CPX exercise time was strongly correlated with GMFM (Spearman rho = 0.714) and moderate correlation with PBS (Spearman rho = 0.690) and TUG (Spearman rho = 0.537). Peak oxygen uptake during CPX showed a weak correlation with GMFM and a moderate correlation with PBS. This study revealed that symptom-limited CPX using the modified Naughton protocol was safe and feasible for children with CP and GMFCS level I or II.

US School-Based Physical Fitness Assessments and Data Dissemination.

BACKGROUND: Low physical fitness (PF) levels during childhood affect healthy growth and development, and increase the risk of cardiovascular diseases. Physical education standards exist for nearly all states in the United States, but evaluation of PF in youth has yet to be systematic, reproducible, and harmonized. The purpose of this project was to describe publicly available data of school-based PF testing (SB-PFT). METHODS: A list of state-mandated SB-PFT programs published by SHAPE 2016 was confirmed by contacting appropriate authorities. SB-PFT data were obtained through each state's department of education. RESULTS: Sixteen states mandate SB-PFT, with 10 states providing publicly available data; 92% to 100% of states perform the pacer/mile, curl-up, and push-up; 54.2% to 78.5% of elementary and 44% to 66.5% of high-school youth are in the "healthy fitness zone" for aerobic capacity. CONCLUSIONS: SB-PFT provided PF data in children across the United States. The variability and inconsistency in reporting and in the values, however, raises questions about the current status of SB-PFT data and its utility in assessing PF in children. The critical nature of PF assessments is highlighted in the current COVID-19 pandemic, during which physical education has been curtailed, and emerging data demonstrate worsening of the already low levels of PF in youth.

Drop Jump? Single-Leg Squat? Not if You Aim to Predict Anterior Cruciate Ligament Injury From Real-Time Clinical Assessment: A Prospective Cohort Study Involving 880 Elite Female Athletes.

OBJECTIVE: To determine whether visually assessed performances of the single-leg squat (SLS) and vertical drop jump (VDJ) were associated with future noncontact anterior cruciate ligament (ACL) injury. DESIGN: Prognostic accuracy cohort study. METHODS: Elite female handball and football (soccer) athletes (n = 880) were tested from 2007 to 2014 and tracked through 2015. Trained physical therapists visually rated each leg during a SLS and overall control during a VDJ. Receiver operating characteristic curve, Pearson chi-square, and logistic regression analyses were used to determine the prognostic accuracy of the 2 screening tests. RESULTS: Sixty-five noncontact ACL injuries occurred during the follow-up period. Fourteen percent of athletes who sustained an ACL injury had poor SLS performance, compared to 17% of the noninjured athletes (P = .52 and .67 for hip and knee ratings, respectively). Side-to-side asymmetry in the SLS was not different between injured and noninjured athletes (P = .10 and .99 for hip and knee asymmetry, respectively). Twenty-one percent of athletes who sustained an ACL injury had a poor VDJ rating, compared to 27% of the noninjured athletes (P = .09). Furthermore, area under the curve values ranged from 0.43 to 0.54 for the SLS and VDJ, demonstrating no to poor prognostic accuracy. CONCLUSION: Neither SLS nor VDJ test performance distinguished between athletes who sustained a subsequent noncontact ACL injury and those who did not. J Orthop Sports Phys Ther 2021;51(7):372-378. doi:10.2519/jospt.2021.10170.

Short Physical Performance Battery: Response to Pulmonary Rehabilitation and Minimal Important Difference Estimates in Patients With Chronic Obstructive Pulmonary Disease.

OBJECTIVE: To determine the response to a pulmonary rehabilitation (PR) program and minimal important differences (MIDs) for the Short Physical Performance Battery (SPPB) subtests and SPPB summary score in patients with chronic obstructive pulmonary disease (COPD). DESIGN: Retrospective analysis using distribution- and anchor-based methods. SETTING: PR center in the Netherlands including a comprehensive 40-session 8-week inpatient or 14-week outpatient program. PARTICIPANTS: A total of 632 patients with COPD (age, 65±8y; 50% male; forced expiratory volume in the first second=43% [interquartile range, 30%-60%] predicted). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Baseline and post-PR results of the SPPB, consisting of 3 balance standing tests, 4-meter gait speed (4MGS), and 5-repetition sit-to-stand (5STS). The chosen anchors were the 6-Minute Walk Test and COPD Assessment Test. Patients were stratified according to their SPPB summary scores into low-performance, moderate-performance, and high-performance groups. RESULTS: 5STS (∆=-1.14 [-4.20 to -0.93]s) and SPPB summary score (∆=1 [0-2] points) improved after PR in patients with COPD. In patients with a low performance at baseline, balance tandem and 4MGS significantly increased as well. Based on distribution-based calculations, the MID estimates ranged between 2.19 and 6.33 seconds for 5STS and 0.83 to 0.96 points for SPPB summary score. CONCLUSIONS: The 5STS and SPPB summary score are both responsive to PR in patients with COPD. The balance tandem test and 4MGS are only responsive to PR in patients with COPD with a low performance at baseline. Based on distribution-based calculations, an MID estimate of 1 point for the SPPB summary score is recommended in patients with COPD. Future research is needed to confirm MID estimates for SPPB in different centers.

A systematic review of exercise testing in patients with intermittent claudication: A focus on test standardisation and reporting quality in randomised controlled trials of exercise interventions.

A systematic review was conducted to identify the range of terminology used in studies to describe maximum walking distance and the exercise testing protocols, and testing modalities used to measure it in patients with intermittent claudication. A secondary aim was to assess the implementation and reporting of the exercise testing protocols. CINAHL, Medline, EMBASE and Cochrane CENTRAL databases were searched. Randomised controlled trials whereby patients with intermittent claudication were randomised to an exercise intervention were included. The terminology used to describe maximal walking distance was recorded, as was the modality and protocol used to measure it. The implementation and reporting quality was also assessed using pre-specified criteria. Sixty-four trials were included in this review. Maximal walking distance was reported using fourteen different terminologies. Twenty-two different treadmill protocols and three different corridor tests were employed to assess maximal walking distance. No single trial satisfied all the implementation and reporting criteria for an exercise testing protocol. Evidence shows that between-study interpretation is difficult given the heterogenous nature of the exercise testing protocols, test endpoints and terminology used to describe maximal walking distance. This is further compounded by poor test reporting and implementation across studies. Comprehensive guidelines need to be provided to enable a standardised approach to exercise testing in patients with intermittent claudication.

Cardiopulmonary exercise testing during the COVID-19 pandemic.

The outbreak of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has presented a global public health emergency. Although predominantly a pandemic of acute respiratory disease, corona virus infectious disease-19 (COVID-19) results in multi-organ damage that impairs cardiopulmonary (CP) function and reduces cardiorespiratory fitness. Superimposed on the CP consequences of COVID-19 is a marked reduction in physical activity that exacerbates CP disease (CPD) risk. CP exercise testing (CPET) is routinely used in clinical practice to diagnose CPD and assess prognosis; assess cardiovascular safety for rehabilitation; and delineate the physiological contributors to exercise intolerance and exertional fatigue. As such, CPET plays an important role in clinical assessments of convalescent COVID-19 patients as well as research aimed at understanding the long-term health effects of SARS-CoV-2 infection. However, due to the ventilatory expired gas analysis involved with CPET, the procedure is considered an aerosol generating procedure. Therefore, extra precautions should be taken by health care providers and exercise physiologists performing these tests. This paper provides recommendations for CPET testing during the COVID-19 pandemic. These recommendations include indications for CPET; pre-screening assessments; precautions required for testing; and suggested decontamination protocols. These safety recommendations are aimed at preventing SARS-CoV-2 transmission during CPET.

Edmonton Obesity Staging System: an improvement by cardiopulmonary exercise testing.

BACKGROUND/OBJECTIVES: Different approaches are used to classify obesity severity. Beyond classical anthropometric measurements, the Edmonton Obesity Staging System (EOSS) considers medical, physical and psychological parameters. However, this method has some limitations, principally due to the absence of an objective measure for physical impairment. The aim of our study is thus to overcome this limitation suggesting a new functional parameter obtained by cardiopulmonary exercise testing (CPET), i.e., cardiorespiratory fitness (CRF), expressed as weight-adjusted peak oxygen consumption (VO2peak/kg). SUBJECTS/METHODS: This observational cross-sectional study conducted on a population of 843 patients affected by obesity finally enrolled 500 subjects. Every patient underwent clinical, anthropometric, biochemical assessment and CPET. First, participants have been classified according to standard EOSS in five stages. Second, patients were reclassified according to the new modified EOSS (EOSS-CRF) based on their age- and gender-appropriate VO2peak/kg percentiles as reported in the healthy normal-weight population of the FRIEND registry. RESULTS: VO2peak/kg was significantly different between standard EOSS classes 1 and 2 and classes 1 and 3 (ANCOVA p model = 0.004), whereas patients in classes 2 and 3 showed similar CRF. The EOSS-CRF classification varied in number of patients in each class compared to EOSS, particularly with a shift from class 2 to class 3. Moreover, CRF showed that physical impairment is less addressed by EOSS when compared to EOSS-CRF. CONCLUSIONS: The integration of EOSS with CRF allowed us to assign to each patient a severity index that considers not only clinical parameters, but also their functional impairment through a quantitative and prognostically important parameter (VO2peak/kg). This improvement of the staging system may also provide a better approach to identify individuals at increased risk of mortality leading to targeted therapeutic management and prognostic risk stratification for patients with obesity.

Criterion Validity and Responsiveness of the Steep Ramp Test to Evaluate Aerobic Capacity in Survivors of Cancer Participating in a Supervised Exercise Rehabilitation Program.

OBJECTIVE: To evaluate the criterion validity and responsiveness of the steep ramp test (SRT) compared with the cardiopulmonary exercise test (CPET) in evaluating aerobic capacity in survivors of cancer participating in a rehabilitation program. DESIGN: A prospective cohort study in which survivors of cancer performed an SRT and CPET before (T=0) and after (T=1) a 10-week exercise rehabilitation program. Peak work rate achieved during the SRT (SRT-WRpeak) was compared with peak oxygen consumption measured during the CPET (CPET-Vo2peak), which is the criterion standard for aerobic capacity. Correlation coefficients were calculated between SRT-WRpeak and CPET-Vo2peak at T=0 to examine criterion validity and between changes in SRT-WRpeak and CPET-Vo2peak from T=0 to T=1 to determine responsiveness. Receiver operating characteristic analysis was performed to examine the ability of the SRT to detect a true improvement (6%) in CPET-Vo2peak. SETTING: University medical center. PARTICIPANTS: Survivors of cancer (N=106). INTERVENTIONS: Exercise rehabilitation. MAIN OUTCOME MEASURES: Correlation coefficients between CPET-Vo2peak and SRT-WRpeak and between changes in CPET-Vo2peak and SRT-WRpeak. RESULTS: An r of 0.86 (N=106) was found for the relation between SRT-WRpeak and CPET-Vo2peak at T=0. An r of 0.51 was observed for the relation between changes in SRT-WRpeak and CPET-Vo2peak (n=59). Receiver operating characteristic analysis showed an area under the curve of 0.74 for the SRT to detect a true improvement in CPET-Vo2peak, with an optimal cutoff value of +0.26 W/kg (sensitivity 70.7%, specificity 66.7%). CONCLUSIONS: Because SRT-WRpeak and CPET-Vo2peak were strongly correlated, the SRT seems a valid tool to estimate aerobic capacity in survivors of cancer. The responsiveness to measure changes in aerobic capacity appears moderate. Nevertheless, the SRT seems able to detect improvement in aerobic capacity, with a cutoff value of 0.26 W/kg.

Effect of treatment of peripheral arterial disease on the onset of anaerobic exercise during cardiopulmonary exercise testing.

OBJECTIVE: Cardiopulmonary exercise testing (CPET) is often used to assess pre-operative fitness in elderly patients, in whom peripheral arterial disease (PAD) is highly prevalent, but may affect the results of CPET by early lactate release due to muscle ischemia. This study investigated the effect revascularization of PAD on oxygen delivery (VO2 ) during CPET. METHOD: We conducted a prospective cohort study of 30 patients, who underwent CPET before and after treatment of ilio-femoral PAD. The primary outcome measure was difference in VO2 at the lactate threshold (LT) before and after revascularization. Secondary outcome measures were the relationship between change in VO2 at LT and peak exercise and change in ankle-brachial index (ABI) differential. RESULTS: The study was approved by the North West-Lancaster Research and Ethics committee (reference 15/NW/0801) and registered in clinicaltrial.gov (reference NCT02657278). As specified in the study protocol, 30 patients were recruited but only 20 (15 men), with a mean age of 62 years, completed pre- and post-treatment CPETs. Twelve patients demonstrated an improvement in VO2 at LT after revascularization, but the difference did not achieve statistical significance (mean difference (95% CI) = 1.43 (-0.21 to 3.08) ml/kg/min; (p = 0.085). There was, however, a significant improvement in VO2 , VE/CO2 , workload and Borg breathlessness and leg fatigue score at peak exercise after revascularization. There was no significant correlation between change in VO2 at LT (r = -0.11, p = 0.65) or change in VO2 at peak and ABI differential (r = -0.14, p = 0.55). CONCLUSION: Revascularization of PAD led to significant improvement in multiple peak/maximal exercise parameters within a few weeks and without exercise training. We were unable to demonstrate a statistically significant improvement in VO2 at LT albeit in a majority of subjects this exceeded what we pre-defined as clinically significant.

Current limits for flowmeter resistance in metabolic carts can negatively affect exercise performance.

PURPOSE: To investigate whether a metabolic cart using a flowmeter in the upper range of accepted resistance to airflow (<1.5 cmH2 O∙L-1 ∙s-1 for flows up to 14 L∙s-1 , American Thoracic Society) negatively impacts exercise performance in healthy individuals. METHODS: 16 recreationally active males (age 25 ± 1 years, height 180 ± 6 cm, weight 73.5 ± 5.8 kg, all mean ± SD) performed two incremental tests on a bicycle ergometer on each of two visits, using a metabolic cart with a flowmeter of either low (Oxycon Pro) or high (Innocor) airflow resistance. Mouth pressures, gas exchange, blood lactate concentration [La- ], perception of breathlessness, respiratory, and leg exertion were assessed throughout the tests. RESULTS: Tests performed with the Innocor were significantly shorter (15.3 ± 3.2 vs. 15.8 ± 3.3 min, p < 0.0001) and showed higher maximal flow resistance (1.3 ± 0.2 vs. 0.3 ± 0.0 cmH2 O∙L-1 ∙s-1 , p < 0.0001). At end-exercise, peak oxygen consumption (-200 ± 220 ml.min-1 , p < 0.0001), minute ventilation (-19.9 ± 10.5 L.min-1 , p < 0.0001), breathing frequency (-5.4 ± 5.2 breaths.min-1 , p < 0.0001), heart rate (-2.1 ± 3.6 bpm, p = 0.002) and [La- ] (-0.7 ± 1.0 mmol.L-1 , p < 0.0001), but not tidal volume (-0.1 ± 0.2 L, p = 0.172) were lower with the Innocor, while the perception of breathlessness was higher (+3.8 ± 5.1 points, p < 0.0001). CONCLUSIONS: Airflow resistance in the upper range of current guidelines can significantly affect exercise performance and respiratory pattern in young, healthy males during incremental exercise. The present results indicate the need to revisit guidelines for devices used in ergospirometry.

Biomechanical upper-extremity performance tests and isokinetic shoulder strength in collision and contact athletes.

The aim of this study was threefold (1) to assess the reliability of three upper-extremity performance tests: a countermovement push up, press jump and drop box land, performed on a set of dual-force plates (2) to examine whether there was an association between isokinetic dynamometry and the performance tests in a non-injured cohort of collision/contact athletes and (3) to establish a normal descriptive profile of the vertical ground reaction forces from the performance tests, in a cohort of contact/collision athletes. The study was split into two sub-sections; the inter-day reliability of three upper-extremity performance tests (n = 21) and a descriptive, correlation study investigating the relationship between isokinetic dynamometry and performance tests metrics (n = 39). We used intraclass correlation coefficients (absolute agreement, 2-way mixed-effects model) with 95% confidence intervals to quantify inter-day reliability of all variables. We used Pearson correlation coefficients to investigate associations between isokinetic strength and vertical ground reaction force asymmetry variables. Inter-day reliability was moderate-to-excellent for the upper-extremity performance tests (ICC 0.67-0.97). There was no statistically significant correlation between external and internal rotational peak torque and the variables of CPMU, PJ and BDL (r range = .02-.24).These upper-extremity tests are reliable for use with male contact/collision athletes.

Reliability of five trunk flexion and extension endurance field-based tests in high school-aged adolescents: ISQUIOS programme.

This study aimed to explore the inter-session reliability of the measures obtained from 2 trunk extension (Biering-Sorensen and Dynamic Extensor Endurance (DEE) tests) and 3 trunk flexion (Ito, Side Bridge and Bench Trunk Curl-Up (BTC) tests) endurance field-based tests in adolescents. A total of 208 (males, n = 100; females, n = 108) adolescents performed all the field-based tests on 2 separate testing sessions, 7-days apart. The inter-session reliability scores were explored through relative reliability, inter-session differences and precision of measurements. Most of the trunk endurance measures demonstrated acceptable relative reliability (the intraclass correlation coefficients (ICC) ranged from 0.75 to 0.94). However, significant inter-session differences were identified for measures from the DEE and BTC tests. Likewise, the precision of the measurement of each field-based test was poor (the the standard error of measurement expressed as a percentage of the mean score (CVTE) ranged from 11.3 to 24.4%) with the minimal detectable change (MDC95) revealing that changes higher than 42% for trunk extension endurance tests and 31.4% for trunk flexion endurance tests after an intervention are required to indicate a significant change above measurement error. Therefore, the findings from this study indicate that only the BTC test demonstrates acceptable inter-session reliability (ICC > 0.9, CVTE ~ 10%, MDC95 ~ 30%) to monitor the changes in trunk endurance scores that may be expected in adolescents after performing an intervention programme.

Application of the Modified Incremental Step Test for Pulmonary Rehabilitation.

OBJECTIVE: A Modified Incremental Step Test (MIST) performed in the home may facilitate entirely home-based pulmonary rehabilitation programs. The aims of this study were to investigate the reliability and responsiveness, and the utility of the MIST for exercise prescription in people with stable chronic lung disease. METHODS: The MIST was undertaken at the center and home in random order, before and after pulmonary rehabilitation, with 2 tests at each time point. Reliability was assessed using intraclass correlation coefficient. Responsiveness was evaluated as effect size. The minimal important difference was appraised using distribution and anchor-based methods. In a substudy, physiological responses to MIST were measured by a portable metabolic system, followed by a constant step rate test at 60% of peak oxygen uptake (VO2peak), to evaluate utility for exercise prescription. RESULTS: Forty-six participants were recruited (29% of eligible candidates). There was excellent reliability for number of steps recorded in home- and center-based settings (intraclass correlation coefficient = 0.954, 95% CI = 0.915-0.976). A small-moderate effect size was demonstrated following pulmonary rehabilitation (0.34), and the minimal detectable change was 7 steps. All participants in the substudy achieved 60% of VO2peak and achieved steady state by the fourth minute, with 60% of VO2peak corresponding to a mean 37% (95% CI = 29-44) of the MIST final level. CONCLUSIONS: The MIST is reliable and responsive to pulmonary rehabilitation in people with stable chronic respiratory disease. It provides new opportunities to assess exercise capacity, prescribe exercise training, and reassess exercise program outcomes in environments where established field walking tests are not feasible. IMPACT: Pulmonary rehabilitation is a highly effective treatment that is underutilized worldwide. Home-based pulmonary rehabilitation may improve access for patients and deliver equivalent clinical outcomes but is limited by the availability of a robust exercise test that can be used at home to assess exercise capacity and prescribe training intensity. This study tested the clinimetric properties of the MIST and demonstrated a new way to assess exercise capacity, prescribe exercise training of an appropriate intensity, and reassess exercise capacity in environments where established field walking tests are not feasible.

Reference values for maximum oxygen uptake relative to body mass in Dutch/Flemish subjects aged 6-65 years: the LowLands Fitness Registry.

BACKGROUND: The maximum oxygen uptake (VO2max) during cardiopulmonary exercise testing (CPET) is considered the best measure of cardiorespiratory fitness. AIM: To provide up-to-date reference values for the VO2max per kilogram of body mass (VO2max/kg) obtained by CPET in the Netherlands and Flanders. METHODS: The Lowlands Fitness Registry contains data from health checks among different professions and was used for this study. Data from 4612 apparently healthy subjects, 3671 males and 941 females, who performed maximum effort during cycle ergometry were analysed. Reference values for the VO2max/kg and corresponding centile curves were created according to the LMS method. RESULTS: Age had a negative significant effect (p < .001) and males had higher values of VO2max/kg with an overall difference of 18.0% compared to females. Formulas for reference values were developed: Males: VO2max/kg = - 0.0049 × age2 + 0.0884 × age + 48.263 (R2 = 0.9859; SEE = 1.4364) Females: VO2max/kg = - 0.0021 × age2 - 0.1407 × age + 43.066 (R2 = 0.9989; SEE = 0.5775). Cross-validation showed no relevant statistical mean difference between measured and predicted values for males and a small but significant mean difference for females. We found remarkable higher VO2max/kg values compared to previously published studies. CONCLUSIONS: This is the first study to provide reference values for the VO2max/kg based on a Dutch/Flemish cohort. Our reference values can be used for a more accurate interpretation of the VO2max in the West-European population.