The talk test as a useful tool to monitor aerobic exercise intensity in healthy population

The talk test (TT) is subjective method to measure exercise intensity in costless and feasible manner, compared to sophisticated laboratory equipment. We attempted to investigate whether the TT was a valid method for evaluation of exercise intensity, by comparing with values derived from various physiologic markers during cardiopulmonary exercise testing on treadmill in healthy population. A total of 17 healthy subjects (12 males and 5 females) participated in this study. The TT was applied, which consisted of 3-stages difficulties demanding respiratory load while they performed the cardiopulmonary exercise testing on treadmill. In each of the TT stages, ergospirometric and psychophysiologic response marker were collected such as heart rate, oxygen consumption, respiratory exchange ratio, minute ventilation, carbon dioxide output, tidal volume, respiratory rate, and rating of perceived exertion of breathing. Statistical analyses revealed a significant difference of all dependent variables in each of three TT stages, comparing with the resting phase before the TT. The TT showed strong correlation coefficient with all variables except for rating of perceived exertion during the resting phase before the TT. According to increase of exercise intensity, all dependent variables showed a linear tendency with the stages of the TT. Our findings indicated that each of the TT stages was strongly correlated with ergospirometric variables as well as psychophysiologic response during cardiopulmonary exercise testing on treadmill. We suggested that the TT can be used to evaluate and prescribe exercise intensity of aerobic activity in cardiovascular and pulmonary rehabilitation settings.

Effect of concurrent training in unilateral transtibial amputees using Paralympic athletes as a control group

CONTEXT

Transtibial Amputation (TA) predisposes to a sedentary lifestyle.

OBJECTIVES

To evaluate the efficiency of a short-term (8-week) Concurrent Training (CT) program in Unilateral Transtibial Amputees (UTA) and to compare it with the physical condition of a group of Paralympic athletes in preparation for the Rio de Janeiro Paralympics.

DESIGN

This was a longitudinal, prospective and controlled trial study.

METHODS

Thirty-four male subjects with UTA and using prostheses for six months or more were selected for this study. They were divided into two groups: Group 1 (G1) ‒ 17 non-athlete and untrained UTA and Group 2 (G2) ‒ 17 paralympic athletes with active UTA in the training phase. G1 was evaluated before and after eight weeks of CT and G2 made a single evaluation for control. All were submitted to anamnesis, clinical evaluation (blood pressure, electrocardiogram, and heart rate) and cardiopulmonary exercise testing on a lower limb cycle ergometer, and isokinetic knee dynamometry. The CT of G1 included resistance exercise and aerobic interval training on a stationary bicycle and G2 followed the training of the Paralympic teams.

RESULTS

Patients were retested by the same methods after CT. The two most important central dependent variables (maximal oxygen uptake and muscular strength) increased by 22% and knee extensor and flexor strength by 106% and 97%, respectively.

CONCLUSION

After eight weeks of CT, there was an improvement in general functional condition, muscle strength, and cardiorespiratory performance improving protection against chronic diseases and quality of life.

Effects of neuromuscular electrical stimulation on torque and performance in recreational distance runners: A randomized controlled trial

INTRODUCTION

Neuromuscular electrical stimulation (NMES) is used by athletes to improve muscle performance. However, evidence on the use of NMES in long distance runners is scarce. As such, this study aimed to evaluate the effects of NMES on the muscle torque and sports performance of long-distance recreational runners.

METHODS

This was a blinded randomized controlled trial. Data from 30 volunteers were analyzed. Participants were randomly allocated to an experimental (n = 15) or control group (n = 15). The experimental group was submitted to running training (RT) and a strengthening protocol with NMES (1 kHz, modulated in 2 ms bursts, 50 Hz modulated burst frequency and 10% duty cycle, 15 min totaling 18 contractions per sessions) for 6 weeks, with 3 sessions per week, while controls were submitted to RT alone. The following variables were analyzed: peak isometric (ISO), concentric (CON), and eccentric (ECC) torque of the quadriceps muscle in voluntary contractions, ventilatory anaerobic thresholds (VATs), maximal oxygen uptake (VO2max), and oxygen cost of transport (OCT).

RESULTS

The NMES group obtained higher values of ISO, 21.04% (p = 0.001), CON, 21.97% (p = 0.001) and ECC, 18.74% (p = 0.001) peak torque and VAT1, 9.56% (p = 0.001), as well as a statistically significant improvement in oxygen cost of transport at VAT1 when compared to controls (p = 0.001).

CONCLUSION

NMES was effective in improving peak isometric, concentric and eccentric quadriceps muscle torque, in addition to being an interesting resource for enhancing sports performance in long-distance recreational runners and future clinical trials should be performed to compare the use of NMES to different forms of training over longer training periods.

Comparative analysis between available challenge tests in the hyperventilation syndrome

BACKGROUND

The hyperventilation syndrome (HVS) is characterized by somatic/ psychological symptoms due to sustained hypocapnia and respiratory alkalosis without any organic disease.

OBJECTIVE

The purpose of this study was to compare ventilatory parameters and symptoms reproducibility during the hyperventilation provocation test (HVPT) and cardiopulmonary exercise test (CPET) as diagnostic tools in patients with HVS, and to identify the most frequent etiologies of the HVS by a systematic assessment.

METHODS

After exclusion of organic causes, 59 patients with HVS according to Nijmegen's questionnaire (NQ) score ≥23 with associated hypocapnia (PaCO₂/PET_CO2<35 mm Hg) were studied.

RESULTS

The most frequent comorbidities of HVS were anxiety and asthma (respectively 95% and 73% of patients). All patients described ≥3 symptoms of NQ during the HVPT vs 14% of patients during the CPET (p<0.01). For similar maximal ventilation (61 L/min during HVPT vs 60 L/min during CPET), the median level of PET_CO2 decreased from 30 mmHg at baseline to 15 mmHg during hyperventilation and increased from 31 mmHg at baseline to 34 mmHg at peak exercise (all p<0.01). No significant difference for the ventilatory parameters was found between patients with HVS (n = 16) and patients with HVS + asthma (n = 43).

CONCLUSIONS

In term of symptoms reproducibility, HVPT is a better diagnostic tool than CPET for HVS. An important proportion of patients with HVS has an atypical asthma previously misdiagnosed. The exercise-induced hyperventilation did not induce abnormal reduction in PET_CO2, suggesting that the exercise could be a therapeutic tool in HVS.

Exercise energy expenditure in patients with idiopathic pulmonary arterial hypertension: Impact on clinical severity and survival

Patient with idiopathic pulmonary hypertension (IPAH) develop peripheral inefficiency which could lead to an increase total energy expenditure and that could have a significant prognostic impact. To test the hypothesis, fifty-five consecutive stable IPAH patients (mean age 51±17 years) and 24 matched controls underwent an incremental exercise test and followed for a 5 years' period. Total energy expenditure was assessed as the ratio between total [Formula: see text] uptake (during both effort and recovery) and total external work ( [Formula: see text] ). Patients with IPAH had a lower exercise capacity and a significantly higher [Formula: see text] than controls ( [Formula: see text] 0.33 ± 0.09 ml/j vs 0.22 ± 0.04 ml/j, p < 0.0001). Among patients, [Formula: see text] was higher in whom died during follow up compared to survivors (0.41 ± 0.11 ml/j vs 0.30 ± 0.06 ml/j, p < 0.0001). In multivariate Cox regression analysis [Formula: see text] , gender, P_ETCO_{2 peak}, [Formula: see text] were independent risk factors for death. Patients with IPAH have shown a less efficient muscular oxygen utilization than controls. Notably the high energy expenditure has a relevant independent prognostic impact.

Respiratory Training Late After Fontan Intervention: Impact on Cardiorespiratory Performance

Fontan palliation allows patients with "single ventricle" circulation to reach adulthood with an acceptable quality of life, although exercise tolerance is significantly reduced. To assess whether controlled respiratory training (CRT) increases cardiorespiratory performance. 16 Adolescent Fontan patients (age 17. 5 ± 3.8 years) were enrolled. Patients were divided into CRT group (n = 10) and control group (C group, n = 6). Maximal cardiopulmonary test (CPT) was repeated at the end of CRT in the CRT group and after an average time of 3 months in the C group. In the CRT group a CPT endurance was also performed before and after CRT. In the CRT group there was a significant improvement in cardiovascular and respiratory response to exercise after CRT. Actually, after accounting for baseline values, the CRT group had decreased breathing respiratory reserve (- 15, 95% CI -22.3 to - 8.0, p = 0.001) and increased RR peak (+ 4.8, 95% CI 0.7-8.9, p = 0.03), VE peak (+ 13.7, 95% CI 5.6-21.7, p = 0.004), VO₂ of predicted (+ 8.5, 95% CI 0.1-17.0, p = 0.05), VO₂ peak (+ 4.3, 95% CI 0.3 to 8.2, p = 0.04), and VO₂ workslope (+ 1.7, 95% CI 0.3-3.1, p = 0.02) as compared to the control group. Moreover, exercise endurance time increased from 8.45 to 17.7 min (p = 0.01). CRT improves cardiorespiratory performance in post-Fontan patients leading to a better aerobic capacity.

Oxygen Consumption (V'O2) and physical Strainas measured by the occupational activity of cleaning personnel

Background

The aim of the study was to determine the physical effort and energy expenditure needed over a working period of 45–60 min, specifically for the occupational activity of cleaning. The effort was demonstrated in absolute terms (V’O2), in relation to the involved person’s maximum physical capacity (peak V’O2) and in relation to the individual aerobic-anaerobic threshold (V’O2 at VT1, the point when lactate starts to accumulate but can be cleared). In addition to this, the aim was to verify the suitability of portable ergospirometry in determining the occupational workload in a real-life setting.

Methods

Thirty-five cleaners performed a bicycle ergospirometry to determine their maximum physical capacity (peak V’O2 = L/min) and their aerobic-anaerobic threshold (V’O2 at the Ventilatory Threshold 1 [VT1]). This was followed by portable ergospirometry lasting 45–60 min while pursuing regular cleaning activities.

Results

Performance V’O2 (the average oxygen consumption over 45–60 min of work- time) was 1.06 L/min or 4.4 METs. This was scarcely lower than the individual V’O2 at VT1 and approached 45% of the maximum physical capacity (peak V’O2). In addition, there was positive feedback regarding the wearability of the portable device. The dropout rate was low.

Conclusion

The occupational activity of cleaning was defined as a “committed activity”, performed close to the upper limit of the continuous physical capacity (approaching V’O2 at VT1). The positive feedback and a low dropout rate proved good acceptance of portable ergospirometry in this field of work over a 45–60 min period.

Lung function development after preterm birth in relation to severity of Bronchopulmonary dysplasia

BACKGROUND

Bronchopulmonary dysplasia (BPD) is a strong risk factor for respiratory morbidity in children born preterm. Our aims were to evaluate lung function in adolescents born preterm with and without a history of BPD, and to assess lung function change over time from school age.

METHODS

Fifty-one individuals born in Stockholm, Sweden between gestational ages 24 to 31 weeks (23 neonatally diagnosed with respiratory distress syndrome (RDS) but not BPD, and 28 graded as mild (n = 17), moderate (n = 7) or severe (n = 4) BPD) were examined in adolescence (13-17 years of age) using spirometry, impulse oscillometry (IOS), plethysmography, and ergospirometry. Comparison with lung function data from school age (6-8 years of age) was also performed.

RESULTS

Adolescents with a history of BPD had lower forced expiratory volume in 1 s (FEV₁) compared to those without BPD (-0.61 vs.-0.02 z-scores, P < 0.05), with lower FEV₁ values significantly associated with BPD severity (P for trend 0.002). Subjects with severe BPD had higher frequency dependence of resistance, R_5-20, (P < 0.001 vs. non-BPD subjects) which is an IOS indicator of peripheral airway involvement. Between school age and adolescence, FEV₁/FVC z-scores decreased in all groups and particularly in the severe BPD group (from -1.68 z-scores at 6-8 years to -2.74 z-scores at 13-17 years, p < 0.05 compared to the non-BPD group).

CONCLUSIONS

Our results of spirometry and IOS measures in the BPD groups compared to the non-BPD group suggest airway obstruction including involvement of peripheral airways. The longitudinal result of a decrease in FEV₁/FVC in the group with severe BPD might implicate a route towards chronic airway obstruction in adulthood.

Phosphodiesterase-5 Inhibitors Improve Clinical Outcomes, Exercise Capacity and Pulmonary Hemodynamics in Patients With Heart Failure With Reduced Left Ventricular Ejection Fraction: A Meta-Analysis

BACKGROUND

Several studies have compared the use of phosphodiesterase-5 (PDE5) inhibitors sildenafil or udenafil with the placebo in patients suffering from pulmonary hypertension (PH) due to left chronic heart failure (CHF), corresponding to group 2 (PH due to left heart disease) of the PH classification (according to 2015 ESC/ERS guidelines for the diagnosis and treatment of PH). The results of the use of PDE5 inhibitors in the PH due to left heart disease were inconsistent and heterogeneous. Therefore, we carried out a meta-analysis to assess the effect of PDE5 inhibitors in this clinical setting, i.e., patients with left CHF.

METHODS

A systematic search was conducted using the PubMed and Embase electronic archives. Studies had to be prospective randomized controlled trials (RCTs). In each of the RCTs admitted to meta-analysis, a comparison was made between a group of CHF patients taking a PDE5 inhibitor and a second group assigned a placebo. Studies were incorporated in the meta-analysis provided that they had sufficient information about two or more of the following clinical, ergospirometric or hemodynamic outcomes: the composite of all-cause death and hospitalization, adverse events, peak VO₂, 6-min walking distance (6MWD), left ventricular ejection fraction (LVEF), E/e' ratio, mean pulmonary arterial pressure (mPAP), pulmonary arterial systolic pressure (PASP), and pulmonary vascular resistance (PVR).

RESULTS

Fourteen studies enrolling a total of 928 patients were incorporated in the meta-analysis. Among them,13 were RCTs and one was a subgroup analysis. Among patients with CHF with reduced left ventricular ejection fraction (HFREF, n = 555), a significant benefit was conferred by PDE5 inhibitors against the risk of the composite endpoint of death and hospitalizations (odds ratio (OR): 0.28; 95% confidence interval (CI): 0.10 - 0.74; P = 0.03). Furthermore, among HFREF patients, PDE5 inhibitors were associated with a significant improvement in peak VO₂ (difference in means (MD): 3.76 mL/min/kg; 95% CI: 3.27 - 4.25) as well as in 6MWD (MD: 22.7 m; 95% CI: 8.19 - 37.21) and LVEF (MD: 4.30%; 95% CI: 2.18% to 6.42%). For patients with HFREF, PDE5 inhibitors caused a non-significant reduction in mPAP, while PASP was significantly reduced (MD: -11.52 mm Hg; 95% CI: -15.56 to -7.49; P < 0.001). By contrast, in the RCTs of patients with CHF with preserved left ventricular ejection fraction (HFpEF, n = 373), no benefit ensued from PDE5 inhibitor use regarding all of the investigated clinical, ergospirometric or hemodynamic endpoints.

CONCLUSIONS

PDE5 inhibitors improved clinical outcomes, exercise capacity and pulmonary hemodynamics in patients with HFREF, but not in HFpEF. However, considering the relatively small size of the HFpEF subset enrolled so far in the RCTs that explored the PDE5 inhibitor effects, further research in this field is undoubtedly warranted.

Misinterpretation of the Borg's Rating of Perceived Exertion Scale by patients with panic disorder during ergospirometry challenge

INTRODUCTION

The most widely used instrument to measure perceived exertion or exercise intensity is the Borg's Rating of Perceived Exertion (RPE) Scale. Panic attacks are aversive experiences that may be triggered by bodily sensations such as palpitations, breathlessness or dizziness due to increasing autonomic distress, prior sensitisation to panic and fear conditioning. The consequence is catastrophic interpretation of bodily sensations of arousal in general, which can lead to misinterpretation of exertion or exercise intensity.

PURPOSE

To verify the effectiveness of the Borg's RPE Scale as a measure of perceived effort in panic disorder subjects.

METHODS

The study enrolled 72 subjects: the control group (C, healthy sedentary subjects, n=30) and patients with panic disorder (PD, n=42). All subjects were submitted to an ergospirometry challenge. Perceived exertion RPE scores and heart rate at 90% VO2max were compared between groups.

RESULTS

Patients with PD showed lower levels of maximal oxygen consumption, when compared with C group [VO₂max (mL/kg/min): PD=29.42±6.50xC=34.51±5.35; Student's t-test=-3.51; p <0.05]. Furthermore, among PD subjects, the maximum heart rate during ergospirometry challenge was lower than expected [predict max HR (bpm)=200.85±6.33xheart rate test (bpm)=178.86±7.28; Z=-5.64; p<0.05]. Perceived exertion, as measured by RPE, was also overestimated in relation to heart rate at 90% of maximum oxygen consumption compared with controls (RPE90%VO₂max: PD=18.93±0.55xC=16.67±0.60; U=8.00; Z=7.42; p<0.05).

CONCLUSIONS

The present study findings suggest that the Borg's RPE Scale may not be an appropriate measure of subjective exertion among subjects with panic disorder performing a cardiopulmonary exercise test.

Evaluation of a New Shirt-Based Electrocardiogram Device for Cardiac Screening in Soccer Players: Comparative Study With Treadmill Ergospirometry

Background

Prevention of cardiac events during competitive sports is fundamental. New technologies with remote monitoring systems integrated into clothing could facilitate the screening of heart disease. Our aim was to evaluate the feasibility of Nuubo system during a field stress test performed by soccer players, comparing results with treadmill ergospirometry as test reference.

Methods

Nineteen male professional soccer players (19.2 ± 1.6 years) were studied. Wireless electrocardiographic monitoring during a Yo-Yo intermittent recovery test level 1 in soccer field and subsequent analysis of arrhythmias were firstly performed. Subsequently, in a period no longer than 4 weeks, each player underwent cardiopulmonary exercise testing in hospital.

Results

During Yo-Yo test, electrocardiogram (ECG) signal was interpretable in 16 players (84.2%). In the other three players, ECG artifacts did not allow a proper analysis. Estimation of maximum oxygen consumption was comparable between two exercise tests (VO₂ max 53.3 ± 2.4 vs. 53.7 ± 3.0 mL/kg/min for Yo-Yo test and ergometry respectively; intra-class correlation coefficient 0.84 (0.63 - 0.93), P < 0.001). No arrhythmias were detected in any player during both tests.

Conclusions

The use of Nuubo’s technology allows an accurate single-lead electrocardiographic recording and estimation of reliable performance variables during exercise testing in field, and provides a new perspective to cardiac remote monitoring in collective sports.

Predicted values of cardiopulmonary exercise testing in healthy individuals (a pilot study)

BACKGROUND

Cardiopulmonary exercise testing evaluates the ability of one's cardiovascular and respiratory system in maximal exercise. This was a descriptive cross-sectional pilot study conducted at Masih Daneshvari Hospital in order to determine predicted values of cardiopulmonary exercise testing in individuals with normal physical activity patterns.

MATERIALS AND METHODS

Thirty four individuals (14 women, 20 men) between 18-57 years of age were chosen using simple sampling method and evaluated with an incremental progressive cycle-ergometer test to a symptom-limited maximal tolerable work load. Subjects with a history of ischemic heart disease, pulmonary disease or neuromuscular disease were excluded from the study. Smokers were included but we made sure that all subjects had normal FEV1 and FEV1/FVC. This study aimed to compare measured values of VO2, VCO2, VO2/Kg, RER, O2pulse, HRR, HR, Load, Ant, BF, BR, VE, EQCO2, and EQO2 with previously published predicted values.

RESULTS

We found that our obtained values for VO2 max, HRR max and HR max were different from standard tables but such difference was not observed for other understudy variables. Multiple linear regression analysis was done for height, weight and age (due to the small number of samples, no difference was detected between males and females). VO2 max and load max had reverse correlation with age and direct correlation with weight and height (P < 0.05) but the greatest correlation was observed for height.

CONCLUSION

Due to the small number of samples and poor correlations it was not possible to do regression analysis for other variables. In the next study with a larger sample size predicted values for all variables will be calculated. If the future study also indicates a significant difference between the predicted values and the reference values, we will need standard tables made specifically for our own country, Iran.