Ventilatory and Metabolic Response in the Incremental Shuttle and 6-Min Walking Tests Measured by Telemetry in Obese Patients Prior to Bariatric Surgery

Comparison of physiological responses after incremental shuttle walking test and 6-minute walk test in patients with systemic sclerosis

BACKGROUND

The 6‑minute walk test (6MWT) is a commonly used to evaluate exercise capacity in patients with systemic sclerosis (SSc), but there was no study using the incremental shuttle walking test (ISWT) for assessing exercise capacity and comparing the patient's cardiorespiratory responses to these tests. The aim was to investigate the usability and determinants of the ISWT in patients with SSc and compare the physiological responses after the ISWT and 6MWT.

METHODS

A total of thirty four female patients with SSc were included. Dyspnea during daily activities and knee extensor muscle strength was assessed, skin fibrosis and disease severity were recorded, and 6MWT and ISWT were carried out for the exercise capacity measurement. Pulmonary function test results were recorded from the individuals' medical records for SSc with interstitial lung disease (SSc-ILD) patients.

RESULTS

The ISWT distance was significantly correlated with the 6MWT distance (p < 0.001). The 6MWT was correlated with age, modified Rodnan skin score, Medsger severity score, modified British Medical Research Council Questionnaire (mMRC) score, and knee extensor muscle strength (p < 0.05). The 6MWT was correlated with the forced expiratory volume in the first second (FEV1) (lt) and forced vital capacity (FVC) (lt) in patients with SSc-ILD (p < 0.05). The ISWT distance was correlated with age, modified Rodnan skin score, mMRC score, and knee extensor muscle strength (p < 0.05). Age, mMRC, and knee extensor muscle strength explained 33.8% of the variance in 6MWT distance, while age, mMRC, and knee extensor muscle strength explained 51.7% of the variance in the ISWT distance.

CONCLUSION

Because of the higher cardiopulmonary responses, and having a more standardized procedure, the ISWT may be preferable for investigating symptom-limited exercise capacity in patients with SSc. Age, dyspnea, and knee extensor muscle strength were the determinants of exercise capacity in patients with SSc.

SIMULATION OF THE RELATIONSHIP BETWEEN EXERCISE AND CARDIOPULMONARY FUNCTION AT HIGH ALTITUDE

ABSTRACT Introduction: Due to various uncertain and unexpected factors in life such as diseases, natural disasters, traffic accidents, and congenital disabilities, the number and proportion of lower limb amputations are still rising for many reasons, so the research on lower limb prostheses is particularly important. Objective: This work aimed to study the relationship between altitude exercise and cardiopulmonary function. Methods: A model of abnormal changes in cardiopulmonary function was established, and then 40 plateau exercisers were selected, all of whom arrived in Tibet in March 2017. The relationship between pulmonary circulation volume and internal pressure in the chest was observed and compared. The relationship between cardiopulmonary sensory reflex and exercise (high altitude) breathing and heart rate was analyzed. A comparison of the cardiopulmonary function of subjects of different genders was implemented. Moreover, the influence of different altitudes on the subjects’ cardiopulmonary function and the subjects’ cardiopulmonary function changes before departure and during the first, second, and third week after departure were observed and compared. Results: I. As the pressure in the thoracic cavity increased, the subjects’ pulmonary circulation blood volume gradually decreased, and the decrease was most obvious in the stage of thoracic pressure −50 to 0. II. As the cardiorespiratory reflex coefficient increased, the subjects’ breathing and heart rate compensatory acceleration appeared. III. Tracking and monitoring of the subjects’ cardiopulmonary indicators revealed that with the increase in altitude, the subjects’ average arterial pressure, respiratory frequency, and heart rate all showed an upward trend, while the blood oxygen saturation value showed a downward trend. IV. No matter how high the altitude was, the average arterial pressure, respiratory rate, and heart rate monitored of the subjects under exercise were significantly superior to the indicator values under resting state. In contrast, the blood oxygen saturation value showed the opposite trend. V. The subjects’ average arterial pressure, respiration, and heart rate in the first week were higher than other periods, but the blood oxygen saturation was relatively lower. In the second and third weeks, the changes in cardiopulmonary function were relatively smooth (all P<0.05). VI. The changes in the index of the cardiopulmonary function of subjects of different genders were small (p>0.05). Conclusion: Through modeling, the results of the plateau environment on the cardiopulmonary function of the body were made clearer, and these research data provided theoretical references for the training of the sports field in the plateau area. Level of evidence II; Therapeutic studies - investigation of treatment results.

Comparação das respostas fisiológicas do incremental shuttle walk test e do Glittre-ADL test: instrumentos complementares para avaliação da capacidade funcional

RESUMO O objetivo deste estudo foi avaliar e comparar respostas metabólicas, cardiovasculares e ventilatórias do incremental shuttle walk test (ISWT) e do Glittre activities of daily living test (Glittre-ADL test). Trata-se de um estudo transversal, realizado com indivíduos saudáveis. A capacidade funcional (CF) foi avaliada pela distância percorrida e consumo de oxigênio pico (VO2pico) no ISWT e pelo tempo gasto e VO2 no Glittre-ADL test. Trinta indivíduos percorreram 656,67 (IC95%:608,8-704,5) metros no ISWT e executaram o Glittre-ADL test em 2,4 (IC95%:2,2-2,6) minutos. O VO2 pico do ISWT foi 27,8 (IC95%25,6-29,9) versus 22,2 (IC95%20,5-24,1)mL×kg−1×min−1 (p<0,001) no estado estável (EE) do Glittre-ADL test. As correlações entre distância percorrida no ISWT e o tempo gasto no Glittre-ADL test, o VO2pico do ISWT e o VO2 no EE do Glittre-ADL test e a FC no pico do ISWT e no EE do Glittre-ADL test foram de moderada a alta magnitude. O Glittre-ADL test apresenta menores respostas metabólicas, cardiovasculares e ventilatórias se comparado ao ISWT.

Evaluation of exercise capacity using two field tests in patients with metabolic syndrome

PURPOSE

Field tests are popular for assessing exercise capacity because they are practical and have established validity. The objective of this study was to compare physiological responses and exercise performance of patients with metabolic syndrome in two field tests of exercise capacity.

MATERIAL AND METHODS

Forty-seven patients diagnosed with metabolic syndrome participated in this cross-sectional study. Exercise capacity was assessed using incremental shuttle walk test and six-minute walk test. Factors determining exercise capacity and agreement between the two tests were also investigated.

RESULTS

Metabolic syndrome patients achieved a significantly greater percentage of predicted maximal heart rate, blood pressure, and longer distance in the incremental shuttle walk test than in the six-minute walk test (p < 0.001). Gender and body mass index explained 48.5% of the variance in six-minute walk test distance (R = 0.697, R² = 0.485, F_(2-46) = 20.737, p < 0.001). Body mass index and fat-free mass explained 55% of the variance in incremental shuttle walk test distance (R = 0.746, R²= 0.557, F_(2-46) = 27.623, p < 0.001).

CONCLUSIONS

Despite the agreement in the percentages of predicted maximal heart rate during these two field tests, the incremental shuttle walk test may be a better assessment tool than the six-minute walk test because it elicits more pronounced and definitive physiological responses to exercise tolerance in patients with metabolic syndrome.IMPLICATIONS FOR REHABILITATIONThe incremental shuttle walk test can be used to evaluate exercise capacity in metabolic syndrome.The incremental shuttle walk test elicits greater physiological responses than the six-minute walk test.The incremental shuttle walk test may be preferable over the six-minute walk test in investigating exercise capacity.Both tests can guide and assist in the evaluation of this patient population in clinical practice.Body mass index affected distance in both exercise tests.

The effects of a pilates-aerobic program on maximum exercise capacity of adult women

ABSTRACT Introduction: Physical exercise such as the Pilates method offers clinical benefits on the aging process. Likewise, physiologic parameters may be improved through aerobic exercise. Methods: In order to compare the differences of a Pilates-Aerobic intervention program on physiologic parameters such as the maximum heart rate (HRmax), relative maximal oxygen consumption (relative VO2max) and absolute (absolute VOmax), maximum heart rate during maximal oxygen consumption (VO2max-HRmax), maximum minute volume (VE) and forced vital capacity (FVC), a total of 64 adult women (active group = 48.1 ± 6.7 years; control group = 47.2 ± 7.4 years) participated in the study. The physiological parameters, the maximal speed and total duration of test were measured by maximum exercise capacity testing through Bruce protocol. The HRmax was calculated by a cardio-ergometric software. Pulmonary function tests, maximal speed and total time during the physical test were performed in a treadmill (Medisoft, model 870c). Likewise, the spirometry analyzed the impact on oxygen uptake parameters, including FVC and VE. Results: The VO2max (relative and absolute), VE (all, P<0.001), VO2max-HRmax (P<0.05) and maximal speed of treadmill test (P<0.001) showed significant difference in the active group after a physical exercise interventional program. Conclusion: The present study indicates that the Pilates exercises through a continuous training program might significantly improve the cardiovascular system. Hence, mixing strength and aerobic exercises into a training program is considered the optimal mechanism for healthy aging.

Oxygen uptake efficiency slope as a useful measure of cardiorespiratory fitness in morbidly obese women

Cardiopulmonary assessment through oxygen uptake efficiency slope (OUES) data has shown encouraging results, revealing that we can obtain important clinical information about functional status. Until now, the use of OUES has not been established as a measure of cardiorespiratory capacity in an obese adult population, only in cardiac and pulmonary diseases or pediatric patients. The aim of this study was to characterize submaximal and maximal levels of OUES in a sample of morbidly obese women and analyze its relationship with traditional measures of cardiorespiratory fitness, anthropometry and pulmonary function. Thirty-three morbidly obese women (age 39.1 ± 9.2 years) performed Cardiopulmonary Exercise Testing (CPX) on a treadmill using the ramp protocol. In addition, anthropometric measurements and pulmonary function were also evaluated. Maximal and submaximal OUES were measured, being calculated from data obtained in the first 50% (OUES_50%) and 75% (OUES_75%) of total CPX duration. In one-way ANOVA analysis, OUES did not significantly differ between the three different exercise intensities, as observed through a Bland-Altman concordance of 58.9 mL/min/log(L/min) between OUES_75% and OUES_100%, and 0.49 mL/kg/min/log(l/min) between OUES/kg_75% and OUES/kg_100%. A strong positive correlation between the maximal (r = 0.79) and submaximal (r = 0.81) OUES/kg with oxygen consumption at peak exercise (VO_2peak) and ventilatory anaerobic threshold (VO_2VAT) was observed, and a moderate negative correlation with hip circumference (r = -0.46) and body adiposity index (r = -0.50) was also verified. There was no significant difference between maximal and submaximal OUES, showing strong correlations with each other and oxygen consumption (peak and VAT). These results indicate that OUES can be a useful parameter which could be used as a cardiopulmonary fitness index in subjects with severe limitations to perform CPX, as for morbidly obese women.

Preoperative 6-minute walk distance accurately predicts postoperative complications after operations for hepato-pancreato-biliary cancer

BACKGROUND

Operation for hepato-pancreato-biliary cancer is among the most invasive open abdominal operations, with a high postoperative morbidity and mortality rate. The purpose of the present study is to investigate whether a preoperative 6-minute walk distance can predict major postoperative complications after operation for hepato-pancreato-biliary diseases.

METHODS

A total of 81 participants who underwent pancreaticoduodenectomy, major hepatectomy with extrahepatic bile duct resection, or hepatopancreatoduodenectomy were included. The 6-minute walk distance was performed within 1 week before operation. Patients were categorized into 2 groups based on surgical complications: Clavien-Dindo grade <3 and Clavien-Dindo grade ≥3. Clinical differences between the 2 groups were analyzed. Multivariate logistic regression analysis was performed to identify risk factors for postoperative complications that were categorized as Clavien-Dindo grade ≥3.

RESULTS

The multiple logistic regression model revealed a significant correlation between major postoperative complications and preoperative low 6-minute walk distance, low body mass index, and major blood loss. In patients with 6-minute walk distance <400 m (1,312 feet), the Clavien-Dindo grade was considerably greater than patients with ≥400 m.

CONCLUSION

The 6-minute walk distance is useful in identifying patients with a greater chance of developing major postoperative complications after surgery for hepato-pancreato-biliary cancer.

Does the incremental shuttle walk test require maximal effort in young obese women?

Obesity is a chronic disease with a multifaceted treatment approach that includes nutritional counseling, structured exercise training, and increased daily physical activity. Increased body mass elicits higher cardiovascular, ventilatory and metabolic demands to varying degrees during exercise. With functional capacity assessment, this variability can be evaluated so individualized guidance for exercise training and daily physical activity can be provided. The aim of the present study was to compare cardiovascular, ventilatory and metabolic responses obtained during a symptom-limited cardiopulmonary exercise test (CPX) on a treadmill to responses obtained by the incremental shuttle walk test (ISWT) in obese women and to propose a peak oxygen consumption (VO2) prediction equation through variables obtained during the ISWT. Forty obese women (BMI ≥30 kg/m2) performed one treadmill CPX and two ISWTs. Heart rate (HR), arterial blood pressure (ABP) and perceived exertion by the Borg scale were measured at rest, during each stage of the exercise protocol, and throughout the recovery period. The predicted maximal heart rate (HRmax) was calculated (210 - age in years) (16) and compared to the HR response during the CPX. Peak VO2 obtained during CPX correlated significantly (P<0.05) with ISWT peak VO2 (r=0.79) as well as ISWT distance (r=0.65). The predictive model for CPX peak VO2, using age and ISWT distance explained 67% of the variability. The current study indicates the ISWT may be used to predict aerobic capacity in obese women when CPX is not a viable option.