Journal of Respiratory and CardioVascular Physical Therapy

Editorial

2020-11-17T17:33:23-03:00

CORRELATION BETWEEN MAXIMUM INSPIRATORY PRESSURE (MIP) AND PEAK OXYGEN UPTAKE (VO2 PEAK) IN FEMALE PROFESSIONAL SOCCER ATHLETES

2020-11-17T17:12:34-03:00

Background: Ventilatory muscle training (VMT) has been described as a strategy to improve ventilatory and peripheral muscle strength and endurance in athletes of different modalities. However, the mechanisms involved in this process are not fully known. Oxygen uptake (VO2) is the gold standard variable for assessing functional capacity. Oxygen (O2) to be consumed by the peripheral muscles must pass through the cardiorespiratory system. In this rationale, it seems logical that the stronger the inspiration muscles, the higher the VO2. This work has shown that this may not be as deterministic as it sounds. Objective: To evaluate the correlation between inspiratory muscle strength through maximum inspiratory pressure (MIP) and peak oxygen uptake (VO2 peak) in female professional soccer athletes. Study Design: Prospective and cross-sectional study. Methods: 16 professional soccer players, female and aged between 18 and 40 years (26 ± 4.3), underwent measurement of maximum inspiratory pressure (MIP -120.7 ± 16.9) and performed the cardiopulmonary exercise test (TECP) in a treadmill, where the ventilatory and metabolic variables were measured. One of them was the VO2 peak (44.30 ± 5.9). The volunteers were assessed on the same day and time as follows: (i) assessment of inspiratory muscle strength; and, (ii) incremental cardiopulmonary exercise test up to maximum tolerance. The data were analyzed using the SPSS® version 13.0 statistical program, and Pearson's correlation was made between MIP and VO2peak. Importance of the Study: This study can reveal what kind of correlation exists between these important markers, helping in the development of new strategies for improving performance in sport. Results: The volunteers presented a MIP of -120.7 ± 16.9, and in the TECP on a treadmill, they obtained a VO2peak of 44.30 ± 5.9. The statistical analysis showed an inverse association with r = -0.14 and p = 0.612 between MIP and VO2peak. Conclusion: There was an inversely proportional correlation between MIP and VO2peak; thus, this result leads us to believe that inspiratory muscle strength does not seem to influence VO2peak directly.

EVALUATION OF CHEST WALL KINEMATICS DURING REST AND RESPIRATORY MUSCLE ENDURANCE IN OBESE PATIENTS

2020-11-17T17:12:36-03:00

Background: Obesity may affect the respiratory system, causing changes in respiratory function and in the pulmonary volumes and flows. Objectives: To evaluate the influence of obesity in the movement of thoracoabdominal complex at rest and during maximal voluntary ventilation (MVV), and the contribution between the different compartments of this complex and the volume changes of chest wall between obese and non-obese patients. Materials and Methods: We studied 16 patients divided into two groups: the obese group (n = 8) and group non-obese (n = 8). The two groups were homogeneous in terms of spirometric characteristics (FVC mean: 4.97 ± 0.6 L - 92.91 ± 10.17% predicted, and 4.52 ± 0.6 L - 93.59 ± 8.05%), age 25.6 ± 5.0 and 26.8 ± 4.9 years, BMI 24.93 ± 3.0 and 39.18 ± 4.3 kg/m2 in non-obese and obese respectively. All subjects performed breathing calm and slow and maneuver MVV, during registration for optoelectronic plethysmography. Statistical analysis: we used the unpaired t test and Mann-Whitney. Results: Obese individuals had a lower percentage contribution of the rib cage abdominal (RCa) during breathing at rest and VVM. The variation of end expiratory (EELV) and end inspiratory (EILV) lung volumes were lower in obese subjects. It has been found asynchrony and higher distortion between compartments of thoracoabdominal complex in obese subjects when compared to non-obese. Conclusions: Central obesity impairs the ventilation lung, reducing to adaptation efforts and increasing the ventilatory work.

DETERMINATION OF THE VENTILATORY ANAEROBIC THRESHOLD BY THE RESPONSE OF THE CARDIAC FREQUENCY OF INDIVIDUALS WITH A RISK FACTOR FOR CARDIOVASCULAR DISEASES: COMPARISON WITH A VISUAL METHOD

2020-11-17T17:12:37-03:00

ABSTRACT

DETERMINATION OF THE VENTILATORY ANAEROBIC THRESHOLD BY THE RESPONSE OF THE CARDIAC FREQUENCY OF INDIVIDUALS WITH A RISK FACTOR FOR CARDIOVASCULAR DISEASES: COMPARISON WITH A VISUAL METHOD

Introduction: Cardiovascular diseases (CVD) are the leading cause of death worldwide. The sedentary lifestyle stands out as one of the main risk factors related to CVD. It is essential that a thorough evaluation is carried out in order to prescribe in a proper manner, respecting the biological individuality. Cardiopulmonary exercise test (CPT) is a useful tool in determining functional capacity. The ventilatory anaerobic threshold (AT) is shown as an important parameter for exercise prescription. The gold standard method for obtaining AT is visual analysis of the curves obtained from the ventilatory variables of the CPT. However, analysis of heart rate (HR) response appears as a promising strategy as a useful, simple and low-cost tool for determining AT. Objective: To evaluate the validity of the LAV determination through the HR response during the CPT. Methods: Men and women were recruited, aged over 18 years and who presented risk factors for CVD. All volunteers underwent a clinical evaluation and the CPT by means of an incremental power protocol (10W/min) until physical exhaustion. The AT was determined by the graphical visual method and by the heteroscedastic statistical model, where the variables time, power, HR and oxygen consumption (VO₂) were analyzed. Results: No significant differences were found in VO₂ (mL/ kg/min), VO₂ (L/min) and power (W) values, comparing the determined methods. In addition, for all variables, strong and strong correlations were found. Conclusion: The determination of LAV by the HR response proved to be an adequate model.

Editorial Team

2020-11-24T01:17:11-03:00