Banca de DEFESA: RENATA CARLOS FELIPE

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : RENATA CARLOS FELIPE
DATA : 20/11/2017
HORA: 13:30
LOCAL: AUDITÓRIO DO DEPTO DE FISIOTERAPIA
TÍTULO:

 

Analysis of oxygen uptake kinetics in obese and eutrophic women considering different ergometers and exercise intensities.

PALAVRAS-CHAVES:

obesity, oxygen uptake, kinetics, cpx test

PÁGINAS: 154
GRANDE ÁREA: Ciências da Saúde
ÁREA: Fisioterapia e Terapia Ocupacional
RESUMO:

 

 

 

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Contextualization: Evaluation of oxygen uptake (VO₂) kinetics can elucidate issues related to low physical fitness in obese patients. Most day-to-day and work activities are performed on sub-maximal exercise intensity, and require various energy transitions, going from a resting condition to a moderate or vigorous activity at short and repeated time, requiring metabolism of different energy substrates. The ability to deal with a rest-activity transition involves a high coordination between the cardiovascular, respiratory and neuromuscular systems. An examination of the oxygen kinetics provides an adequate approximation of the oxygen transport and utilization processes in the muscle. Thus, it was raised the questioning if there is a slowing in oxygen kinetics in obese individuals, considering that there are no published studies addressing the temporal behavior of VO₂ in obese adults. Objective: To analyze and compare the VO₂ kinetics in eutrophic and obese women in different ergometers and test intensities. Materials and Methods: Cross-sectional observational study where obese and eutrophic women were evaluated. Volunteer were submitted to  physical clinical evaluation, pulmonary function testing, sleep disturbance assessment (Epworth Scale, Stanford Sleepiness Scale, Stanford Snoring Scale), self-perceived fatigue sensation (Fatigue Severity Scale), manual dynamometer (Jamar® Dynamometer), evaluation of exercise capacity and VO₂ kinetics through the Cardiopulmonary Exercise Test (CPX) and Square-wave Exercise Test (SWET) on a treadmill or cycle ergometer, with measurements of breath-by-breathy gas expired by the Cortex Metamax 3B. Group distribution for ergometer was performed by randomization, and four groups were formed: eutrophic evaluated on treadmill (ET), eutrophic on cycle ergometer (EC), obese on treadmill (OT) and obese on cycle ergometer (OC). Results: 142 volunteers were evaluated, 100 obese and 42 eutrophic. Of this total, 72 volunteers did not meet the inclusion criteria, resulting in a final sample of 60 women (15 ET, 15 EC, 15 OT, 15 OC). The sample was homogeneous in terms of age, height, and pulmonary function. CPX was performed by all volunteers, with obese subjects presenting lower VO₂/Kg_Peak and HR_MAX in the two ergometers studies. Analysis of oxygen kinetics showed that there is no difference between groups of obese and eutrouphic in time constant(τ) in the tests with intensity below (ET=42,7s, EC=36,4s, OT=37,6s, OC=34,1s, p>0,05) and above (ET=41,8s, OT=55,8s, p>0,05) the gas exchange threshold (GET). The slow oxygen component (VO_2SL) was higher to obese group evaluated on treadmill compared to eutrophics (ET=0,162L/min, OT=0,283L/min, p<0,05). Conclusion: Our findings suggest that there is no limitation on transport of O₂ during exercise with intensity below GET. However, the increase in VO_2SL amplitude in OT, suggests a greater metabolic inefficiency in adjusting oxidative metabolism to energy demand in exercise supra-GET, which may be related to low exercise tolerance. Thus, we suggest that exercise prescription must be done considering GET, not VO_2MAX, prioritizing endurance training in rehabilitation programs and physical training, aiming to improve the exercise capacity of the obese.

MEMBROS DA BANCA:
Externo à Instituição - DANIELLA CUNHA BRANDÃO - UFPE
Externo ao Programa - 2419223 - GERSON FONSECA DE SOUZA
Externo à Instituição - MICHEL SILVA REIS - UFRJ
Presidente - 1149619 - SELMA SOUSA BRUNO
Interno - 5566309 - VANESSA REGIANE RESQUETI FREGONEZI