Obesity and the Role of Short Duration Submaximal Work on Cardiovascular and Cerebral Hemodynamics

Abstract

The objective of this study was to compare gas exchange, cardiac and cerebral hemodynamic responses between 10 non-obese and 10 obese men during submaximal work. With the increasing prevalence of obesity, there is a need to understand the impact of obesity on work-induced responses. Participants completed a step-wise incremental cycling until they reached 60% of their age-predicted maximum heart rate. Gas exchange, cardiac and pre-frontal cortex hemodynamic responses were simultaneously measured during rest, work, and recovery. The non-obese group reached ~43% of their predicted maximal aerobic capacity as compared to ~34% in the obese group, with the non-obese working at a relatively higher workload and for more duration than the obese. The obese had elevated baseline heart rate and reduced whole-body oxygen uptake per body weight at baseline and task termination. Other cardiac and cerebral responses, although increased from baseline, were similar between groups during submaximal effort. In the obese, during recovery oxygen uptake and heart-rate recovery were slowest; cardiac output and rate pressure product were greatest, and left ventricle ejection time was shortest. However, both groups exhibited similar cerebral hemodynamics during recovery. These finding imply that, irrespective of their low aerobic fitness, obesity does not impair myocardial performance and cerebrovascular function during graded submaximal work, however, recovery from a short duration of work was influenced by their fitness level. Since a majority of activities of daily living are performed at individual’s submaximal level, understanding influence of obesity on submaximal work is critical.

Cardiovascular and cerebral hemodynamics during exercise and recovery in obese individuals as a function of their fitness status

“…During exercise, cerebral oxygenation/perfusion was similar between the obese groups (OB, LF‐OB, HF‐OB) and AMHC for all intensities. Our results are in agreement with a previous study showing similar COP (measured by NIRS) during submaximal cycling exercise between young obese adults and nonobese controls (Cavuoto and Maikala ). Previous findings in healthy young adults demonstrated a higher a COP in the fittest subjects (Brugniaux et al.…”

“…Similarly, hematological factors and inter‐individual variability in NIRS could have also influenced our results in our obese subjects during recovery. Our results agree with previously studies reporting similar cerebral hemodynamics after exercise in obese subjects versus nonobese controls (Cavuoto and Maikala , ). Other studies have reported a reduced cerebral hemodynamics during recovery in cardiac patients (Koike et al.…”

“…Similarly to the cardiovascular function, very few studies are reported on the impact of obesity on cerebral hemodynamics during exercise and recovery, and none were performed in older obese adults. Conflicting results on cerebral hemodynamics during exercise were recently reported in young obese men versus AMHC (Cavuoto and Maikala , ). One study reported a similar cerebral oxygenation‐perfusion (measured by near‐infra red spectroscopy: NIRS) during submaximal cycling exercise in young obese men versus AMHC (Cavuoto and Maikala ), while the same authors showed a reduced cerebral oxygenation (measured by NIRS) during repetitive incremental lifting to exhaustion in a similar cohort (Cavuoto and Maikala ).…”

Desempenho Motor No Teste De Velocidade De Deslocamento Em Estudantes Do Segundo Ano Do Curso De Educação Física-Bacharelado

“…Ao final do estudo as mulheres com sobrepeso e as obesas apresentaram respostas ruins de FC e pior recuperação de FC pós exercício se comparadas com as eutróficas. Esses resultados corroboram com estudo deCavuoto et al (2016) que demonstram elevadas depois aplicaram o teste de caminhada com ritmo autoselecionado pela percepção de esforço dos indivíduos. Os resultados das velocidades dos testes de caminhada foram menores no grupo de obesos, mas as respostas de volume de oxigênio (VO 2 ) e FC não tiveram diferenças estatisticamente significativas comparadas com os grupos de peso normal e com sobrepeso que obtiveram maiores velocidades.O menor desempenho dos obesos na velocidade comparando com os outros gruposFaria et al (2014) submeteram adolescentes obesos e eutróficos, de ambos os sexos, a exercícios físicos submáximos, e encontraram maiores valores de pressão arterial diastólica e frequência cardíaca maiores nos grupos obesos durante o exercício, e altos valores de pressão arterial sistólica no grupo de meninos obesos.Desta forma, concluíram que os obesos apresentam baixa tolerância ao exercício físico.…”

Μελέτη της μεταβολής στην οξυγόνωση του μετωπιαίου λοβού του εγκεφάλου μετά από ήπιο σωματικό stress με τη μέθοδο της υπέρυθρης φασματοσκοπίας σε ασθενείς με σακχαρώδη διαβήτη της κύησης

“…Αντίθετα, άλλες μελέτες δεν έδειξαν διαφορές στην αιμοδυναμική απάντηση του εγκεφάλου μεταξύ των παχύσαρκων ασθενών και των μαρτύρων κατά τη διάρκεια μέγιστης ή υπομέγιστης άσκησης καθώς και κατά την περίοδο της ανάληψης [269,270].…”