Multifactorial Influences on Oxygen Consumption Recovery Post-high-Intensity Exercise in Adults: A Cross-Sectional Study

The intended aim of the study is  to assess differences in fitness profile, fatigability, VO2 recovery patterns, and sleep quality across body fat percentages and evaluate their predictive effect on VO2 recovery after exercise. 

Eighty healthy participants with mean age was 24.53 ± 5.78 years was included in this cross-sectional study. The participants were divided into two groups based on body fat percentage: normal fat (CON; n=40, (fat %: 22.86± 7.02) and high fat (HFG; n=40, fat% 37.47±4.81). Participants performed a graded exercise test on treadmill (modified bulk protocol).  VO_2peak and VO₂ recovery kinetics were assessed through gas exchange analysis. The measurement of the VO₂ recovery was calculated breath by breath during two period (T1; T2). The VO₂ recovery _T1 denotes half-time of the first 3 min of the passive recovery (6 min), whereases the VO2 recovery _T2 denotes the second half-time of the last 3 min.   The PSQI questionnaire was used to assess sleep efficiency, and the performance fatigability index during 10-minute walk test was used to assess fatigability. The study was approved by the University Institutional Review Board of Princess Nourah bin Abdulrahman University (log #24-0504). Analysis of covariance (ANCOVA) and forward multiple linear regression models were conducted to investigate the association between VO₂ recovery (the dependent variable) and the predictive factors (the independent variables). 

Participants in CON group had higher mean of VO_2peak than high fat percentage group (p=0.0003). The half times recovery (T1 and T2) demonstrated higher amount of VO₂ in the CON group compared to HFG group (p=0.0007), (p=0.0005), respectively. Those with HFG reported higher performance fatigability (p=0.01) and poorer sleep quality compared to CON group (p0.001). The multiple linear regression model indicated that higher recovery amount of VO2 was associated with fat percentage, VO2 peak and fatigability index and explain variance by 72% (F = 39.58, p  0.001). 

Findings of this study revealed that participants with higher fat percentages exhibited increased performance fatigability and reduced VO2 profile and reported poor sleep quality compared in normal group. The CPF, body fat, sleep quality, performance fatigability was found to be associated with VO2 recovery post-high-intensity exercise. The interplay between body fat, fatigability, sleep quality, and VO2 recovery highlights the need for a holistic approach to health management.

The study underscores the critical role of body fat, cardiopulmonary fitness, sleep, and fatigability in determining VO2 recovery and, by extension, cardiovascular health. This evidence supports the need for comprehensive, multi-faceted interventions in both clinical and community settings to mitigate cardiovascular risks.