Multifactorial Influences on Oxygen Consumption Recovery Post-High-Intensity Exercise in Adults: A Case-Control Study

Background and Objectives: Oxygen consumption (VO₂) recovery plays a critical role in reestablishing homeostasis within multiple physiological processes. This study aimed to assess the differences in the fitness profiles, fatigability, patterns of VO₂ recovery, and sleep quality among individuals with different body fat percentages. Thus, we evaluated the predictive effects of body fat percentage, CRF, fatigability, and sleep quality on VO₂ recovery patterns following exercise. Materials and Methods: Eighty healthy participants aged 18-52 years were included in this case-control study. The participants were divided into two groups based on body fat percentage: normal-fat (CON; n = 40) and high-fat (HFG; n = 40) groups. The PSQI questionnaire was used to assess sleep efficiency, and a 10 min walk test was performed to assess fatigability. Both groups underwent a symptom-limited treadmill exercise test to assess VO₂ using a modified bulk protocol, followed by 6 min of passive recovery. Results: The participants in the CON group had a higher mean VO₂ peak than those in the high-fat-percentage group (p = 0.0003). The half-time recovery (T1 and T2) demonstrated higher amounts of VO₂ in the CON group compared to the HFG group (p = 0.0007 and p = 0.0005), respectively. Those in the HFG reported greater performance fatigability (p = 0.01) and poorer sleep quality compared to the CON group (p < 0.001). The multiple linear regression model indicated that a higher recovery amount of VO₂ was associated with the fat percentage, VO₂ peak, and fatigability index and explained 72% of the variance (F = 39.58, p < 0.001). Conclusions: The findings of this study revealed that the participants with higher fat percentages exhibited increased performance fatigability and a reduced peak VO₂ and reported poor sleep quality compared to the normal group. CPF, body fat, and performance fatigability were associated with VO₂ recovery after high-intensity exercise. The interplay between body fat, fatigability, sleep quality, and VO₂ recovery highlights the need for a holistic approach to healthcare.