Dynamic Metabolic Changes Driven by Exercise Intensity in Acute Swimming

Utilizing wearable devices and high-throughput omics technologies, the study aimed to establish an intensity-specific human acute swimming exercise model and draw a swimming metabolome atlas to clarify the commonalities and specificities in a panoramic dynamic physiological response under different intensities.

Forty-two healthy nonathlete young adults were randomly divided into moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) acute swimming groups. Blood samples were collected at baseline, 0, 15 and 30 min after swimming for metabolomics and targeted lipidomics testing.

1) Baseline results showed high homogeneity among participants. There were no statistical differences in total exercise duration or energy expenditure between groups ( P > 0.05), but HIIT showed significantly higher average speeds and maximum heart rates than MICT ( P < 0.001). 2) Two hundred nine metabolites (56.5%) following swimming exercise significantly changed ( P < 0.05), whereas five metabolites were identified by their significant intensity-dependent characteristics, and Pearson correlation analysis revealed the strongest correlation ( r = 0.917) between levels of N -acetylvaline and lactic acid. 3) Combining longitudinal sampling with omics temporal dynamic analysis, acute swimming atlas showed MICT and HIIT significantly upregulated the tricarboxylic acid cycle and presented commonalities and intensity differences in amino acids metabolism related to the emotional regulation pathway and lipid metabolism related to fat hydrolysis and oxidative utilization.

The study established an intensity-specific human acute swimming model. N -Acetylvaline may be a potential novel intensity-specific exercise biomarker. The acute swimming metabolome atlas reveals substrate utilization and recovery characteristics driven by intensities, especially for emotional regulation pathway and lipid metabolism.