Wantang Su ¹ Jianming Liu ^2,3 Aozhe Wang ¹ Haifeng Zhang ⁴ Yaqi Sun ¹ Zhiyi Yan ¹ Michael Svensson ⁵ Ji-Guo Yu ^5* Li Zhao ^1*

• ¹ Department of Exercise Physiology, Beijing Sport University, Beijing, China
• ² School of Physical Education and Sports Science, Qufu Normal University, Qufu, China
• ³ School of Competitive Sports, Beijing Sport University, Beijing, Beijing Municipality, China
• ⁴ Beijing Municipal Key Laboratory of Child Development and Nutriomics, Capital Institute of Pediatrics, Beijing, China
• ⁵ Department of Community Medicine and Rehabilitation, Section of Sports Medicine, Umeå University, Umeå, Sweden

Background: Exercise-induced metabolic changes, especially lipidomic changes are generally associated with improvements in cardiovascular health. Despite numerous previous studies, the differences in lipidomic profile response to different types of exercise training remain unclear. This study aimed to investigate how two different exercise intensities affect aerobic capacity and serum lipidomic profiles in healthy adolescents.Methods: Twenty-four healthy untrained male adolescents (13.08 ± 0.88 years) were recruited and randomly assigned to moderate intensity continuous training (MICT) group and sprint interval training (SIT) group to complete a specific training on a cycle ergometer for 6 weeks. Peak oxygen uptake (VO2peak) and body composition were measured, and blood samples were collected for serum lipoproteins and lipidomic analysis. Anthropometric, VO2peak, and serum biochemical data were analyzed using two-way repeated analysis of variance, while targeted lipidomic analysis was performed by principal component analysis and paired-sample t test.Results: VO2peak significantly improved from 39.05 ± 8.17 to 47.52 ± 8.51 [F (1, 44) = 14.75, p < 0.05] for MICT and from 40.13 ± 6.37 to 48.42 ± 7.01 [F (1, 44) = 14.75, p < 0.05] for SIT. A total of 28 lipids in MICT and 5 lipids in SIT showed significant changes out of 276 identified lipids (FC >1.5 or < 1/1.5, FDR < 0.05). In MICT, 21 lipids, including sphingolipid (SP) and phospholipid (PL), decreased, while 7 lipids increased. In SIT, all 5 lipids, which were free fatty acid (FFA), decreased. Conclusion: Although both MICT and SIT induced similar and significant improvements in VO2peak, serum lipid adaptations to the training differed. The primary changes in serum lipidomic intermediates for both types of training were reductions; however, SIT affected FFA, while MICT predominantly influenced SPs and PLs.