Acute Effects of Serial and Integrated Concurrent Exercise on Circulating microRNAs -126 and -222 in Sedentary Adults

Area of Science:

• Exercise Physiology
• Molecular Biology
• Biomarkers

Background:

• Circulating microRNAs (c-miRs) are emerging biomarkers influenced by physical activity.
• Understanding how different concurrent exercise structures affect c-miRs is crucial for exercise prescription.
• Previous research has not directly compared serial concurrent exercise (SCE) and integrated concurrent exercise (ICE) regarding c-miR responses.

Purpose of the Study:

• To compare the acute effects of SCE and ICE on circulating microRNAs -126 (c-miR-126) and -222 (c-miR-222).
• To investigate these effects in young, sedentary adults.

Main Methods:

• Nineteen healthy young adults (10 males, 9 females) participated.
• Participants underwent two exercise sessions: SCE (resistance exercise followed by aerobic exercise) and ICE (aerobic exercise interspersed with resistance exercise).
• Blood samples were collected pre-exercise, immediately post-exercise (IP), and 1 hour post-exercise (1HR) to measure c-miR expression.

Main Results:

• Both SCE and ICE significantly increased c-miR-126 expression at IP and 1HR compared to baseline.
• Both SCE and ICE significantly increased c-miR-222 expression at IP and 1HR compared to baseline.
• No significant differences in c-miR-126 or c-miR-222 responses were observed between the SCE and ICE protocols.

Conclusions:

• Both SCE and ICE protocols are equally effective in acutely increasing circulating miR-126 and miR-222 levels.
• These findings suggest that exercise sequencing in concurrent training does not differentially impact these specific microRNA responses in the short term.
• This provides valuable insights for optimizing concurrent exercise strategies for potential health benefits mediated by microRNAs.