Time-dependent cortical plasticity during moderate-intensity continuous training versus high-intensity interval...

Area of Science:

• Neuroscience
• Exercise Physiology
• Neuroplasticity

Background:

• Cortical plasticity is crucial for preventing neurological disorders.
• Understanding the temporal effects of different exercise intensities is needed.

Purpose of the Study:

• To define the time-dependent effects of work-matched high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on cortical plasticity, endurance, and sensorimotor performance.
• To investigate changes in neurotrophic, angiogenic, and metabolic markers over an 8-week period in rats.

Main Methods:

• Adult rats underwent incremental exercise and sensorimotor tests before and at 2, 4, and 8 weeks of training.
• Cortical tissue was analyzed for neurotrophic, angiogenic, and metabolic markers.

Main Results:

• HIIT led to earlier and greater improvements in endurance, speed associated with lactate threshold (SLT), and maximal speed (Smax) compared to MICT.
• MICT initially increased brain-derived neurotrophic factor and angiogenic/metabolic markers, but effects diminished by 8 weeks.
• HIIT upregulated insulin-like growth factor-1 (IGF-1) and other markers at 2 and 8 weeks, while downregulating KCC2.

Conclusions:

• Both HIIT and MICT are effective in a time-dependent manner for improving physical and neural parameters.
• HIIT demonstrates superior and sustained effects on endurance and specific neurotrophic markers.
• Exercise guidelines may benefit from incorporating complementary HIIT and MICT strategies for optimal brain health.