Background & Objectives: It is well established that High-intensity Interval Training (HIT) may represent a time-efficient strategy to induce adaptations normally associated with endurance training. However, the effect of exercise on lung mitochondrial changes is not well understood.The purpose of the present study is to determine the effects of HIT on NRF-1 and PGC-1α genes at mRNA level in rat lung tissue.

Materials & Methods: Twenty Wistar male rats (4 weeks old, 68±9 g weight) were randomly assigned to 6-week training, 9-week training, 6-week control and 9-week control groups. High-intensity interval training program was started with 25 m/min and gradually reached to 70 m/min at the end of the ninth week. Following tissue sampling, RNA extraction and cDNA synthesis, and the expressions of genes were determined by real time RT-PCR technique.

Results: NRF-1 and PGC-1α genes expression were increased following interval training. The expression of NRF-1 and PGC-1α between 9-week training and 9-week control groups was significantly different (P≤0.05).

Conclusion: According to the current study, it seems that intense interval training can cause changes in the mitochondrial content and the possibly of mitochondrial biogenesis in lung tissue.