beneficial mitochondrial biogenesis in gastrocnemius muscle promoted by high-intensity interval training in elderly female rats

Objective: exercise can attenuate mitochondrial dysfunction caused by aging. our study aimed to compare 12weeks of high-intensity interval training (hiit) and moderate-intensity continuous training (mict) on the expressionof mitochondria proteins [e.g., amp-activated protein kinase (ampk), estrogen-related receptor alpha (errα), p38mitogen-activated protein kinase (p38mapk), and peroxisome proliferator-activated receptor gamma coactivator1-alpha (pgc1-α)] in gastrocnemius muscle of old female rats.materials and methods:in this experimental study, thirty six old female wistar rats (18-month-old and 270-310 g) weredivided into three groups: i. hiit, ii. mict, and iii. control group (c). the hiit protocol was performed for 12 weeks with16-28 minutes (2 minutes training with 85-90% vo2max in high intensity and 2 minutes training with 45-75% vo2max low intensity). the mict was performed for 30-60 minutes with the intensity of 65-70% vo2max. the gastrocnemius muscle expression of ampk, errα, p38mapk, and pgc1α proteins were determined by western blotting.results:the expression of ampk (p=0.004), p38mapk (p=0.003), pgc-1α (p=0.028), and errα (p=0.006) in hiitwas higher than c group. ampk (p=0.03), p38mapk (p=0.032), pgc-1α (p=0.015), and errα (p=0.028) in mictwas higher than the c group. also expression of ampk (p=0.008), p38mapk (p=0.009), pgc-1α (p=0.020) and errα(p=0.014) in mict was higher than mict group.conclusion:it seems that exercise training has beneficial effects on mitochondrial biogenesis, but the hiit trainingmethod is more effective than mict in improving mitochondrial function in aging.