Cardio skeletal muscle stress markers responses against two different intensity endurance training zones in novice athletes

Abstract

This study aimed to investigate the effects of two different intensity endurance training zones on cardio skeletal stress markers in search of optimum training intensity. In this study, a completely randomized parallel-group study design was employed. Thirty healthy male young athletes aged between 18-25 years old were selected and randomly assigned to two intensity endurance exercise groups. Pre-training at the end of 1 week and 12-week endurance training cardio skeletal muscle stress markers were assessed for both intensity groups. The first group trained at 60-70% maximum heart rate of 45 min per session for the first week and 3-minute increments each week from the second to 12^th weeks. The second intensity training was done at 70-80% maximum heart rate 30 min per session for the first week and 2-minute increments each week and ANOVA to analyze the data. There was a significant difference between pre to 1 and 12-week post-training tests of LDH (p < .001), CTnI (p < .001), and Ckmb (p <.001) with medium effect size in all cardio skeletal muscle stress markers for both intensity zones. Our findings confirmed that endurance training at both intensities with gradual increments in training duration reduces exercise-induced cardio skeletal muscle stress markers. However, the reduction rate is less in 70-80% HRmax intensity level than in 60-70% HRmax indicating changes in cardio skeletal muscle stress markers are not easily adaptable in higher intensities.