Effect of Continuous-Exercise and Modification Interval-Exercise on Decreasing Malondialdehyde and Blood Lactate Levels in Non-Professional Shorinji Kempo Athletes

The study purpose was to analyze the effect of continuous exercise and modification interval exercise on decreasing malondialdehyde (MDA) and blood lactate levels in non-professional Shorinji Kempo athletes. Materials and methods. This study used a quasi-experimental method with a randomized pretest posttest-only group design. Subjects were 16 male adolescents aged 18-20, body mass index (BMI) 20-24 kg/m2, who had normal blood pressure, normal resting heart rate, and no history of chronic disease. The subjects were randomly divided into two groups: CEG (n = 8, continuous exercise group) and MIEG (n = 8, modification interval exercise group). Continuous and modification interval exercises were carried out in 30 minutes/exercise sessions, with an intensity of 75% HRmax and 75% RM, as often as 3 times/week, for one week. Measurements of resting heart rate, blood lactate and MDA levels were performed 30 minutes pre-exercise and 10 minutes post-exercise. The data analysis technique used the Paired Sample T-Test and the independent T-test with SPSS software version 21. Results. The results showed significant differences in resting heart rate, blood lactate and MDA levels pre-exercise vs. post-exercise on CEG and MIEG (p ≤ 0.05). A difference was also observed in Delta (Δ) heart rate pre-exercise vs. post-exercise on CEG (–3.88 ± 3.36 bpm) and MIEG (–15.25 ± 3.45 bpm) (p ≤ 0.001), but no differences were observed in the Delta (Δ) blood lactate and MDA levels in both groups. Conclusion. Based on the study results, it was shown that continuous exercise and modification interval exercise increase blood lactate and MDA levels shortly after intervention but both exercises could reduce acute stress, which was indicated by a decrease in resting heart rate.