EFFECT OF GIVING BEETROOT JUICE DURING SUBMAXIMAL EXERCISE AGAINST MUSCLE DAMAGE

Strenuous physical activity causes muscle damage marked by an increase in C-reactive protein (CRP) concentrations. Muscle damage caused by physical activity can be prevented or reduced by giving antioxidants and anti-inflammatory. It is known that beetroot (Beta Vulgaris L) has antioxidant and anti-inflammatory effects. The purpose of this study was to determine the effect of giving beet juice during submaximal exercise on concentrations of C - reactive protein (CRP). This type of research is an experimental study with a randomized control group pretest-posttest design. The research was conducted at the physiology laboratory of Departement of Sports Science Faculty Universitas Negeri Medan and the integrated Laboratory of the Faculty of Medicine at University of Sumatera Utara. The study used 20 futsal athletes who met the criteria. Furthermore, the sample was divided into 2 groups (experiment = 10, control = 10). The pre-test was done by checking the CRP concentrations prior to submaximal physical exercise. During one month of sub-maximal exercise program with a frequency of 3 times a week with an intensity of 80-90%, the experimental group was given 300 ml of beetroot juice one hour before submaximal exercise, while the control group was given a placebo drink. Measurement of research variables was carried out again immediately after submaximal exercise for one month. The results showed that beetroot juice supplementation at a dose of 300 ml/day in submaximal exercise significantly reduced CRP levels compared to the control group (18.00 ± 5.65 mg/L VS 74.66 ± 23.85 mg/L; p = 0.000). In conclusion, giving beetroot juice during training for one month can reduce the CRP levels that are increased in submaximal physical exercise in athletes. The decrease in CRP levels is due to the antioxidant content found in beetroot juice.