Effect of 8 Weeks Endurance Training on Lipid Profile and Testosterone Levels in Young Judukas

Article history: Received on: 24/01/2015 Revised on: 11/03/2015 Accepted on: 05/05/2015 Available online: 27/06/2015 The present study examined the effects of endurance training on the lipid profile and testosterone levels in young male judokas. 18 judokas aged 18 to 21 years old participated in the study and were randomly divided into two groups: Exercise (n=9) and control group (n=9). The levels of LDL-C, HDL-C, TC, TG, and TT were measured in the blood samples of the subjects. No significant difference was detected in serum LDL-C in three stages of measurement (i.e. pre-, mid-, and post-test) (p=0.47); however, a significant difference was obtained in serum HDL-C during the three stages (p=0.03). There were no significant differences in serum TC (p=0.78) and TG (p=0.42). In Exercise group, TT levels was 18.98±12.45 in pre-test and it reached 20.56±5.76, but, it again reduced to 19.23±3.94 in Control group, TT levels was 18.76±6.98 in pre-test and it reached 20.35±14.87 while it dropped to 19.12±4.63. There were no significant difference between the stages in both groups (p>0.05).


INTRODUCTION
Obesity, high Density Lipoprotein Cholesterol (LDL-C) and Tri Acyl Glycerol (TAG) are risk factors for cardiovascular diseases (CVDs).Systematic physical activity causes many effects on the risk factors for cardiovascular disease.Reduction of Total Cholesterol (TC), TAG, and LDL-C and elevation of High Density Lipoprotein Cholesterol (HDL-C) have been observed during various exercise programs (Blessing et al., 1995;Durstine et al., 1994).However, some studies have shown no significant difference in lipid and lipoprotein concentrations (Ghahramanloo et al., 2009).Some studies showed that HDL-C increased during long-term endurance training in male (Marin et al., 1995;Thaveeratitham et al., 2007) and female (Lamon-Fava et al., 1989) triathlon and marathon athletes.On the contrary, short-term and <2-h trainings have shown uncertain results, because effective variables were not controlled in order to achieve more definitive results (Durstine et al., 1994).Studies also suggest that a lower concentration of TC and LDL-C along with high concentration of HDL-C reduces CVD risk (Grundy et al., 1997;Vega et al., 1997).HDL-C has antioxidant and antiinflammatory properties and improves vascular reactions; therefore, it plays a major role in immune system and against infection (Thaveeratitham et al., 2007).
In general, the higher concentration of triglyceride reduces concentration of HDL-C.Testosterone is one of the most important hormones in the body.It is an anabolic steroid (histogen) that stimulates protein synthesis.Testosterone can be found in two forms, i.e.Free Testosterone (FT) and Total Testosterone (TT); higher TT level provides a basis for high FT level.Some authors believe that acute endurance training is a powerful stimulator in order to increase concentrations of anabolic hormones in the circulation.
Authors have shown that acute strength training may increase testosterone level and muscle hypertrophy, while endurance training, especially long-term aerobic training, reduces plasma testosterone (Thompson et al., 1980).
Considering the importance of testosterone and lipid profile and lack of investigations on effect of different methods of training on these factors in judokas, thus the aim of the present study is to investigate effect of 8 weeks of endurance training on testosterone level and lipid profile in young male judokas.

Subjects
Eighteen judokas, aged 18-21 years voluntary participated in this study with a mutual printed participation agreement.They received medicine questionnaire and filled in their medicine and disease history.They were screened for not having any CVDs, hormonal disorders, injury, and drug and / or alcohol use history.They were not involved with tobacco/alcohol consumption neither treated with steroid drugs, nor planned with any special diets or regular exercise.After the investigation a written consent was obtained from subjects.The subjects were randomly divided into two groups: Exercise (n=9) and Control (n=9).Before and after 8 weeks of training period, blood sampling was taken from all the subjects to measure biochemistry, anthropometric characteristics.The study protocol was approved by the local ethical committee and conducted in accordance with the Helsinki Declaration (Hannula et al., 2014).The physical and general characteristics the subjects are shown in table 1.The Exercise group regularly performed judo training for 4 times a week while the control group hadn't any training activity.

Training protocol
Endurance training protocol for exercise group consisted of running on treadmill for 4 times a week during 8 weeks.Every training session was consisted of 7-10 min warm-up by a various stretching, limber, and jumping movements.They were asked to also run for 18 min in 65% HRmax in the first week which reached 28.30 min in 86% HRmax (1.30 min and 3% increase per week) (Table 2).At the end, the subjects performed slow running, stretching and limber through 7-10 min as cooling down movements.HRmax is estimated by the following formula: HR max = 220 -age (1)

Blood sampling
Blood samples of the subjects, followed by 12 hours of fasting in both pre-and post-test (48 h after the last session), from the left brachial vein, were collected.To separate plasma, the blood samples were centrifuged for 10 min at a speed of 2500 rpm after being cast into tubes containing EDTA.The separated plasma was poured into microtubes and frozen down to -80 ℃.Finally, LDL-C, HDL-C, TC, and TG levels were measured using Pars-Azmoon kits.Also Testosterone was measured by using A Total Testosterone ELISA Kit (Diagnostics Biochem Canada Inc., Ontario, Canada).

Statistical analysis
All data are expressed as mean ± and Standard Deviations (SD) and are analyzed using SPSS statistical program to calculate the means and SD of the values collected.The differences between two groups are examined by the analysis of variance between groups (ANOVA).Moreover, Kolmogorov-Smirnov Test (KS) was used for normalization of data.For P <0.05 is considered statistically significant in the interpretation of our results.

RESULTS
TC level experienced a same method in both groups.It was increased from pre-test to mid-test while it was reduced from mid-test to post-test.There was no significant difference between two study groups (p>0.05).TG level decreased from pre-test to mid-test in both groups and again increased in post-test; neither here the difference was significant (p>0.05).LDL-C level had no significant change and it only gradually increased in both groups from pre-test to post-test and there were no significant difference between three stages in both groups (p>0.05).However, a considerable difference was found in HDL levels between the stages in both groups (p<0.05)where it was 44.87±5.56 in pre-test and it reached 53.45±8.76 and it again reduced to 40.29±3.76 in exercise group; a same trend was detected in Control group as well with minor variations.In the exercise group, TT was 18.98±12.45in pre-test and it reached 20.56±5.76 in midtest but it again reduced to 19.23±3.94.In Control group, TT was 18.76±6.98 in pre-test and it reached 20.35±14.87 while it dropped to 19.12±4.63.Furthermore, no significant difference was detected between the stages in both groups (p>0.05).

DISCUSSION
The aim of the study was to determine the effects of eight weeks endurance training on the lipid profile and testosterone level of young male judokas.There was no significant difference in serum of LDL-C in three stages of measurement (i.e.pre-, mid-, and post-test) (p=0.47).However, a significant difference was found in serum of HDL-C during the three stages (p=0.03).Furthermore, there were no remarkable differences in TC (p=0.78) and TG (p=0.42)serum.This is in agreement with the results obtained by Gilliam et al. (1978) who observed considerable increase in HDL-C and with TC that remained unchanged [4].Higher HDL-C can be regarded as a preventive factor for CVDs as lower level of HDL-C and higher level of TC and LDL-C have been seen in cardiovascular patients.Halverstadt et al, found that endurance training reduced LDL-C levels but significantly increased HDL-C levels in older men and women with body fat phenotypes (Halverstadt et al., 2007).Abnormal blood lipids are an important cardiovascular health risk.Many evidences supports that physical activity and exercise have a positive influence on abnormal lipids and they are usually suggested as adjunctive interventions.Related studies to the effects of exercise on blood lipid levels are remarkable.Many studies have shown the effects of exercise with different intensities and durations on cholesterol.Exercise also effects on HDL-C maturation and composition.Positive effects of exercise are also seen in the blood triglycerides (TG), but little specific effect has been found on low-density (LDL-C) and (TC).Abundant evidence supports the benefits of exercise on levels of certain blood lipids (namely HDL-C and TG).Although standard management of abnormal blood lipids is drug therapy and diet, it seems prudent to combine the factors with aerobic exercise as an important component for a healthy lifestyle (Trejo-Gutierrez et al., 2007;Gorji et al., 2015).Marlin et al. have shown that vein lipid dropped in obese men under testosterone treatment (Marin et al., 2007).In contrast, Tan et al. reported that there is no correlation between low levels of testosterone and high level of cholesterol.Tan showed that testosterone might reduce HDL-C concentration (Tan et al., 1998).A lower level of testosterone affects the HDL-C and also shows a pathogenic influence on CAD development.Some studies suggest that majority of CVD patients had high levels of androgens and atherosclerosis (Rosano et al., 2007).Many studies have shown a positive relationship between testosterone and CAD (Vega et al., 1996).In conclusion, both endurance and strength trainings may be considered effective to increase HDL-C level which has an antagonistic effect on testosterone level of blood.This may be attributable to lower cardiovascular risk.

Table 1 :
physical characteristics of the subjects.

Table 3 :
Lipid profile in study and control groups.