Study On Application Of Urine And Serum Steroid Metabolites For Training Load Monitoring Of Wrestlers

Objective:Training load monitoring is an important support for the scientific training and meticulous protection in the preparation for the Olympic Games.The amount and frequency of venous blood sampling are important limiting factors for training load monitoring.This paper aims to analyse the characteristics of steroid（hormone）metabolites in urine and blood and their correlation with blood biochemical indicators commonly used by national teams in preparation for the Olympic Games through targeted metabolomics,with a view to discovering high-throughput or non-invasive indicators for effective monitoring of athletes’ training load.Methods:Ten outstanding athletes from each of the national men’s classical and women’s wrestling teams preparing for the Tokyo 2020 Olympic Games were selected for the study.Among them,there were 6 men’s international athletes and 4 athletic athletes,2of whom participated in the Tokyo Olympics and 1 won a bronze medal;9 women’s international athletes and 1 athletic athlete,6 of whom participated in the Tokyo Olympics and won 2 silver and 1 bronze medal.Fasting blood and urine were also collected on Monday mornings during the loading and adjustment weeks of the training period from 2 November 2020 to 26 July 2021 to test 20 steroid（hormone）metabolites for targeted metabolomics in addition to the biochemical indicators commonly used by national teams for training load monitoring（testosterone,cortisol,creatine kinase,blood urea,haemoglobin）,where the final urine concentration of each metabolite Urine creatinine was used for correction.A total of 386 valid urine samples（161 men and 225 women）and 290 blood samples（132 men and 158 women）were obtained.Multivariate statistical analysis of the metabolomics data was performed using SIMCA 14.1 software.T-test or ANOVA combined with multivariate statistical analysis of VIP results were used to screen for differential metabolites（screening criteria were VIP>1 and P<0.05）.The screened differential metabolites were imported into the Metabo Analyst 5.0 platform KEGG database for metabolic pathway analysis to obtain the metabolic pathways involved in the differential metabolites.The blood and urine steroid metabolites were compared with the common biochemical load monitoring indicators of the national team separately to analyse whether there was a co-variation relationship between the two.Results:（1）Urinary metabolite profile: cortisol（VIP=1.79,P<0.01）,adrenocorticosterone（VIP=2.36,P<0.01）and dehydroisandrosterone sulfate（VIP=1.52,P<0.01）in male athletes;dihydrotestosterone（VIP=2.17,P<0.01）,dehydroisandrosterone sulfate（VIP=1.90,P<0.01）,aldosterone（VIP=1.61,P<0.01）,and androstenedione（VIP=1.13,P<0.01）in female athletes.1.90,P<0.01),aldosterone（VIP=1.61,P<0.01）,androstenedione（VIP=1.13,P<0.01）and adrenocorticosterone（VIP=1.08,P<0.01）were the differential metabolites at the loading and adjustment weeks in female athletes.（2）Serum metabolite profile: cortisol（VIP=2.95,P<0.01）,corticosterone（VIP=2.18,P<0.01）and dehydrotestosterone sulfate（VIP=1.58,P<0.01）in male athletes,androstenedione（VIP=1.58,P<0.01）,testosterone（VIP=1.48,P<0.01）,dehydrotestosterone sulfate（VIP=1.02,P<0.01）,adrenocorticosterone（VIP=1.43,P<0.01）,dihydrotestosterone sulfate（VIP=1.43,P<0.01）in female athletes),dehydroisosterone sulfate（VIP=1.02,P<0.01）,adrenocorticosterone（VIP=1.43,P<0.01）,dihydrotestosterone（VIP=1.36,P<0.01）,aldosterone（VIP=1.36,P<0.01）,cortisol（VIP=1.24,P<0.01）,melatonin（VIP=1.24,P<0.01）and progesterone（VIP=1.24,P<0.01）in female athletes.<0.01)and progesterone（VIP=1.19,P<0.01）were the differential metabolites at the loading and adjustment weeks.（3）Relationship between blood metabolites and commonly used biochemicals: in male athletes,both metabolites testosterone and dihydrotestosterone were significantly correlated with conventional biochemical testosterone（r=0.535,0.512,P=0.000,respectively）;metabolite 11-deoxycortisol was significantly correlated with commonly used biochemical cortisol（r=0.507,P=0.000）;metabolite dihydrotestosterone was significantly correlated with haemoglobin（r=0.509,P=0.000）;the metabolite corticosterone was significantly associated with conventional biochemical cortisol（r=0.514,P=0.000）and deoxycorticosterone with haemoglobin（r=0.525,P=0.000）in female athletes.（4）Relationship between metabolites in urine and common biochemical indicators:only progesterone was significantly correlated with haemoglobin in female athletes（r=-0.511,p=0.000）.Conclusions:（1）Urinary steroid metabolites,cortisol,corticosterone and dehydroisandrosterone sulphate in male athletes;corticosterone,dehydroisandrosterone sulphate,androstenedione,dihydrotestosterone and aldosterone in female athletes can be used as high-throughput non-invasive indicators of training load monitoring in outstanding athletes,respectively.（2）Blood steroid metabolites,cortisol,corticosterone and dehydroisandrosterone sulphate in male athletes;cortisol,corticosterone,dehydroisandrosterone sulphate,androstenedione,testosterone,dihydrotestosterone,aldosterone,melatonin and progesterone in female athletes can be used as high-throughput indicators of training load monitoring in outstanding athletes,respectively.（3）Blood steroid metabolites reflect changes in testosterone,cortisol and haemoglobin in male athletes and cortisol and haemoglobin in female athletes in the commonly used biochemicals.Urinary steroid metabolites only respond to changes in haemoglobin in female athletes in the commonly used biochemical indicators.