Hayesetal.SpringerPlus2013,2:18 http://www.springerplus.com/content/2/1/18 a SpringerOpen Journal RESEARCH Open Access The effects of a formal exercise training programme on salivary hormone concentrations and body composition in previously sedentary aging men Lawrence D Hayes1,2*, Fergal M Grace1, Nick Sculthorpe1,3, Peter Herbert4, John WT Ratcliffe1, Liam P Kilduff5 and Julien S Baker1 Abstract Alteration inbody composition,physicalfunction,and substrate metabolism occur withadvancingage. These changes may be attenuated byexercise. This study examined whether twenty eight, previously sedentary males (62.5 ± 5.3years ofage; body mass of89.7 ± 16.4 kg) adhering to the ACSM minimum guidelines for aerobic exercise for sixweeks would improve exercise capabilities, body composition and salivary hormone profiles.After sixweeks of adhering to theguidelines,salivarytestosterone and vo (absolute and relative) increased (p< 0.05), 2max whilst body fat percentage and body mass decreased (p <0.05).Peak power output, fat free mass and cortisol values were not significantly different.Interestingly, salivary testosterone correlated inversely withbody fat percentage (R2= .285, p= 0.011). These results suggest that despiteprevious inactivity, older males can achieve improvements incardiorespiratory fitness, body composition and anabolism by adhering to simple lifestyle changes. Keywords: Cortisol, Testosterone, Sarcopenia, Aging, Physical activity Introduction et al. (2001) reported that total and free testosterone Advancingageisassociatedwithalterationsinbodycom- decreased linearly with age from 21-45 yr onwards and position, physical function, and substrate metabolism. approximately 25-30% of men over 60 yr age have hypo- Loss of skeletal muscle mass (sarcopenia) contributes to gonadal testosterone levels. Testosterone insufficiency declines in muscle strength and function along with has been shown to lead to increased visceral fat mass, diminishedqualityoflife(Sattleretal.,2009).Age-related decreased lean body mass, and decreased muscle strength bodycompositionchangesandlossesinmusclemassplay (Wu et al., 2010). It has been widely reported that testos- importantrolesinfrailty(Wuetal.,2010). teronereplacementincreasessynthesisofmyofibrillarpro- Coincidentwiththeage-relateddeteriorationsinclinical teins, total body cell mass, muscle strength (Urban et al., status, endogenous production of anabolic hormones 1995), and reduced trunk and visceral fat, blood pressure, declines(Harmanetal.,2001).Testosteroneplayskeyroles lipids,and improvesinsulinsensitivity(Brandetal.,2011). in regulating muscle mass and fat free mass (Hayes et al., Increasing observational evidence also suggests a protec- 2010), and it declines with age in both men (Feldman tiveroleofendogenoustestosteroneinmen’scardiovascu- et al., 2002) and women (Davison et al., 2005). Harman lar health (Brand et al., 2011). Some research has shown that circulating concentrations of anabolic hormonessuch astestosteroneinoldermenarerelatedtoincreasedlevels *Correspondence:[email protected] 1InstituteofClinicalExerciseandHealthScience,UniversityoftheWestof of physical activity, muscle function, and aerobic power Scotland,Hamilton,Scotland (Herbst and Bhasin, 2004). Therefore, to counter the age- 2SchoolofHumanSciences,LondonMetropolitanUniversity,166-220 associated decline in anabolic hormones, regular exercise HollowayRoad,LondonN78DB,UK has been suggested as a possible nonpharmacological Fulllistofauthorinformationisavailableattheendofthearticle ©2013Hayesetal.;licenseeSpringer.ThisisanOpenAccessarticledistributedunderthetermsoftheCreativeCommons AttributionLicense(http://creativecommons.org/licenses/by/2.0),whichpermitsunrestricteduse,distribution,andreproduction inanymedium,providedtheoriginalworkisproperlycited. Hayesetal.SpringerPlus2013,2:18 Page2of5 http://www.springerplus.com/content/2/1/18 intervention to elevate the concentration of circulating at the end of the sessions. These ranged between 13 and anabolichormonesinolderindividuals. 15duringthefinal3weeks;somewhathardtohard. Exercise has been observed to improve quality of life On both testing days, participants arrived at the same by decreasing body fat and obesity, increasing muscle time of day to exclude diurnal variation of measurements strength,improving balance,gait,andmobility,decreasing (Hayes et al., 2010). Prior to experimental data collection the likelihood of falling, improving psychological health participants were fully habituated and familiarized with and reducing arthritis pain. Exercise has also been impli- data collection and testing procedures. This was done to cated in reducing the risk of developing coronary heart eliminate any learning effect. The order of measurements disease, hypertension, osteoporosis, cancer, and diabetes were; saliva sampling, body composition, peak power (Wroblewskietal.,2011).TheACSMguidelineforaerobic assessment, and VO assessment. A minimum of 5 2max exercise in older individuals is “a minimum of 5 d∙wk-1 of min recovery was allowed between the peak power and moderate intensity, or a minimum of 3 d∙wk-1 of vigorous VO assessment to allow replenishment of the ATP/ 2max intensityexercise,andtoaccumulateatleast30min∙d-1of PCrsystem.Theinvestigationmettheethicalstandardsas moderate-intensity activity, in bouts of at least 10 min outlined previously (Harriss and Atkinson, 2011) and was each; continuous vigorous activity for at least 20 min∙d-1” approvedbytheUniversityoftheWestofScotlandEthics (Nelsonetal.,2007).Itisapparentthatresistanceexercise Committee. can maintain muscle mass and strength in older indivi- duals.Ithasalsobeenshownthattestosteronesupplemen- tationcanincreasemusclemassintheelderly.Asexercise Participants is known to increase levels of testosterone (Caruso et al., Twenty eight males 62.5 ± 5.3 years of age, with a sta- 2012; Lovell et al., 2012), the primary aim of the present ture of 174.5 ± 6.4 cm, and body mass of 89.7 ± 16.4 kg investigation was to examine whether exercise could pro- participated. All participants were sedentary (they were duce improvements in common symptoms of the aging not part of an organized exercise program and did not process. Participants adhered to the ACSM guideline for meet the ACSM minimum guidelines for aerobic exer- aerobic exercise in older individuals for six weeks. A fur- cise). Participants had abstained from alcohol, caffeine ther aim was to investigate whether salivary hormones and exercise for 24 h prior to the investigation. Partici- mayreflectphysiologicalchangesassociatedwithfitness. pantswokeupat~07:30andarrivedatthelaboratoryina four-hour fasted condition as requested according to self- reporting. A conventional overnight fast was used unless Materials and methods participants were scheduled to arrive in the afternoon, in Participants were tested at two points, separated by six whichcaseafourhourfastwasused.Toincreasereliabil- weeks. In the six weeks between testing sessions, partici- ity,participantswereallocatedthesameappointmenttime pantswereprescribedwithacombinationofaerobic,an- on both visits to the laboratory. Participants reported to aerobic and resistance training activities. Participants the laboratory on two separate days, separated by six were instructed to exercise twice a week for two weeks weeks. Preceding data collection and exercise, all subjects and by the third week achieve 130 min∙wk-1 of moderate had an ECG following ACSM guidelines, and all com- exercise. For the final three weeks, ∼150 min∙wk-1 of pleted health history questionnaires. All subjects were moderate to vigorous work was reported. Exercise acti- deemed fit to participate in the study, and were signed of vities were overseen by a member of the research team. ashealthybyamedicalDoctor. To ensure levels of low, moderate and some high inten- sity exercise, intensity was confirmed using participant Bodycomposition heart rates(Polar,Finland). Height was measured to the nearest 0.1 cm using a sta- All participants met the ACSM minimum guidelines diometer (Seca, Birmingham, UK) and body mass to the for aerobic exercise but did not excessively exceed them. nearest 0.1 kg (Tanita MC-180MA Body Composition Activities consisted of walking, cycling, hill walking and Analyzer, Tanita UK Ltd.). A multi frequency bioelec- resistance training. Participants achieved an average trical impedance analyzer ((BIA) Tanita MC-180MA heart rate (HR) between 70 and 80% of HR by the Body Composition Analyzer, Tanita UK Ltd.) was used max end of the programme (Table 1). RPE's were also noted to measure body composition. Coefficient of variance (CV) of the impedance measure was 0.4%. The Tanita Table1Mean±SDHRexpressedasapercentageof GMON software (v1.7.0) generated values for fat free HR duringthesixweeksofexercise.Nosignificant max mass(FFM)andbodyfatpercentage.Individualhaemato- differenceswereobserved crit (Hct) concentrations were used as indirect measures Week1 Week2 Week3 Week4 Week5 Week6 ofhydrationstatustovalidateBIAresults.Concentrations 74.7±4.2 75.6±3.9 75.4±4.5 74.5±4.7 74.0±5.0 75.0±5.4 were 44.8 ± 4.1 and 46.0 ± 2.1 for week 0 and week 6 Hayesetal.SpringerPlus2013,2:18 Page3of5 http://www.springerplus.com/content/2/1/18 respectively.ValuesobtainedfromBIAweresupportedby rpm and work-rate was increased every minute by raising skinfoldmeasurementsusingHarpendencalipers. thedampersettingbyoneuntiltheparticipantwasunable to continue despite vigorous encouragement. The partici- Salivacollectionandanalysis pants cycled at a self-selected pedal rate which remained Methods have been described previously (Hayes et al., constantthroughoutthetest(70–90rpm).Pulmonarygas 2012). Briefly, whole salivary samples of approximately exchange was measured breath-by-breath throughout 1.8 mL were collected via expectoration into graduated the exercise test. Participants breathed through a low- 2 ml cryovials (Salimetrics, State College, PA). To pre- resistance volume transducer, which had a dead space of vent potential blood contamination of saliva, resulting in 90 ml. Gas was continuously drawn down a capillary line an overestimation of hormone concentrations, partici- into rapid-response gas analysers (Metamax II, Cortex, pants were advised to avoid brushing their teeth and Leipzig,Germany)andgasexchangevariableswerecalcu- drinking hot fluids 2 h prior to reporting to the study lated and displayed breath-by-breath after accounting for venue. Salivary samples were collected and transported the delay between the volume and concentration signals. to a freezer immediately where they remained at -80ºC The volume transducer was calibrated before each test until assay. Samples were assayed in duplicate (without with a 3-l calibration syringe and the analysers were cali- separation or extraction) for cortisol and testosterone brated with precision-analysed gases that spanned the using commercially available immunoassay protocols expected range of expired O and CO concentrations. 2 2 (Salimetrics, State College, PA). All samples were assayed HRwasrecordedevery5susingshort-rangetelemetry.A for salivary cortisol using a high-sensitivity enzyme im- fingertip blood samplewascollectedinto aportable auto- munoassay (EIA) (Salimetrics, State College, PA) with a mated lactate analyser (Lactate Pro, Arkray, Inc., Kyoto, lower limit of sensitivity of <0.19 nmol/L, and average Japan) within 45 s of the termination of exercise. VO 2max intra- and inter-assay coefficients of variation 4.13% and was calculated as the highest 20 s value achieved during 8.89%,respectively.Salivasampleswereassayedfortestos- thetest.Theramptestdataforeachindividualparticipant terone using EIA with a lower limit of sensitivity of 5.20 weresubsequentlyexaminedtoassesstheextenttowhich pmol/L, and average intra- and inter-assay coefficients of the secondary criteria (based on maximum values for variationlessthan10%and15%,respectively. RER,HRandblood[lactate])couldbeusedtoconfirm,or otherwise,themeasuredVO :ForRER,theVO values 2max 2 Peakpowerassessment correspondingtoRERvaluesof1.10and 1.15werecalcu- An adaption of the Wingate anaerobic test consisted of lated and compared to the VO : For HR, the number 2max a 10-s maximal sprint against constant resistance on an and proportion of participants who satisfied the criterion air-braked cycle ergometer (Wattbike Ltd., Nottingham, ofachievingaHRwhichwaswithin±10b/min(or5%)of UK). For each subject the damper resistance was set at theage-predictedmaximum(220-ageinyears)wascalcu- 10 (described as “heavy gearing” by the manufacturer). lated. Finally, the number and proportion of participants Considering the participants were mostly aged 60-70 yr who satisfied the criterion of achieving a peak blood old, it would have been unlikely that any would have [lactate]of>6mMwasestablished. achieved over 1350 W, which was the case. All subjects reached their peak power by 7 s, usually by 5 s. All sub- Statisticalanalysis jectscompleted a standardized3-minwarm-upinvolving Data were analyzed using SPSS (version 18) (IBM North pedalling at 60 rpm interspersed with three 2- to 3-s all- America, New York, NY, USA). Conventional methods, out sprints. A recovery period of 5 min was allowed mean,standarddeviation(SD),repeatedmeasuresanalysis between the warm-up and the test. The test commenced of variance (ANOVA) with bonferroni correction, and from a standing start. Subjects were verbally encouraged Pearson’s correlation were used to analyze participant throughout the test to avoid pacing and to sustain their descriptiveandexperimentaldata.Hormonalandexercise- supramaximaleffortthroughoutthetest.Thepowerout- testperformancedatawereanalyzedwithANOVA.Signifi- put was calculated each second for the duration of the cancewassetaprioriatp≤0.05. testandpeak powerover1swasrecorded. Results Vo assessment Aerobic capacity increased (p < 0.05) after six weeks 2max A 3 min warm up on an air-braked cycle ergometer activity compared to baseline (Table 2). Peak power out- (Wattbike Ltd., Nottingham, UK), preceded the ramped putwasnot significantlydifferent.Thereweresignificant protocol. Participants commenced their VO test on increases in resting salivary testosterone (p < 0.05) from 2max different cadences dependent on their power output baseline to six weeks but not cortisol. Percentage body values and maintained these cadences throughout the fat decreased (p < 0.05), as did body mass (p < 0.05). test until exhaustion. The cadences were70, 75, 80, or 85 However, FFM was not significantly altered. Salivary Hayesetal.SpringerPlus2013,2:18 Page4of5 http://www.springerplus.com/content/2/1/18 Table2Exerciseperformance,hormonal,andbody etal.(2012)testedparticipants70–80years.Astestoster- compositionvaluesaftersixweeksoftheACSM one is known to decline with increasing age (for a review minimumguidelinesforaerobicexercise seeWroblen1991),atapproximately1%peryearafterthe Variable Week0 Week6 age of 40 years (Gray et al., 1991), the ability of increased VO (ml·kg·min-1) 26.85±5.31 28.55±4.80 exercise to elevate testosterone may be blunted in older 2max p=.012 individuals. VO (L·min-1) 2.38±0.46 2.51±0.43 Assalivarytestosteronereflectstheunbound(free),bio- 2max available steroid hormone fraction found in the general p=.035 blood circulation, the increase found in the present study Peakpoweroutput(W·kg-1) 7.58±1.68 7.77±1.58 has important implications for older individuals. The p=.580 higher free testosterone, may indicate an improved “bio- Peakpoweroutput(W) 672.80±157.98 682.7500±152.13 activitystatus”inthebloodoftheparticipants.Higherfree p=.344 testosteronelevelshavebeenassociatedwithgreaterbone Testosterone(pmol·L-1) 378.80±127.33 484.30±182.35 mineral density in men (Murphy et al., 1993) and are re- p=.010 portedly inversely associated with fat mass (Abbasi et al., Cortisol(nmol·L-1) 2.76±1.47 3.20±1.45 1998).Freetestosterone concentrationisalsoa significant p=.156 independent predictor of lean body mass and muscle Totalbodymass(kg) 90.44±18.09 89.28±17.36 strength (Baumgartner et al., 1999). Salivary testosterone increases found in the present study, coupled with no p=.003 observed change in resting cortisol levels suggest an FFM(kg) 63.76±8.69 64.70±8.01 enhanced anabolic environment in participants, however p=.084 noincreaseinFFMwasnoted.Nevertheless,reductionsin Bodyfatpercentage(%) 28.73±5.00 26.69±5.20 total body mass and body fat percentage were observed. p=.003 The relationship between testosterone and body fat per- Valuesaremean±SD;VO =maximaloxygenuptake,FFM=fatfreemass. 2max centage observed in the current investigation is in agree- pvaluesarereportedfordifferencesbetweenweek0andweek6. ment with the findings of Abbasi et al. (1998) who noted testosterone correlated inversely with body fat percentage that total testosterone and free testosterone have been (R2 = .285, p = 0.011). Vo correlated inversely with identifiedaspredictorsofFFMandtotaladiposemass. 2max FFM (R2 = .293, p = 0.007), total body mass (R2 = .551, Participants experienced increases in VO after the 2max p<0.001),andbodyfatpercentage(R2=.711,p<0.001); sixweeksofincreasedactivity.Thiswasnotanunexpected yet positively with testosterone (R2 = .268, p = 0.017) and result as previous studies have found that even moderate peakpoweroutput(R2=.281,p=0.010). exercise can increase VO of older men (Niederseer 2max etal.,2011).Asabsolutevalueswereincreasedfrombase- Discussion line, we can conclude that cardiorespiratory adaptations Our data suggest that six weeks of increased physical didoccurratherthanrelative valuesincreasingpurelydue activity in previously sedentary men can improve bo- to body mass decreases. Peak power output (relative and dy composition, exercise performance and testosterone absolute) remained unaltered after six weeks of increased levels. As suggested by Herbst and Bhasin (2004), testos- activity. However, this is unsurprising as participants did terone was related to increased levels of physical activity not engage in high intensity activities likely to improve and aerobic power in older men. Contradictory to the power output. As with FFM, there was a trend for in- present investigation, Lovell et al. (2012) reported that creasedpeakpoweroutputafterthesixweekintervention 16 weeks of resistance training or 16 weeks of aerobic butthisdidnotreachsignificance. training at 70% of VO for 45 min three times per Despite the encouraging findings of the present investi- 2max week did not provide sufficient stimulus to significantly gation, a limitation was the relatively small sample size increase resting testosteroneorfree testosteroneinolder and short observation period. Therefore, future investiga- men.Methodologicaldiscrepanciesmayexplain these dif- tions utilizing a longer study period with a larger sample ferent findings. Firstly, Lovell et al. (2012) recruited parti- sizemaybebeneficial. cipants who were moderately active with walking and In conclusion, our data demonstrates that six weeks of gardening as their main activities whereas the present in- the ACSM minimum guidelines for aerobic exercise in- vestigation recruited participants who self-reported no crease resting salivary testosterone of previously inactive organised physical activity throughout a week. However, oldermen.Furthermore,bodycompositionandmaximum the most reasonable explanation is the age difference of oxygen uptake improvements were noted after moderate participants.Inthecurrentinvestigation,werecruitedpar- lifestyle changes. As sports medicine clinicians, we must ticipants aged 55-74 years to participate, whereas Lovell encourage people to become or remain active at all ages. Hayesetal.SpringerPlus2013,2:18 Page5of5 http://www.springerplus.com/content/2/1/18 It is crucial that increased activity levels are maintained MurphyS,KhawKT,CassidyA,CompstonJE(1993)Sex-hormonesandbone- habitually as improvements in VO are lost once the mineraldensityinelderlymen.BoneMiner20(2):133–140 2max NelsonME,RejeskiWJ,BlairSN,DuncanPW,JudgeJO,KingAC,MaceraCA, stimulus of exercise is removed (Lovell et al., 2012). This Castaneda-SceppaC(2007)PhysicalActivityandPublicHealthinOlder study and those reviewed here, document the possibility Adults:RecommendationfromtheAmericanCollegeofSportsMedicineand toimprove physical fitness acrossthe ages via simple life- theAmericanHeartAssociation.MedSciSportExerc39(8):1435–1445 NiederseerD,Ledl-KurkowskiE,KvitaK,PatschW,DelaF,MuellerE,NiebauerJ stylechanges. (2011)SalzburgSkiingfortheElderlyStudy:changesincardiovascularrisk factorsthroughskiingintheelderly.ScandJMedSciSport21:47–55 Competinginterests SattlerFR,Castaneda-SceppaC,BinderEF,SchroederET,WangY,BhasinS, Theauthorsdeclarethattheyhavenocompetinginterest. KawakuboM,StewartY,YarasheskiKE,UlloorJ,CollettiP,RoubenoffR,Azen SP(2009)TestosteroneandGrowthHormoneImproveBodyComposition Authors’contributions andMusclePerformanceinOlderMen.JClinEndocMetab94(6):1991–2001 WroblenA(1991)Androgensintheagingmale.JClinEndocMetab LDHwrotethemanuscript,conductedthestatisticalanalysis,collecteddata 73(2):221–224 andconductedtheEIAs.FMGparticipatedinthedesignofthestudyand WroblewskiAP,AmatiF,SmileyMA,GoodpasterB,WrightV(2011)Chronic datacollection.NSparticipatedinthecoordinationofthestudyanddata collection.PHcoordinatedtheinvestigation.JWTRcollecteddata.LKK exercisepreservesleanmusclemassinmastersathletes.PhysSportsmed 39(3):172–178 collectedthedata.JSBparticipatedinthedesignofthestudy.Allauthors WuIC,LinXZ,LiuPF,TsaiWL,ShieshSC(2010)Lowserumtestosteroneand readandapprovedthefinalmanuscript. frailtyinoldermenandwomen.Maturitas67(4):348–352 Authordetails UrbanRJ,BodenburgYH,GilkisonC,FoxworthJ,CogganAR,WolfeRR,Ferrando 1InstituteofClinicalExerciseandHealthScience,UniversityoftheWestof A(1995)Testosteroneadministrationtoelderlymenincreasesskeleta-muscle Scotland,Hamilton,Scotland.2SchoolofHumanSciences,London strengthandprotein-synthesis.AmericanJournalofPhysiology- EndocrinologyandMetabolism296(5):E820–E826 MetropolitanUniversity,166-220HollowayRoad,LondonN78DB,UK. 3DepartmentofSportandExerciseSciences,UniversityofBedfordshire, Bedfordshire,UK.4SchoolofSport,HealthandOutdoorEducation,Trinity doi:10.1186/2193-1801-2-18 SaintDavid,UniversityofWales,Wales,UK.5DepartmentofSportsScience, Citethisarticleas:Hayesetal.:Theeffectsofaformalexercisetraining SwanseaUniversity,Swansea,UK. programmeonsalivaryhormoneconcentrationsandbodycomposition inpreviouslysedentaryagingmen.SpringerPlus20132:18. 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Submit your manuscript to a JClinEndocMetab86(2):724–731 journal and benefi t from: HarrissDJ,AtkinsonG(2011)Update-EthicalStandardsinSportandExercise ScienceResearch.IntJSportsMed32(11):819–821 7 Convenient online submission HayesLD,BickerstaffGF,BakerJS(2010)Interactionsofcortisol,testosterone,and resistancetraining:influenceofcircadianrhythms.ChronobiolInt 7 Rigorous peer review 27(4):675–705 7 Immediate publication on acceptance HayesLD,GraceFM,KilgoreJLYJD,BakerJS(2012)Diurnalvariationofcortisol, 7 Open access: articles freely available online testosterone,andtheirratioinapparentlyhealthymales.SportSPA9(1):5–13 7 High visibility within the fi eld HerbstKL,BhasinS(2004)Testosteroneactiononskeletalmuscle.CurrOpinClin Nutr7(3):271–277 7 Retaining the copyright to your article LovellDI,CuneoR,WallaceJ,McLellanC(2012)Thehormonalresponseofolder mentosub-maximumaerobicexercise:Theeffectoftraininganddetraining. Submit your next manuscript at 7 springeropen.com Steroids77(5):413–418