Bone mass, bone mineral density and muscle mass in ...

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]mtrl/al 01 SporlS Scieuces, 2002, 20, 59 1-597

Bone mass, bone mineral density and muscle mass in professional golfers C. DORADO,' j. SANC HIS MOYSl,' G. VICENTE,' l.A. SERRANO,' L.P. RODRi GUEZ' and J.A.L. CALBET" ' Deparrallumw de Educación Física, Umversidad d~ Los Palmas de Gra" Canan'a. Campus Universlfano de Tr.ifira. 35017 Las Palmm de GI'all Cólftaria ami "Departa mento de A reJicma Físico y da RrlrabiliratiólI, Umverúdad Compluumse. 28040 ,\>Iadrid. SfJl('Inal compcntions for al leaSl 16 years ( 16.7 ± 5.9 years; mean ±sJ. The mean lime spent in golfing acuvlUes was 5.4± 1.5 h ' day l. Thc control group consisled of sed entary lOdl\;dua!s who had nut taken pur! m sport or any omer kind of physlcaJly demanding 3CQ\1ry in me previou!. 5 yean. CalclUm intakc wa~ calculated from me daily consumption of dalr)' producLS reponed by me partio.pams. No omer nutritionaJ analyse.!. were performed. For both groups, the malO excluslon critena were a medical history of bOrle rnctabolic dlsease or medlcal disorden known lO affeel skelclal tissue. AH Lhe golfcrs and 15 of me conltOl!1 were righl-handed .

ASJcssmcm of bc>Jy compcsftlcm TOlal :md rcglomt! body composmon was measured using dual-energy X-my absorpuomeuy (OXA) (QDR1500, Hologic Curp., \'\ahham, ¡\olA). a lechnique thal has been reported to have excellem "'3lidlty snd reliablhty comparcd ",ilh omer methods (H eymsfield t'f al., 1990; S\'endsen ef JI., I 993¡ Wang el al., 1999). Before each examlnal1on. me scanner was calibrttled using phanloms pro\'lded by the manufacturer. Seans were performed al lo'" spced and maximal resolution . From Ihe " 'hole-body scans, lean body mass, body ral, 100al a~a snd bOlle mineral comen! ",ere detcrmined . Bone mmeral density was calculated by dividing bone mmcral camem by total area. From Ihe whole-body scan , me following sub-regions were analysed: all four limbs and me pelVIS, neck, hend , [horade and abdominal regions. The arm region mdudcd me band, roreann and armo and wa!'i separatcd from lhe trunk by ao 1OdlOed hne erossmg me humeroscapula r joml such Ihal the humernl bead was localed m me arm region . The leg region meluded tbe fOOl, lower and upper leg :md was defined by an inehned line passing Just belo" me pel\;s crossing lhe neck of me femur. The head region comprised aU skelcral pans of lhe skull aud cervical vertebra above:: a horizontal ¡¡nc passlng IUS! bc.low me jawbone. Bone mass In ,be lumbar spine:: and me proximal region of the femur was also eSllmaled rrom a sccond scan. To sa\'e time and ~duce X-ruy exposure, only me left femur was scanned. Values for me femorol neck, Ward 's triangle and tnler-t.roehanteric sub-reglons ~re also delcrmmcd. \~rard 's mangle, deñned as me area

Table l. Phy.acal (:har.U:II~rtSUC5 oflhC' partlelpanlS (mt'lln tsJ Vanable AgC' (years) Helghl (m) TOlal bod)' ma~s (kg)

Golfe::n 2Q'!: I

1.78 1.0.0 1

% Fal

78.6 t 2.3 2.85:t 0.08 59 l:t l.:! 16.0.:1 1.8 19.9 "t IR

ANom"W1I(1II D.\\C" OOnc

m1nCT1Il mnlen!.,

TOlal BMC (k¡.) T01211eao mau (kg)

TOI2I body fl\1 (kg)

Controls

P

25± 1

N.'

1.17 i ll.02 7 1 I .±: 2.3 2.77:t 0.0 1 55.):1 1.4 15,4 :t 1.6 20.5! 1.8

N.~.

N.' N.'

higher in me dominant rhan in the non-dominant limb ofthe golfers (P < 0.05 ); the 2% ditfcrence in bODe mineral conten t bctween me left and nghr arms of the colltrols was nOl significant. Although golf participanon appeared [O be associated with increased bODe mineral content in the dominant arm, me small inter-arm difference between golfers and controls (6 v.( 2%) was nOf srauslically significant. Figure 2 illustrares me regional bone mineral contenlS and densities derived from me whoJe-body sean. as well as from specific regional analysis performed on the leh hip and lumbar spine. Femoral and lumbar spine bone mineral conteat and densily were similar in m e rwo groups (F ig. 2). Good correlatioDs were ohserved berv.'een limh bone mineral content and me corresponding muscle mass (r > 0.70). wjm the exception ofilie dominant arm in me golfers. when bone mineral content corrclated more \....eakly with muscle mass ( r = 0.60, P < O.OS) (Table 2).

,

We found no significanl ditferences in regional bone mass or densiry between lbe two groups, even after accounting foc small. srarisrically ¡nsignificanl differences in body sae. The golfers reveaJed sorne muscle hypertrophy in the dominant compared wilb lhe nondominant arm (+9 %); in sedcntary individuals, the typical inter-arm muscle mass difference is only 4-5% (Calbet et al., 1998, 1999.2001 ; Sancrus Moysi el al., 1998). The percen! body fal of lhe golfers was hlgh compared with rhat of omer athletes srudied previously in our laborslOry, induding soccer players, profcssional tcrmis players and profcssionaJ vollcyball players (Calbct III al.• 1998, 1999. 200 1). Perhaps the tow energy cost of golf participation (Hendelman et al., 2000), insufficiem physical conditioning or excessive energy intaKe cou ld explain this finding. As illustrated in Table 3, profcssional tennis players srudied previously

Arms

, 5

Discussion

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Fig. 1. Umb composition in professional golfees and controls (mean ± sJ . • P < 0.05, golfers versus conrrols. Iimb versus left 11mb.

t P < 0 .05, nght

594

Dorado et al. BMO (kg·m- 2)

BMe (kg)

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00050.01 Q.Q15 002 0025003 0_035

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