Potential benefits of marathon training on bone health as assessed by calcaneal broadband ultrasound attenuation

The purpose of this study was to determine calcaneal broadband ultrasound attenuation (BUA) of marathon race participants and compare this information with previously obtained non-native data. BUA was assessed using the McCue CUBA clinical device in 217 male and 184 female runners, aged 20-93 yr, participating in the 2004 Flora London Marathon. The normative data included 267 men and 334 women, aged 20-80 yr. A significantly higher mean BUA (p < 0.001) was observed for all the men (91.2 dB/MHz, standard deviation [SD] 18.2 dB/MHz) in the study compared to the women (81.6 dB/MHz, SD 17.0 dB/MHz) and for the marathon runners compared to the nonrunners (p < 0.001) among men (97.2 dB/MHz, SD 17.6 dB/MHz and 87.7 dB/MHz, SD 17.6 dB/MHz, respectively) and women (89.2 dB/MHz, SD 14.2 dB/MHz and 77.4 dB/MHz, SD 17.0 dB/MHz, respectively). A significant decline in BUA with age was observed in all males and females, with the males starting from a higher baseline and with the rate of decline significantly ameliorated by marathon training (from -0.35 to -0.25 dB/MHz per year in men and -0.51 to -0.15 dB/MHz per year in women). This study provides observational evidence in support of the potential benefits of weight-bearing exercise, such as marathon training and running, on BUA of the calcaneus, an index of bone mineral density.