title: Forearm muscle quality as a better indicator of physical performance than handgrip strength in older male ground golf players aged 70 to 89.
abstract: To examine the associations between absolute and relative handgrip strength (HGS) and physical performance.
  
  
  
  A total of 135 old men aged 70-89 years had muscle thickness (MT) measured by ultrasound at anterior forearm (MT-ulna). Maximum voluntary HGS was measured for the dominant hand. Relative HGS was calculated as ratios of HGS to MT-ulna (HGS/MT-ulna, kg/cm), HGS to forearm girth (HGS/forearm-girth, kg/cm), and HGS to body mass (HGS/body mass, kg/kg). Physical performance was also assessed using the short physical performance battery (SPPB).
  
  
  
  Age was significantly correlated with absolute and relative HGS (r=-0.479 and r=-0.315 to -0.427, respectively all p<0.001) and physical performance (walking speed, r=-0.218, p=0.011; chair stand, r=0.348, p<0.001), but not with SPPB score (r=-0.083). Absolute HGS was positively correlated with usual-walking speed (r=0.354, p<0.001) and was inversely correlated with chair-stand time (r=-0.386, p<0.001). The strongest correlations were seen between HGS/MT-ulna and usual-walking speed (r=0.426, p<0.001) or chair-stand (r=-0.461, p<0.001). Stepwise regression analysis revealed that HGS/MT-ulna was a significant predictor for U-walk speed (R2=0.205) and chair-stand time (R2=0.241) while absolute HGS was not a significant predictor of either one.
  
  
  
  Thus, we suggest that forearm muscle quality (HGS/MT-ulna) may be a stronger predictor of physical performance than absolute HGS in active old men.
authors.affiliation: Department of Sports and Life Sciences, National Institute of Fitness and Sports in Kanoya, Kagoshima, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Abe
authors.forename: R S
authors.initials: RS
authors.lastname: Thiebaud
authors.forename: J P
authors.initials: JP
authors.lastname: Loenneke
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D005542:Forearm / Q000502:physiology*; D006055:Golf; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*