BACKGROUND: The alpha-actinin-3 (ACTN3) R577X polymorphism has been associated with muscle power performance in cross-sectional studies. METHODS: We examined baseline knee extensor concentric peak power (PP) and PP change with approximately 10 weeks of unilateral knee extensor strength training (ST) using air-powered resistance machines in 71 older men (65 [standard deviation = 8] years) and 86 older women (64 [standard deviation = 9] years). RESULTS: At baseline in women, the XX genotype group had an absolute (same resistance) PP that was higher than the RR (p =.005) and RX genotype groups (p =.02). The women XX group also had a relative (70% of one-repetition maximum [1-RM]) PP that was higher than that in the RR (p =.002) and RX groups (p =.008). No differences in baseline absolute or relative PP were observed between ACTN3 genotype groups in men. In men, absolute PP change with ST in the RR (n = 16) group approached a significantly higher value than in the XX group (n = 9; p =.07). In women, relative PP change with ST in the RR group (n = 16) was higher than in the XX group (n = 17; p =.02). CONCLUSIONS: The results indicate that the ACTN3 R577X polymorphism influences the response of quadriceps muscle power to ST in older adults.
BACKGROUND: The alpha-actinin-3 (ACTN3) R577X polymorphism has been associated with muscle power performance in cross-sectional studies. METHODS: We examined baseline knee extensor concentric peak power (PP) and PP change with approximately 10 weeks of unilateral knee extensor strength training (ST) using air-powered resistance machines in 71 older men (65 [standard deviation = 8] years) and 86 older women (64 [standard deviation = 9] years). RESULTS: At baseline in women, the XX genotype group had an absolute (same resistance) PP that was higher than the RR (p =.005) and RX genotype groups (p =.02). The women XX group also had a relative (70% of one-repetition maximum [1-RM]) PP that was higher than that in the RR (p =.002) and RX groups (p =.008). No differences in baseline absolute or relative PP were observed between ACTN3 genotype groups in men. In men, absolute PP change with ST in the RR (n = 16) group approached a significantly higher value than in the XX group (n = 9; p =.07). In women, relative PP change with ST in the RR group (n = 16) was higher than in the XX group (n = 17; p =.02). CONCLUSIONS: The results indicate that the ACTN3R577X polymorphism influences the response of quadriceps muscle power to ST in older adults.
Authors: Fleur C Garton; Peter J Houweling; Damjan Vukcevic; Lyra R Meehan; Fiona X Z Lee; Monkol Lek; Kelly N Roeszler; Marshall W Hogarth; Chrystal F Tiong; Diana Zannino; Nan Yang; Stephen Leslie; Paul Gregorevic; Stewart I Head; Jane T Seto; Kathryn N North Journal: Am J Hum Genet Date: 2018-04-26 Impact factor: 11.025
Authors: Suchi Sood; Erik D Hanson; Matthew J Delmonico; Matthew C Kostek; Brian D Hand; Stephen M Roth; Ben F Hurley Journal: Eur J Appl Physiol Date: 2011-06-11 Impact factor: 3.078
Authors: Sean Walsh; Bethany K Kelsey; Theodore J Angelopoulos; Priscilla M Clarkson; Paul M Gordon; Niall M Moyna; Paul S Visich; Robert F Zoeller; Richard L Seip; Steve Bilbie; Paul D Thompson; Eric P Hoffman; Thomas B Price; Joseph M Devaney; Linda S Pescatello Journal: J Appl Physiol (1985) Date: 2009-07-23