Functional Threshold Power (FTP) an FT(20 min) of 3.98 w/kg internet definition an FT(20 min) of 3.98 w/kg an FT(20 min) of 3.98 w/kg an FT(20 min) of 3.98 w/kg internet definition an FT(20 min) of 3.98 w/kg an FT(20 min) of 3.98 w/kg an FT(20 min) of 3.98 w/kg an FT(20 min) of 3.98 w/kg an FT(20 min) of 3.98 w/kg