FWIW,I know when I'm single digit BF by looking in the mirror. When I reach that point when my glutes have clearly visible striations and I have veins popping in my lower abdominals and in my obliques;I'm under 10%.
Used to get pinched w the calipers from several personal trainer friends over the years and we'd joke around and guess what my BF was.
Until this summer that is lol,headed back up to NY for a family event and stopped by my old training partners gym for a quick session. He said you wanna check your BF while you're here? I said,nah I'm good I know Im single digits..He says how are you so sure fatboy?? So I showed him my striated glutes lol. He said and I qoute," I FUCKING HATE YOU GET OUTTA MY GYM AND TAKE YOUR GLUTES WITH YOU!!"
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-'24 X5MC,'22 430i
-'09 Busa,'05 GSXR-1K(GT28R turbo)'00 Busa(GT3582)
Gone but not forgotten:
-'22 X3MC,'20 M550i,'18 X2,F30 328xi,'07 E63 AMG (1st W211 63 in the 11s),997 C4S Cab,CLS55 AMG,E55 AMG,C55AMG