Captured when I carried both my heavy tripod and big lens around SF Zoo for a couple hours today and I call that a workout! (Bogen 3046 tripod, 9.2 lbs; Manfrotto 3421 Gimbal Head, 3.1 lbs; Nikon D2x body, 2.7 lbs; Nikon 600mm f4 IF_ED AI 13.9 lbs - total ~ 30 lbs).