MD, MPH here. Those veins are vericose veins, and result from 3 different mechanisms. Most common is 'incompetent valves.' Most commom this is idiopathic, however, in BBers it is usually a result of the constant valsa manuvers of lifting (like pushing the weight up) with causes tremendous build-up on the venous side, damages the valves that veins have. With damaged valves, blood drains backwards and thus creates huge-dilated veins. I would say this is common in BBers, look at Gunter's inner leg, Dillets chest,,,,and even could lead to picture of Mike M with his CHF (long maybe, his CHF most likely ischemic induced), or Arnold with his aortic valve--(which he stated was congenital by the way
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