I do a lot of lifting and read a lot of the bodybuilding forums, including Will Brink's site,
www.bodybuilding.com, Eric Cressey's site, and many others. This notion has been continually debunked, but hard core lifters will often stick with whey on the theory that even a small drop in their ratios (T/E) is not acceptable. I've been drinking soy milk-about half-gallon a week-for over 10 years. I see no significant loss of muscle mass other than that attributable to age. I benched 235 x 5 as my max bench last week, so I wouldn't say I've become totally pussified yet at the tender age of 65.
Frankly, there is so much nonsense in the bodybuilding community and so many bad practices I'm surprised more of them haven't keeled over.
Meanwhile, if you are older and want to kick up your testosterone, order some anastrozole from one of the online pharmacies and join the parade. (NB: I'm not taking it and am just kidding.) There's a new study out suggesting it raises testosterone in older men by surpressing estradiol.
The best way to raise your testosterone is:
1. Eat right. Cut out the shit food, including sugar and high glycemic carbs. Eat enough high quality protein.
2. Stop smoking. Smoking kills testosterone eventually.
3. Lift HEAVY and lift at least 3-4 days a week.
-Robert