If you're eating lots of steak and eggs etc, my understanding is that the body makes testosterone from cholesterol and saturated fats. If these are readily available, the double whammy of abundant raw materials and the weight training stimulus could well boost T levels. Don't worry about heart disease, according to Dr. Rhonda Patrick on the Joe Rogan Podcast, heart disease is mostly caused by inflammatory chemicals, so things like smoking, stress, and refined sugar.