Although I’ve been following your work for months, this is the first time I comment to ask you a question about your progressive overload method.
I’ve been stuck with the same weight in side lateral dumbbell raises for a while. I can perform the exercise with perfect form with 10kg (20lb) dumbbells for 10 or more reps. However, when I go up to 12,5kg (25lb) dumbbells I cannot get any rep with good form. Using momentum I am able to go to 7-8 reps at 25lb, but I can’t get any of them with good form.
The second theory is similar and is known as "evolutionary neuroandrogenic (ENA) theory of male aggression".   Testosterone and other androgens have evolved to masculinize a brain in order to be competitive even to the point of risking harm to the person and others. By doing so, individuals with masculinized brains as a result of pre-natal and adult life testosterone and androgens enhance their resource acquiring abilities in order to survive, attract and copulate with mates as much as possible.  The masculinization of the brain is not just mediated by testosterone levels at the adult stage, but also testosterone exposure in the womb as a fetus. Higher pre-natal testosterone indicated by a low digit ratio as well as adult testosterone levels increased risk of fouls or aggression among male players in a soccer game.  Studies have also found higher pre-natal testosterone or lower digit ratio to be correlated with higher aggression in males.     
The subjects consumed L of Beet It ( mmol of nitrate) or the nitrate-depleted beetroot juice placebo ( mmol of nitrate) for six days. They engaged in treadmill exercise and knee extension tests on days four and five. The nitrate-rich beetroot juice significantly raised plasma nitrite concentration and decreased systolic blood pressure by 4% (5 mm Hg) compared with placebo. The nitrate-rich beverage also lowered the oxygen cost of walking by 12% and moderate- and high-intensity running by 7%. The nitrate-rich juice also increased the time to exhaustion during high-intensity running by 15% and during incremental knee extension exercise by 5%.8