A study published in Medicine and Science in Sports and Exercise found that protein taken 30 minutes before resistance training gave the metabolism a boost that lasted long after the exercise was over- up to 24 hours later, in fact!
The study was small (eight subjects) but I like that it included both men and women in a double-blind two-trial crossover design. Compared with pre-exercise carbohydrate supplementation and heavy resistance training without supplementation, 20 grams of pre-exercise protein supplementation significantly increased metabolism, as measured by resting energy expenditure (REE).
Protein vs Carbs
Here's the difference: while pre-exercise carbohydrate supplementation raised metabolism as well, pre-exercise protein supplementation outperformed carbs at the 24 hour mark and continued to keep REE elevated.
So taking at least 20 grams of protein, 30 minutes before resistance training, just might keep keep you revved up all day long.
And while we're talking about timing, make sure you are absorbing that supplemental protein properly.
Read how gastrointestinal transit time (GTT) and the rate of protein digestion can affect absorption (hint: so does Aminogen) here. Don't let incomplete protein absorption slow you down!