There is a program that will plot a graph of time versus percentage of THC in your system given the days you've smoked. The non-smoker would have to take in virtually as much second hand smoke, as a smoker. Non-smokers are safe in a ventilated area, as long as they don't get a hair test. According , simply blowing crack smoke on ones hair may cause a positive hair test. The only pot smoke that contains THC is the smoke that hasn't entered the lungs.
Nothing beats proper training taken to an extreme.
A high calorie diet is the next best way to increase metabolism. Consuming mass quantities of high calorie food will increase metabolic rate by up to 10 percent. On the contrary, a malnutritious light diet could lower your metabolism by 10 percent. Unfortunately, labs usually test for speed, and could get you into trouble. So exercise with intensity, and eat big Indica 3.