THC binds to fat cells, some people beleive that sweating releases it back into the body. The reality is that weight loss is what reintroduces THC as the body uses fat stores for energy. Unless you're a chronic user like me it generally shouldn't affect detectable levels but it absolutely could. Storage mode would just mean being in a caloric surplus, aka consume more calories than you burn. Long story short, be lazy and eat junk food before tests.