The 4-Hour Body - An Uncommon Guide to Rapid Fat-Loss, Incredible Sex, and Becoming Superhuman - Timothy Ferriss
for heat production through shivering. This same shivering could be su cient to recruit GLUT-4
to the surface of muscle cells, contributing to increased lean muscle gain.
2. Even at shorter durations, cold exposure with shivering could increase adiponectin levels and
glucose uptake by muscle tissue. This effect could persist long after the cold exposure ends.
3. In the absence of shivering, it is still possible to capitalize on "fat-burning fat" through the
stimulation of BAT thermogenesis. Curiously, even without shivering, there are small but
unaccounted increases in lean muscle tissue when comparing underwater (superior) vs. land-
based exercise.
4. Cold water improves immunity. Acute cold exposure has immunostimulating e ects, and
preheating with physical exercise or a warm shower can enhance this response. Increases in
levels of circulating norepinephrine may account for this.
5. Not germane to fat-loss, but another reason to use cold exposure: cold showers are an
annaabi.ee 
