The holiday season is a time for joy, celebration, and relaxation. Extra portions of family time, hearty meals, and (frustratingly) long hours in a car seat or airport are all hallmarks of the early winter months. If you’re an avid gymgoer, balancing the festivities with your training can easily add unwanted stress to what ought to be a stress-free period (prickly familial debates at the dinner table notwithstanding).  Luckily, there are more than a few good ways to put your fitness on cruise control during Thanksgiving. You don’t have to consign your gains to melt away just because you’re hitting the road for a family reunion or want to dig into…