1. SEX - That's right, Netflix n' Chill will un-swole your gym-game. One poll from 2011 suggests more than half 60 percent of people report they’re more likely to hook up in this season than at other times of the year. Sounds great right!? 'But how is that going to derail my fitness', you ask? Simple, hookups make you lonely, loneliness leads to depressive symptoms, and depressive symptoms are characterized by inactivity, reclusiveness, and negative affect: a 2010 study of 832 college students showed that 26 percent of women and 50 percent of men reported experiencing positive emotions after a one-nighter; conversely, 49 percent of women and 26 percent of men described negative feelings.
...all the pre-workout in Arnie's attic ain't going to get you to the gym when you're caught up in your feelings.
2.SLEEP - You go to holiday parties; you don't sleep. You stay the night at your relative's or friend's; you don't sleep (well). You are planning your vacation, wondering if the gift you bought your girlfriend will make her breakup with you, or regretting your actions at the office Christmas party; you don't sleep. Until you do get a chance to sleep, and then you oversleep. When you stress (always) and don't sleep soundly (always), Cortisone builds up in your body. Studies have shown that excess cortisone levels contribute to fat storage, delay muscle repair and stunt muscle growth.
...no sleep, low sleep, or poor sleep, will turn you into a soggy, deflated, holiday prune; you may as well just go wedge yourself in between the couch cushions until you start to stink.
3. CROSSFIT - nahhh, I'm just kidding...it doesn't start with an S... SAMSONITE (I wasway off!) - Stay with me now. Holidays, for most of us, equals forced family interaction. And because most of us moved as far away from our family as possible, it means that we have to travel to them. Travelling requires you to pack things in travel-receptacles. Samsonite is a brand that manufactures travel receptacles...luggage...to the lay-person. When we travel, it is usually by car or by plane, which means we are sitting for hours on end. Sitting for hours on end munches up your time, your patience, and your posture. Pick whichever one of those you like for an excuse not to workout.
...hence, Crossfit = derailment of your fitness during the holidays.