What Happens in December Doesn't Stay in December

Why What You Do Between Christmas and New Year Matters More Than What You Do Between New Year and Christmas

There is a paradox embedded in the final weeks of December that few professionals fully appreciate. This period that supposedly designed for rest, reflection, and renewal, frequently becomes the very mechanism through which we undermine everything we've worked to build throughout the year.

The research is clear, yet routinely ignored. And for those of you who have spent years feeling stuck unsatisfied with your health, physique, mindset, and career progression, watching others advance while you remain in place, these weeks represent something far more significant than a mere holiday break. They represent a choice point, one that will either set the foundation for breakthrough in 2026 or perpetuate another year of the same frustrating stagnation.

Allow me to present both the uncomfortable truth and the extraordinary opportunity that lies before you.

The Research: What Actually Happens During the Holidays

Let us dispense with mythology. The widely circulated claim that people gain 5-10 pounds over the holidays is largely unfounded. The actual research, published in The New England Journal of Medicine and corroborated across multiple international studies, reveals a more modest average gain of 0.4 to 1.0 kilograms.

However, before you exhale with relief, consider the more subtle finding: half of that weight is never lost. Studies tracking participants from the United States, Germany, and Japan found that while approximately half of holiday weight gain dissipates by summer, the remainder persists indefinitely. A single kilogram retained annually compounds into 10 kilograms over a decade and with that the slow, invisible erosion of your physical presence and vitality.

But weight represents merely the most visible dimension of holiday damage. The psychological and cognitive costs run deeper.

The Mental Health Paradox

A 2023 survey by the American Psychological Association found that 89% of adults experience elevated stress during the holiday season, with 41% reporting higher stress levels than any other period of the year. The National Alliance on Mental Illness reports that 64% of individuals with existing mental health challenges experience symptom worsening around the holidays.

The sources are predictable yet persistently unaddressed: financial pressure, family dynamics, grief, social comparison, and the odd cognitive dissonance of feeling obligated to demonstrate joy while experiencing its opposite.

Research from the 1980s through the present identifies the same recurring themes in holiday depression: loneliness, anxiety, and helplessness, often intensified by the belief that everyone else is experiencing the happiness we feel we lack.

The Sedentary Spiral

Studies on movement behavior during vacations reveal a troubling pattern: moderate-to-vigorous physical activity decreases while sedentary time increases. Research on children during summer holidays found physical activity dropping by 18% while inactivity rose by 5.5%. Adult patterns mirror this trajectory.

The physiological consequences are immediate. Sedentary behavior reduces lipoprotein lipase activity, impairs glucose metabolism, and diminishes insulin sensitivity. Meta-analyses indicate that mortality risk increases by 2% for every seated hour, rising to 8% per hour when consecutive sitting exceeds eight hours daily.

This is not abstract population health data. This is your body, your cognition, your presence, your capacity to perform when January demands your best.

The Self-Regulation Collapse

Cognitive neuroscience research has identified the precise conditions under which self-control fails: negative moods, minor indulgences that escalate into full binges, overwhelming immediate temptations, and impaired control following alcohol consumption or effort depletion.

The holiday season systematically creates each of these conditions simultaneously.

Researchers have documented what they named the "What the Hell Effect”, the phenomenon whereby a single dietary transgression triggers complete abandonment of self-regulation. The logic runs as follows: "I've already violated my commitment with this cookie, so I might as well consume the entire box." Studies on New Year's resolutions reveal that only half of participants maintain their commitments for even a month, illustrating the well-documented gap between intentions and behavior.

When we recognize the dissonance between who we aspire to be and how we actually behave, we face a choice: change the behavior or change our aspirations. Too often, the holidays become the period where we silently lower our standards, accommodating our failures rather than addressing them.

The Opportunity Obscured: What Recovery Research Actually Reveals

Here is what makes this particularly tragic: the same research that documents holiday damage also reveals the extraordinary potential of this period when approached intentionally.

A comprehensive review in the Annual Review of Organizational Psychology synthesizing decades of recovery research found that time away from work, when used properly, sustains employee well-being, motivation, and job performance. A meta-analysis of 198 empirical samples confirmed positive relationships between employee recovery and resources, well-being, and subsequent performance.

The operative phrase is when used properly.

The Four Recovery Experiences

Research by Sabine Sonnentag and colleagues identified four essential recovery experiences that distinguish restorative time from merely empty time:

1. Psychological Detachment: Genuinely disengaging from work-related thoughts and gaining mental distance. Employees who experience true detachment report higher life satisfaction and fewer symptoms of psychological strain, without sacrificing engagement when they return.

2. Relaxation: The experience of low sympathetic activation, achieved through meditation, breathing practices, or calming activities that allow the nervous system to reset.

3. Mastery: The experience of growth through successfully meeting challenges and undergoing learning experiences outside your professional domain.

4. Control: The sense of autonomy over how you spend your time, a factor significantly diminished when holiday obligations subsume personal choice.

Research has demonstrated that profiles combining high psychological detachment, relaxation, and control predict better sleep quality and reduced exhaustion. An Ernst & Young internal study found that for each additional 10 hours of vacation employees took, their year-end performance ratings improved by 8%.

The tragedy is not that we take time off. The tragedy is that we squander it in ways that leave us more depleted than when we began.

The Decision Point: What Kind of January Do You Want?

If you have reached this point in the article, you likely recognize yourself in these patterns. You've experienced the post-holiday malaise, the January where you feel heavier, slower, more disconnected from your ambitions than you did in November. You've made resolutions that evaporated before February.

Perhaps you've been at mid-management for years, watching colleagues advance while you remain stationary. Your confidence has eroded from extended stagnation. You've let your health decline, carrying extra weight that doesn't match the leader you aspire to become.

This is not a moral failing. This is what happens when intelligent, ambitious people lack a system for intentional recovery and development.

The question before you is simple: Will the weeks ahead be yet another cycle of indulgence followed by regret? Or will they become the foundation upon which 2026 becomes the year everything changes?

Ten Principles for a Holiday Season That Serves Your Future Self

What follows is not a prescription for self-denial. Joy, connection, celebration, and rest are not merely permitted, they are essential. But there is a profound difference between intentional enjoyment and unconscious indulgence, between strategic recovery and passive deterioration.

These principles allow you to fully embrace the holidays while protecting your future.

1. Establish a Non-Negotiable Morning Protocol

Before the day's demands begin, before family obligations commence, claim the first 30-60 minutes for yourself. This period should include movement (even a brief walk), hydration, and 10 minutes of reflection or planning.

Research on psychological detachment demonstrates that how you start recovery periods determines their quality. By establishing morning sovereignty, you anchor the day in intention rather than reaction. The specific activities matter less than the consistency and the message you send to yourself: I am someone who takes my development seriously, regardless of the calendar.

2. Move Daily, Without Exception

The research is unequivocal: laboratory studies found that individuals who performed a 30-minute session of aerobic exercise were impacted less and recovered faster emotionally from subsequent stressors than those who rested. Regular physical activity enhances stress resilience, improves cognitive flexibility, and elevates mood through neurobiological mechanisms including BDNF (Brain Derived Neurotropic Factor acts as a fertilizer for the brain by supporting neuron growth and connections, especially beneficial for aging and conditions like depression) elevation and serotonergic enhancement (increasing the activity or effects of the neurotransmitter serotonin in the body, particularly in the brain).

This does not require a gym. A 30-minute walk after meals, a bodyweight routine in the living room, or a swim if available, the modality matters less than the consistency. When you maintain physical discipline while others abandon it, you return to January with a metabolic and psychological advantage.

3. Apply the "First Plate" Rule

Holiday eating need not be restrictive to avoid damage. The research on counter-regulatory eating (the "What the Hell Effect") reveals that rigid dietary rules invite transgression and subsequent collapse. Instead, implement a simple principle: take time to mindfully appreciate your first plate of any meal before considering seconds.

Eat what you genuinely want. Taste it fully. Then pause. This creates a decision point rather than an unconscious escalation. Most holiday overconsumption occurs not from the first portion but from the automatic continuation without awareness.

4. Limit Alcohol to Enhancement, Not Escape

The research is nuanced here. Light-to-moderate alcohol intake shows no consistent association with weight gain, while heavy drinking demonstrably impairs metabolism, disrupts sleep quality, and lowers inhibitions around food and other self-regulatory challenges.

The question to ask before each drink: "Am I drinking to enhance this experience or to escape something?" If the latter, alcohol will compound rather than resolve the underlying issue. Set a personal limit before each event, and honor it. Every single act of self-regulation and discipline counts into forging the higher-self.

5. Schedule Genuine Psychological Detachment

Recovery research consistently demonstrates that psychological detachment, truly disengaging from work-related thoughts, predicts reduced exhaustion and improved well-being. Yet the modern professional remains tethered through devices, checking email reflexively, monitoring Slack, maintaining the illusion of indispensability.

Designate specific periods, ideally entire days, where you are genuinely unreachable. Inform colleagues in advance. Set auto-responses. Then honor the boundary. The work will remain. Your capacity to engage with it effectively will not, if you fail to recover.

6. Engage in Mastery Experiences Outside Your Professional Domain

The recovery experience of "mastery" involves successfully meeting challenges in domains separate from work. This might involve learning a new skill, completing a challenging hike, engaging in a creative project, or reading deeply in an unfamiliar field.

Such experiences serve multiple functions: they provide genuine cognitive engagement without professional stress, they remind you of your capacity for growth and learning, and they often generate insights that transfer unexpectedly to your professional challenges.

7. Curate Connection, Don't Just Consume It

Social support represents a fundamental human need, yet holiday gatherings often produce more stress than sustenance. The research on holiday mental health reveals that family dynamics, financial pressure, and social comparison constitute primary stressors.

Be intentional about which connections you prioritize. Seek depth over breadth. Create conditions for genuine conversation rather than performative festivity. And recognize that declining certain obligations may serve your well-being better than resentful attendance.

8. Conduct an Annual Review and Intention Setting

The space between years represents a natural threshold for reflection. Yet most people merely exchange one calendar for another without genuine examination.

Dedicate 2-3 hours during this period to structured reflection: What did you learn this year? Where did you fall short of your aspirations, and what does that reveal about the systems or beliefs that limit you? What specific capabilities, if developed, would most accelerate your trajectory? What must you stop doing to make space for what matters?

Document your conclusions. Intentions that remain unwritten remain uncommitted.

9. Limit Social Media and Comparison Exposure

Research on Fear of Missing Out (FoMO) demonstrates its association with diminished well-being, lower self-esteem, sleep deprivation, and reduced life competency. Holiday periods amplify social comparison as curated images of perfect celebrations flood our feeds.

Recognize that what you observe online represents other people's highlight reels, not their reality. Consider reducing social media consumption during this period, or at minimum, curating your feed to remove accounts that trigger comparison. Your psychological resources are finite; spend them on what serves you.

10. Commit to One Specific Development Investment for January

Vague intentions fail. "I'll get in shape" contains no accountability, no specificity, no mechanism for success. Research on goal-setting consistently demonstrates that implementation intentions, specific plans for when, where, and how, dramatically increase follow-through.

Before the holidays conclude, commit to one concrete development investment that begins in January. Not a general aspiration, but a specific action: enrolling in a particular programme, engaging a coach, joining a defined community of practice.

The research on successful weight maintainers, for example, finds that those who plan ahead for holidays, using specific strategies rather than hoping for willpower, experience significantly less weight gain. The same principle applies to career development. Hope is not a strategy.

If You're Ready to Make 2026 Different

You have read this far because something in these words resonates with your current reality. Perhaps you recognize the pattern of holiday deterioration. Perhaps you see yourself in the description of the mid-career leader who has remained stuck while others advance.

If you've spent years at mid-management, unclear which high-value leadership capabilities will make you truly indispensable, watching your confidence erode from extended stagnation, perhaps letting your health decline while carrying extra weight that doesn't reflect the leader you aspire to become, then the holidays represent not merely a challenge to survive but an opportunity to transform.

Most professional development programmes address one dimension of this challenge. They focus on skills, or on mindset, or on physical presence, as though these exist in isolation. But breakthrough doesn't happen when you fix one piece. It happens when all three align.

THE APEX LEADER PROGRAM™

90-Day Transformation for Mid-Career Leaders Ready to Break Through

Launching February 2026, The APEX Leader Program™ addresses the three interconnected dimensions that determine whether you remain stuck or finally advance:

A : Architect Your Psychology

Using Cognitive Behavioral Therapy and Neuro-Linguistic Programming, we identify and restructure the beliefs that have kept you stuck: "I'm not leadership material," "I'm too old to change," "I've lost my edge." By Week 12, you don't try to be a leader. You are one. The internal shift is complete.

P : Prime Your Vitality

Your physical presence is your leadership presence. We build a commanding physique through progressive strength training and precision nutrition, dropping 12-20+ pounds of fat while developing visible muscle in shoulders, chest, arms, and back. When you look like someone who takes themselves seriously, others take you seriously. By Week 12, you look in the mirror and like what you see.

E : Elevate Your Leadership

We identify and develop the three advanced leadership skills most critical for your specific role and trajectory, from Applied Emotional Intelligence to Executive Presence and Gravitas to Difficult Conversation Management. Through education, practice, and real-world application, these capabilities become not things you're "working on" but who you are.

X : eXpand Your Trajectory

Transformation without positioning is wasted potential. In Weeks 9-12, we shift from building to positioning: LinkedIn optimization, stakeholder mapping, personal brand strategy, and preparation for compensation conversations. You emerge not just transformed, but strategically positioned for executive-level opportunities.

This is not another course you'll abandon by Week 3. This is the integrated system that addresses why you've remained stuck: your psychology, your physical presence, and your skill gaps simultaneously.

The programme launches in February 2026. The holidays represent your opportunity to prepare, to implement the principles above, to complete your annual review, and to enter the programme ready to transform.

If 2026 is the year you finally break through the ceiling that's contained you, the decision begins now, in how you approach these holidays, and in the commitment you make to yourself before the New Year arrives.

Apply for The APEX Leader Program™ today and start by booking a free consultation on the program page.

The holidays will pass regardless. The question is simply who you will be when January arrives, and whether that person is finally ready to become the leader you've always known you could be.

Choose wisely. And enjoy the season.