Why Winter Is the Best Season to Start a Fitness Routine—Backed by Science

Posted November 29, 2025

In Blog, Featured, Fitness Updates, Updates

Most people wait until January to fix their fitness. They white-knuckle their way through the holidays, feel terrible on New Year’s Day, and then try to sprint out of the gate with a plan they don’t even like. But here’s the twist: winter is actually the best season to start getting stronger—and the research backs it up.

Winter gives your body and brain a few surprising advantages that make starting now easier, more enjoyable, and more effective.

Let’s break it down.

1. Your Body Burns More Calories in Colder Months

Your metabolism subtly increases when temperatures drop because your body works harder to maintain internal warmth. A study from the National Institutes of Health found that mild cold exposure activates brown adipose tissue—your body’s “metabolically active” fat—which increases energy expenditure and calorie burn.

Translation:
Your body is naturally primed to burn more calories in winter…you just need to give it the stimulus.

2. People Are More Consistent When They Start Before January

Behavioral psychology shows that habits formed before a major cultural milestone—like New Year’s—tend to stick better. This is tied to the “Fresh Start Effect,” where people feel renewed motivation around temporal landmarks.

But the catch? Starting before the milestone creates momentum. You enter January with a routine already in motion instead of scrambling to build one from scratch.

In other words, December starters win.

3. You Actually Have a Performance Advantage Indoors

While outdoor performance may dip in the cold, indoor training sees the opposite. A study in the Journal of Sports Sciences found that athletes training in cooler conditions showed improved endurance and perceived lower effort during high-intensity exercise.

Inside Strong, where the workouts are structured, coached, and temperature-controlled, your body is in its sweet spot for building strength and conditioning.

4. Mood and Energy Improve Dramatically With Winter Training

Seasonal dips in sunlight can affect mood and motivation. Movement is one of the few interventions proven to counter it. Research shows that exercise increases serotonin, dopamine, and endorphins—chemicals that help regulate mood and energy

The quicker you start moving, the quicker you break the winter slump.

And let’s be honest: Finishing a Strong workout in December hits different. You walk out feeling like you beat the season instead of letting it beat you.

5. You Enter the New Year Already Stronger, Leaner, and More Confident

Starting now gives you a four-to-six-week head start. This changes everything:

You build foundational strength
You improve conditioning
You’re mentally dialed in
You avoid the “holiday regret” cycle
And January becomes a continuation—not a desperate reset

By the time most people are dragging themselves into a gym for the first time all year, you’re already cruising with momentum, confidence, and results.

Why This Matters for You (and How Strong Makes It Easy)

Here’s the reality: momentum is a weapon. If you start training in December, you don’t fight the uphill battle everyone else faces in January.

And right now, Strong is making it easier than ever:

Start Now and Pay Nothing Until January 1.

No payments.
No risk.
Just progress.

Train now—pay later—and walk into the New Year already ahead of the pack.

Your future self is going to be grateful you didn’t wait.

Casey Sergent