Winter Training: What Actually Changes When It Gets Cold

A practical guide to training through winter: how long to warm up in the cold, how to layer, hydration and protein targets, and when a cold means resting.

Fitness doesn't drop in winter because of the cold — it drops because your session count quietly halves. It's dark at five, it's −5 outside, and suddenly four sessions a week has become one. The cold itself isn't the problem; short warm-ups, bad layering, and a program you wrote in July are. Here's what to change concretely between December and March.

Your warm-up needs to double

In summer five minutes does the job. At 5 °C and below, budget 12–15 minutes before your first working set. Cold muscle gets less blood flow, tendons are stiffer, and the same force lands on tissue that isn't ready to take it.

5–8 minutes of easy cardio (bike, treadmill, skipping rope) until you see sweat on your forehead — the sweat is the signal, not the clock.
Two rounds of dynamic mobility: 10 backward arm circles, 10 walking lunges, 10 cat-camels, 10 bodyweight squats.
Four ramp-up sets instead of two. For a 100 kg working squat: 20 kg × 8, 40 kg × 5, 60 kg × 3, 80 kg × 2, then your working sets.

If you train in a cold garage or an unheated gym, keep the hoodie and long tights on for the first two or three exercises. Strip layers once you're genuinely warm, not the moment you walk in.

Outdoors: three layers, not five

The most common mistake is overdressing. The rule that works: dress for a temperature 10 °C warmer than it actually is, because that's roughly how much you'll warm up in ten minutes of moving. If you feel pleasantly warm at the start, you're overdressed — the first five minutes should feel slightly cold.

Base layer: a thin long-sleeve that moves sweat off the skin. Not cotton — it soaks and stays wet against you.
Mid layer: fleece or a light hoodie, and only below 5 °C.
Outer layer: a windproof shell. A 20 km/h wind at 0 °C feels like −6 °C.
Hat and gloves, always. You lose a disproportionate amount of heat through your head and hands, and fingers are the first thing to stiffen up and lose grip on a bar or poles.

Running in the dark and on ice

On snow and ice, shorten your stride about ten percent and raise your cadence: aim for 170–180 steps per minute instead of your usual 160. A shorter stride puts your foot down under your body rather than ahead of it, which is where slips come from.

Expect to run 15–30 seconds per kilometre slower at the same effort. That's normal and it isn't lost fitness. In winter, run by feel or heart rate, not by pace. Save intervals for clear pavement; on ice, hold a pace where you can talk in full sentences.

If you're debating whether the path is too slippery, it is. A treadmill at 1% incline isn't a defeat — it's 40 minutes you didn't lose.

Winter is the best block for strength

If you have no season or race coming up, use 10–12 weeks of cold weather for an indoor strength block.

3–4 sessions a week, 45–70 minutes each.
Main lifts: 3–5 sets of 3–6 reps at 80–87% of 1RM, resting 2–3 minutes.
Accessories: 3 sets of 8–12 reps, resting 60–90 seconds.
Progression: +2.5 kg per week on upper-body lifts, +5 kg on squat and deadlift, for as long as the reps stay clean.
Every fifth week is lighter: same lifts, 60% of the load, half the sets.

Food and water when you don't feel thirsty

Cold blunts thirst, while you lose water breathing dry air and sweating under your layers. Work from 30–35 ml per kilogram of bodyweight a day — for an 80 kg person that's 2.4–2.8 litres — plus 500–700 ml per hour of training. The check is simple: weigh yourself before and after a session; losing more than 2% of bodyweight means you drank too little.

Keep protein at 1.6–2.2 g per kilogram, so 130–175 g at 80 kg. Warm, calorie-dense food is easier to eat in winter, so if gaining weight isn't the goal, watch liquid calories and evening snacking — that's where 300–600 kcal a day disappears unnoticed.

From October to March at northern latitudes the sun is too weak for your skin to make enough vitamin D. Rather than guessing, get a blood test (25-OH vitamin D) and let a doctor decide whether you need anything and how much.

Colds: the above-the-neck rule

Symptoms above the neck — blocked nose, mild sore throat, sneezing, no fever — mean you can train, but at 50–60% of your usual volume and with nothing taken to failure. Symptoms below the neck — chesty cough, fever above 37.5 °C, body aches, diarrhoea — mean rest.

Coming back after a fever: count 1–2 easy days for every day you ran a temperature. Make the first session 50% of the load and half the sets, then add 10–15% each session after that.

When to see a doctor

Chest pain, pressure or tightness on exertion, especially spreading to an arm or jaw — same day, urgently.
Fever above 38 °C for more than three days, or a cough lasting longer than three weeks.
Wheezing and breathlessness out of proportion to the effort in cold air — this can be exercise-induced asthma.
Fingers or toes that turn white, then blue, and go numb in the cold.
Resting heart rate more than 10 beats above your normal for over a week, together with fatigue and poor sleep.

The short version

In the cold, warm up for 12–15 minutes and do four ramp-up sets instead of two.
Dress for 10 °C warmer than it is; you should feel slightly cold at the start.
On ice, shorten your stride, aim for 170–180 steps per minute, and accept a pace 15–30 s/km slower.
Use winter for a 10–12 week strength block: 3–4 sessions a week, 3–6 reps at 80–87% of 1RM.
Drink 30–35 ml per kg daily; train lighter only for above-the-neck symptoms, and rest for below-the-neck ones.