How To Choose Running Clothes?

There's something I notice almost every week, whether I'm out on the trails or helping customers in the store: most recreational runners pay a lot of attention to their shoes, and almost none to their clothing. Yet wearing the wrong outfit can turn a great run into 45 minutes of misery — chafing, overheating, or chills from the very first kilometre.

Choosing the right running clothes isn't complicated. But it does require knowing a few key principles. Here's what I've learned after years of racing, training, and conversations with thousands of runners.

For a long time, the rule in the running world was simple: ditch cotton, go synthetic. And there's real logic behind it — cotton absorbs sweat and holds it against your skin, which can cause discomfort, chafing, and in a Quebec winter, dangerous heat loss.

But the reality of the market in 2025 is more nuanced. Brands like Brooks have brought cotton — and especially cotton blends — back to the heart of their collections. And for good reason: the feel is unmatched, the style is there, and for easy runs in mild conditions, it works just fine.

Here's how to think about it in practice:

• A cotton or cotton-blend t-shirt works perfectly for a 30–45 minute run in mild weather (15°C and above) at moderate intensity. That covers the majority of recreational runners who run 2–3 times a week.
• Pure synthetic remains superior for long efforts, intense sessions where you sweat heavily, and especially as the temperature drops. Wet from the cold, cotton chills you far faster than a technical fabric.
• Modern blends (cotton + polyester or modal) are often the best compromise: better feel than pure synthetic, better moisture management than classic cotton.

The guiding principle: the longer, more intense, or colder your run, the more you benefit from a technical fabric. For a relaxed Tuesday evening run in summer, your favourite t-shirt will do just fine.

The biggest mistake I see recreational runners make? Dressing for the season rather than for actual conditions. In May in Montreal, temperatures can swing from 5°C to 22°C within a few days. The solution isn't having a different wardrobe for every situation — it's understanding the layering system.

The three-layer system

Base layer (next to skin)Its sole job: wick moisture away. It should be fitted, lightweight, and breathable. This layer determines your baseline comfort regardless of temperature. In summer, it can be all you need. In winter, it's the foundation for everything else.

Mid layer (insulation)It traps the heat your body generates. It's not always necessary — only when temperatures drop below about 5°C. A lightweight technical fleece or a mid-layer vest is enough in most cases.

Outer layer (protection)Windbreaker, light waterproof, or running jacket. Its job is to protect you from the elements — rain, wind, light snow — without suffocating you. Ideally, it's breathable and can be easily tied around your waist if you get warm.

Summer (15°C and above)

A short-sleeve technical t-shirt or tank top, and a light short or tight. That's it. The classic mistake here is overdressing because it's "only" 18°C at the start. Your body generates enormous heat while running — factor in about 10°C of perceived warmth during effort.

Spring/Fall (5 to 15°C)

The grey zone — and the trickiest to dress for. Generally: a long-sleeve base layer, and depending on the wind, a light jacket. Bare arms are a frequent mistake at 8°C — you think you'll warm up, but you're cold for the first 20 minutes.

Quebec winter (-5°C to 5°C)

This is where layering becomes non-negotiable. Thermal base layer, mid layer if needed, windproof or water-resistant jacket. Add light gloves and a neck gaiter or light toque once temperatures dip below zero. Your hands and ears get cold well before the rest of your body.

Deep cold (-10°C and below)

Running in extreme cold is possible — and often stunning — but it demands discipline. Thermal base layer (merino wool or high-performance synthetic), mid layer, windproof jacket. Add mittens or technical gloves, and protect your face with a balaclava or face cover if the wind is up. Avoid overheating — if you're too warm, you'll soak your layers, and the last 20 minutes of your run will be miserable.

T-shirt or tank top

The key criteria: moisture wicking and freedom of movement. For summer, a relaxed or semi-fitted cut is often more comfortable than a compression fit. Watch out for seams at the shoulders and under the arms — that's where chafing starts after 30 minutes. The core technology is widely accessible at this price point; no need to go premium here. Our t-shirts and tanks for women and for men cover a wide range of fabrics and fits.

Shorts or tights

A matter of personal preference and temperature. Tights are more effective below 10°C to keep joints warm. Shorts with a built-in liner reduce inner thigh chafing — a detail that makes a real difference on longer runs. Our shorts for women and for men, as well as our leggings for women and for men.

Running jacket

The most versatile piece in your running wardrobe — and the one where investing more pays off the most. A good jacket covers a 15°C temperature range depending on what you layer underneath, and it lasts for years. Look for: lightweight construction, breathability, and ideally waterproofing if you don't want rain to hold you back. In Quebec, this is the piece that will let you run in any conditions. Our jackets for women and for men are selected to handle everything.

Winter base layers

This is where fabric quality is most noticeable. Good merino or high-performance synthetic keeps you warmer, dries faster, and stays comfortable on long efforts in deep cold. Unlike a summer t-shirt, this is a piece where spending more makes a concrete difference. Our base layers for women and men are chosen specifically for Quebec winters.

Sports bra

The most underestimated piece of women's running gear. An ill-fitting bra is a major source of discomfort and can genuinely put you off running. The right support level depends on your body type and effort intensity — this is a piece where the investment pays off on every single run. Our running bra selection covers a range of support levels.

Running socks — the most underrated piece of all

This is my strongest conviction, the one I repeat to every runner who comes through Boréal Running: running socks are the single best-value purchase you can make in running gear.

Why? Because the majority of blisters, hot spots, and foot discomfort don't come from your shoes — they come from your socks. A technical running sock:

• Wicks moisture away (unlike cotton, which absorbs it)
• Provides targeted cushioning at pressure points (heel, forefoot)
• Reduces friction with flat or seamless construction
• Holds its shape wash after wash

Athletic socks from big box stores look like running socks, but they're not. You'll feel the difference within the first kilometre. Brands like 2XU, CEP, and Smartwool make socks built specifically for running — it's a $20–$30 investment that genuinely changes the experience. Our socks for women and for men are available in multiple thicknesses by season.

• What temperature will I mainly be wearing this in? That's the most important filter.

• Do I run early in the morning or midday? Perceived temperature can vary by 5 to 8°C depending on the time of day.

• Do I sweat a lot? If so, prioritize highly breathable fabrics and less fitted cuts.

• How sensitive am I to chafing? If you've had irritation before, pay close attention to seam placement and fit.

• Do I run in tough conditions (rain, snow, wind)? If so, a light waterproof jacket isn't a luxury.

Choosing your running clothes is really about learning to dress for actual conditions rather than the season on the calendar. The three-layer system gives you the flexibility to run comfortably from -15°C to 25°C. And if you can only make one investment right now: start with the socks.

Running comfortably means running more often. And running more often means getting better.