In summer, keeping your feet comfortable comes down to three things: natural, breathable materials, a sole that insulates from the hot ground, and lightweight shoes that don't retain heat. IKO:NOTT sneakers are designed with certified natural FSC cork, breathable recycled leather, and a memory foam sole, precisely for this purpose.
It's hot. Your feet know it before you do.
It starts subtly.
A slight warmth in the sole. A rubbing sensation you didn't notice in the morning. Feet swelling a little; it's normal, it's the heat.
And then around 3 PM, when the sun is beating down and you still have two hours of walking left, you remember you should have chosen your shoes better.
Summer is the season when we walk the most. And paradoxically, the one when we think about it the least.
What really happens when it's hot
Heat expands. So do feet.
In hot weather, foot volume can increase by 5 to 8% over the course of the day. This is not insignificant: a shoe that fits in the morning can feel tight in the evening. A synthetic sole absorbs heat from the asphalt and radiates it back to the foot. A non-breathable fabric turns every step into a sauna.
It's not a matter of weakness. It's a matter of physics.
Well-equipped, you don't feel it. Poorly equipped, that's all you can think about.
What your shoes should do for you (and don't always do)
1. Insulate from hot ground
Asphalt in summer can exceed 50°C. A good sole insulates, cushions, and reflects as little heat as possible back to the foot.
At IKO:NOTT, we chose FSC-certified natural cork as the main material for our comfort insoles. Cork is a natural thermal insulator; it absorbs shocks without accumulating heat. Result: even on a burning sidewalk, the sole remains at a neutral temperature.
And on the Phoenix model, the outsole incorporates 75% ULVA algae: a biosourced, lightweight material that responds to every step with flexibility.
👉 Discover the Phoenix collection
2. Allow to breathe
Synthetic materials seal. Heat stays inside.
The recycled leather of our sneakers, however, allows air to circulate while protecting against splashes. No plastic mesh that retains sweat. No waterproof coating that confines.
Just a material that ages well, softens with you, and doesn't turn your feet into an oven.
3. Support without constricting
Hot feet move more, swell more, and tire faster.
Our memory foam sole (developed with a podiatrist) conforms to the morphology of each foot. It accompanies movement rather than fixing it. No rigidity, no pressure points. Just constant support, from the first step to the last.
And socks, in all of this?
We know it. In summer, instinct says: no socks.
But with a closed sneaker, socks remain your best ally… provided you choose them well!
A cheap synthetic sock retains heat and moisture. An organic cotton sock, however, absorbs perspiration and allows the skin to breathe.
Our OEKO-TEX certified organic cotton mid-calf socks are designed for exactly that. Lightweight, soft, reinforced at the heel to prevent rubbing during long walks. The detail that changes everything when the kilometers accumulate in the heat.
→ "The less you feel them, the better." That's the brief we gave ourselves.
Three simple habits to take care of your feet (and your sneakers) in summer
Try on your sneakers at the end of the day, not in the morning. Your feet are at their maximum volume in the evening. If they fit well at 6 PM, they'll fit well all day.
Air out your sneakers after each outing. Don't leave them in a bag or closed closet. Cork and leather need air to dry and maintain their shape.
Clean them with a damp sponge, never with too much water. A wipe with a sponge is enough for recycled leather. No need to do more, and it preserves the material much longer.
What we remember
In summer, feet work harder. They deserve better than to be ignored.
A good pair of sneakers for hot weather isn't necessarily the lightest or most ventilated. It's the one that considers all the details together: insulating sole, breathable material, cushioning that lasts all day.
At IKO:NOTT, that's exactly what we tried to do.
→ Discover our summer sneakers
Frequently Asked Questions — foot comfort in hot weather
Why do feet swell in summer?
Heat causes blood vessels to dilate and water retention in tissues, which increases foot volume, sometimes up to 8% by the end of the day. This is why it's recommended to try on shoes in the evening and choose models with a flexible sole and leather that softens with use.
What shoes to wear for long walks in summer?
Opt for lightweight shoes with a cushioning and insulating sole (cork is ideal), an upper made of natural or breathable recycled material, and good support without excessive rigidity. IKO:NOTT sneakers incorporate these three criteria, with a memory foam sole developed with a podiatrist.
Is it necessary to wear socks with sneakers in summer?
Yes, especially during long walks. Organic cotton socks absorb perspiration and reduce friction that causes blisters. Avoid synthetic socks that retain heat. IKO:NOTT mid-calf socks in OEKO-TEX organic cotton, made in Europe, are designed for this purpose.
How to care for recycled leather sneakers in summer?
A damp sponge is enough to clean recycled leather after a summer day. Then air out your sneakers outdoors (never in a confined space!) to let the cork and leather dry naturally. Avoid prolonged direct sunlight, which can dry out the materials.
Are cork sneakers suitable for hot weather?
Yes. Cork is a natural thermal insulator: it does not accumulate heat from the ground and remains at a neutral temperature even on hot asphalt. This is one of the reasons we chose it for IKO:NOTT comfort insoles, FSC certified to guarantee its responsible origin.
Find all our models → iko-nott.com/collections/toutes-les-sneakers
