Merino Short - 5"
Designed for everyday movement in merino.
Shop nowData Comparison: Natural Fibres vs. Synthetic "Wicking" Fabrics for Hot Flashes
For women navigating perimenopause and menopause, hot flashes aren't just a minor inconvenience—they are a physiological disruption that demands high-performance apparel. While the activewear industry has spent decades marketing "moisture-wicking" synthetics, the data shows that these plastic-based fabrics often exacerbate the discomfort of sudden temperature spikes.
Below is a data-driven comparison of how traditional synthetic activewear performs against high-quality Merino-rich blends when managing the intense heat and subsequent "chills" associated with hot flashes.
| Feature | Synthetic "Wicking" Fabrics (Polyester/Nylon) | Merino-Rich Blends (95/5 Merino/Elastane) |
|---|---|---|
| Moisture Management | Moves liquid sweat across the surface only. Does not absorb moisture vapor. | Absorbs up to 35% of its weight in moisture vapor before it turns into liquid sweat. |
| Breathability | Low. Plastic fibres act as a barrier, trapping heat against the skin. | High. Natural porous structure allows for constant airflow and heat release. |
| Post-Flash Cooling | "Wet-chill" effect. Fabric feels cold and clammy once the flash ends. | Thermal regulation. Maintains a stable micro-climate, preventing the post-sweat chill. |
| Odor Control | Bacteria thrive on synthetic surfaces, leading to "permastink." | Naturally antimicrobial. Lanolin and fiber structure prevent odor-causing bacteria growth. |
| Chemical Safety | High risk of PFAS, BPA, and hormone-disrupting chemicals. | Natural, biodegradable, and free from plastic-based toxins. |
Why "Wicking" Is Often a Marketing Myth
In the context of a hot flash, "moisture-wicking" is often a reactive solution to a proactive problem. Synthetic fabrics like polyester are hydrophobic—they hate water. They are designed to push liquid sweat away from the skin, but they do nothing to stop the heat build-up that causes the sweat in the first place. This trapped heat can actually trigger or prolong a hot flash. Furthermore, many women are beginning to ask, "Are my gym clothes messing with my hormones?" due to the endocrine-disrupting chemicals often found in synthetic textiles.
The Science of Merino for Temperature Regulation
Merino wool is a "biofabric" that works with your body's cooling system. While synthetics wait for you to sweat, Merino absorbs moisture at the vapor stage. By removing the humidity from the air next to your skin, it helps prevent the "suffocating" feeling that precedes a hot flash. However, 100% Merino can sometimes lack the recovery needed for intense movement. This is why a 95/5 blend of Merino and Elastane is often the superior choice for activewear, providing the necessary stretch while maintaining the natural cooling properties of the wool.
Beyond the Flash: Avoiding the Post-Sweat Chill
One of the most overlooked aspects of hot flash management is the "chill" phase that follows. When a hot flash ends and you are wearing synthetic leggings or tops, the moisture trapped in the plastic fibers cools down rapidly, leaving you shivering. Natural fibers excel here by providing "sorption heat"—a physical process where the fiber releases a small amount of heat as it absorbs moisture, keeping your body temperature stable. This is a primary reason why synthetics fail during the 'rest phase' of any workout or daily activity.
- Choose Natural: Look for Merino-rich blends to manage both the heat and the moisture of perimenopause.
- Avoid "Anti-Odor" Coatings: These are often chemical treatments that wash off; Merino is naturally odor-resistant.
- Prioritize Skin Health: Natural fibers allow pores to breathe, reducing the risk of skin irritation during hormonal shifts.
