TENCEL fibers breathe better and release moisture faster than cotton, which means a cooler, drier feel throughout the day. Cotton is more familiar and durable but holds onto sweat longer. The gap shows up most in warm conditions or after exercise.
What TENCEL actually is
TENCEL is a brand name covering two fiber types: MicroModal and Lyocell. Both are derived from wood pulp using a closed-loop process that recaptures most of the solvent used in production. The result is a fiber that's soft, lightweight, and naturally breathable. It isn't a synthetic, and it isn't conventional cotton. It sits in its own category.
How the fabrics compare
| Property | TENCEL (MicroModal / Lyocell) | Standard Cotton |
|---|---|---|
| Moisture wicking | Fast, releases moisture readily | Absorbs well, releases slowly |
| Softness | Very soft, stays soft after washing | Soft initially, can stiffen |
| Breathability | High | Moderate |
| Feel when wet | Dries quickly, less clammy | Stays damp longer |
| Durability | Good with gentle care | Very durable, machine-wash easy |
| Source | Wood pulp (renewable) | Cotton plant (water-intensive crop) |
Why the moisture difference matters in practice
Cotton absorbs sweat readily, which feels fine at first. The problem is that it holds onto that moisture. In warm conditions, a damp cotton layer sits against skin and traps heat. TENCEL fibers move moisture away from the surface and release it faster, which keeps the microclimate between fabric and skin cooler and drier. [1]
For everyday wear this gap is minor. In heat, after a workout, or during a sauna session, it becomes noticeable. Research on garment fit and scrotal thermoregulation notes that fabric choice and construction both influence local temperature in that area. [2]
What cotton still does well
- Holds up to frequent, hot machine washing without special care
- Widely available at every price point
- Familiar feel that most men have worn their whole lives
- No risk of pilling if you're rough with laundry
If you're not in heat regularly and comfort in warm conditions isn't a priority, cotton is a perfectly reasonable choice. TENCEL earns its premium in the specific conditions where breathability and moisture release actually matter.
Oakman launches Fall 2026. Founding members get first access and founding pricing locked in. Reserve your spot.
Where Oakman fits
Oakman is built specifically for active men looking for scrotal cooling all day and want the option of a cold pack for cooling in the sauna or after heat exposure. The fabric is TENCEL MicroModal, naturally derived from wood pulp rather than plastic, blended with ROICA V550, a clean Japanese stretch fiber, rather than conventional spandex. The fit is athletic with a gusset, an extra panel that gives the testicles room and airflow. Dyes are bluesign approved, so what touches your skin is controlled all the way through the supply chain.
Sourcing is controlled through the supply chain: Oakman uses only bluesign approved dyes, so what touches your skin is managed all the way through. If you're the kind of person who thinks about what goes into the things closest to your body, the Founding 100 get first access when the brand launches in Fall 2026.
Related reading
- Finnish Sauna vs. Infrared Sauna: What's the Real Difference?
- Sauna vs. Steam Room: Which Is Better for Your Health?
Related reading
Frequently asked questions
Is TENCEL underwear actually cooler than cotton?
In warm or active conditions, yes. TENCEL fibers release moisture faster than cotton, which keeps the fabric from sitting damp against skin. Cotton absorbs well but holds onto sweat, which traps heat longer.
Does underwear fabric affect scrotal temperature?
Fabric and fit both influence local temperature in that area. Research on garment construction and scrotal thermoregulation confirms that tighter, less breathable materials tend to raise local temperature compared to looser, more breathable options. [2]
Does scrotal temperature affect sperm quality?
Studies consistently link elevated scrotal temperature to lower sperm quality. [3] Spermatogenesis is temperature-dependent and works best when that area sits a few degrees below core body temperature. [4]
How does TENCEL hold up compared to synthetic performance fabrics?
Synthetics like polyester wick moisture fast but can trap odor and feel less soft against skin. TENCEL matches or exceeds synthetics on breathability while feeling closer to natural fiber against skin. It's a different trade-off than cotton, not a worse one.
Is TENCEL underwear worth the higher price?
It depends on how you use it. For everyday low-activity wear, cotton is fine. If you're active, run warm, or spend time in heat, the breathability and moisture-release difference is real enough to justify the cost.
This article is for general educational purposes and is not medical advice. If you have specific concerns about fertility or your health, talk to a qualified clinician.
References
- Comparative Assessment of Sensory Comfort Properties Across Eco-Friendly Textile Materials for Apparel. 2025. Journal of Natural Fibers (Taylor & Francis). [Link]
- Zleczewski, et al.. (2024). Garment fit, scrotal thermoregulation, and male fertility outcomes: a narrative review. Translational Andrology and Urology. [Link]
- Durairajanayagam D, Agarwal A, Ong C. (2015). Causes, effects and molecular mechanisms of testicular heat stress. Reproductive BioMedicine Online. [Link]
- Durairajanayagam D, Agarwal A, Ong C. (2015). Causes, effects and molecular mechanisms of testicular heat stress. Reproductive BioMedicine Online. [Link]
