Product Description
You can't control the weather on race day. But here's what Pros figured out: you can control how your body handles it. While most athletes pray for cooler temps and train in comfort, the Pros are starting to train year-round with intentional heat exposure.
Why? To build an oxygen-carrying and heat management advantage that works in ANY conditions.
The CORE Heat Training Suit is like a portable sauna—a disposable polypropylene suit that turns your indoor trainer or treadmill into a heat chamber.
How Heat Improves Performance
The science is simple: heat stress triggers your body to produce more blood plasma, which then signals production of additional red blood cells. Over a few weeks, your blood's oxygen-carrying capacity increases. Research shows this translates to improvements in VO2max, lactate threshold, and power output—even when racing in cool conditions. Not only that, it teaches your body how to sweat more effectively.
The Heat Suit Advantage
Like An Altitude Camp – Studies show five weeks of heat training (5 sessions per week, 50 minutes each) increases your hemoglobin mass by 3-4%—the same boost you'd get from a three-week altitude camp, but without leaving your house. More hemoglobin means more oxygen delivery to working muscles.
Heat Training for Less Stress – The suit acts as a "portable environmental chamber" that elevates your core body temperature faster with less physical effort. You reach your target "heat strain" without crushing yourself, protecting your training load while maximizing adaptation.
Works Anywhere, Year-Round – No need to wait for summer or travel to hot locations. The suit lets you build heat tolerance on your time, ensuring you're ready when it counts—whether that's Western States in June or your local marathon in August.
Package includes 2 disposable suits (reusable multiple times - rinse and air dry after each use)
How to Use The Heat Suit
Protocol: Wear the suit during easy to moderate intensity training indoors (cycling or running). Start with 3 sessions per week for 30-50 minutes, building to 5 sessions per week. Be patient and progressive.
Timing: Begin 5-6 weeks before your goal race for maximum adaptation.
Pairing: Pair with a CORE temperature sensor to monitor your exact core temp and stay in your optimal heat training zone (typically 38.5-39°C). Hydrate aggressively before, during, and after each session.
Sizing:
S: suitable for people up to ~ 172cm / 5'7"
M: fits most people up to ~ 180cm / 5'11"
L: fits most people 180cm - 195cm / 5'11" - 6'4"
If in doubt about size, we recommend sizing up or contacting us for advice.
Important Safety Information: Heat training carries risks including dehydration, heat exhaustion, and heat stroke. Always train under medical guidance and/or coach supervision.
For gear that arrives damaged or falls under the manufacturer's warranty: Please send a photo of the damage or error message to hello@thefeed.com. We will either help process a claim for the product and a replacement product or store credit will be provided, or we will direct you towards the correct place to make a warranty claim for the product. For returns on gear that you have used, we follow the manufacturer's instructions for satisfaction guarantees. This is specific to each gear product, terms and conditions may change.
CORE Heat Suit FAQ's
Everything you need to know before getting started.
Begin 5-6 weeks before your goal race for maximum adaptation. The physiological changes—increased hemoglobin mass and plasma volume—take 4-5 weeks to fully develop, so timing matters for peak benefits on race day.
Start with 3 sessions per week for 40-50 minutes during easy to moderate training. Build to 5 sessions per week as you adapt. Studies show 5 weekly sessions produce the most significant hemoglobin mass increases.
No! Research shows heat training improves performance in all conditions, not just hot weather. The hemoglobin mass gains boost oxygen delivery whether you're racing in 50°F or 90°F temps.
Yes! Each suit is reusable. Simply rinse it in the shower after each session and let it air dry. With proper care, each suit lasts through multiple training sessions before replacement.
No, but it's highly recommended. The CORE sensor lets you monitor your exact core body temperature to ensure you're training in the optimal heat zone (38.5-39°C) without overdoing it.
When done properly with medical guidance and coach supervision, yes. Always hydrate aggressively, monitor how you feel, and stop immediately if you experience dizziness, nausea, or vomiting. Not recommended for those over 65, pregnant women, or anyone with heart conditions without physician approval.