To help prevent color transfer, especially when damp, we recommend washing your gear before you head out. This helps rinse off any extra dye from the first round of production.
*Wash it solo or with similar colors for best results.
52g (Size M)
59g (Size L)
- Introduction
- Stay warm where it matters most
- Product story
- Keeping your belly warm
- Review 1
- Report from Hokkaido Yeti
- Review 2
- Form and function
- For high-intensity activity in the cold
- Thermal comparison
- Material
- Polartec Alpha Direct
- Shadow Rip: lightweight, strong, durable
- Size guide
- Notes before use
- Preventing color transfer
- Instructions
- Care instructions
- Repair
Introduction
Stay warm where it matters most
Our Alpha Haramaki is made for late-night and early-morning hikers and runners to help them keep warm when temperatures are low.
The advanced Polartec Alpha Direct offers excellent insulation as well as breathability keeping your belly warm.
The surface uses the same ultralight and breathable Shadow Rip fabric as the UL Shirt to maximize the Polartec Alpha Direct’s functionality, letting the heat escape while protecting the cold air.
*The material has been revised from Pertex Quantum Air to Teijin Shadow Rip since 2022.
Product story
Keeping your belly warm
In the autumn of 2015, when light snow started to fall before daybreak, I was trying to pass through the peak of Mt. Goryutake in the Japanese Northern Alps on a fast-packing hike, with only the bare essentials of gear.
The strong wind penetrated my clothes and almost blew me off the cliff. I was wearing everything I had, but I was still freezing and near hypothermia! I thought it was too dangerous to keep going, and decided to rest until the next morning. As I opened my backpack to get my sleeping bag, I remembered the Minimalist Pad in my pack. I wrapped the pad around my waist and put on my rain jacket. I was still shivering but gradually felt my belly getting warmer and started to walk again.
This experience made me want to create tools and clothing that protect the abdomen, resulting in the Merino Hoody (the old version, Updated 2021) and the Alpha Anorak, but another idea that I came up with at the same time was the Alpha Haramaki.
Illustration: Jerry Ukai
Among many belly bands in the world, our Alpha Haramaki is probably the only item to protect the bellies of active hikers. It is easy to wear and warm, but not too warm.
The best balance of warmth and air-permeability is achieved by the combination of Polartec Alpha Direct, the same insulation used in our Alpha Anoraks, and Shadow Rip, the breathable and windproof fabric newly adopted in 2022.
The Haramaki is great for long-distance overnight races when the weather is bad or when you feel cold, tired, and weak.
What I realized through my experience is the importance of keeping your belly warm: when your belly is cold, you feel slow and dull, but as long as it’s kept warm, you can keep going. In other words, if your belly is kept warm you are warm even if the temperature is cold. With a belly warmer, you can minimize the trouble of putting the jacket on and off during activities.
Hopefully, our Alpha Haramaki will receive more popularity among the runners and hikers who traverse through the mountains in Japan!
Review 1
Report from Hokkaido Yeti
In 2017, Yamatomichi supported Team Hokkaido Yeti as they took on the Petite Trotte à Léon (PTL), one of the most demanding mountain endurance races held around Mont Blanc in Switzerland. During the race, the team tested various Yamatomichi prototypes, including what would become the Alpha Haramaki.
The Ultra-Trail du Mont-Blanc (UTMB), held in the European Alps around Mont Blanc, features five categories of races—PTL being the toughest of them all. Teams of two or three (with at least one UTMB finisher) start the race on Monday at 10:00 PM and must cover roughly 300 km within 138 hours by Sunday at 4:00 PM.
I’ve been wearing Haramaki for over five years and have tried all kinds, but this one really stands out. It’s easy to put on and take off, keeps you impressively warm, blocks the wind, and holds its shape well. Honestly, it’s something I’d recommend without hesitation.
During PTL, I started having stomach issues on the second evening, and aside from quick showers at life bases, I kept the Haramaki on the whole way through.
Out on the move, it actually felt warmer and more wind-resistant around the core than the Merino Hoodie. It fit so well under my pack that I barely noticed it was there—and even with all the sweating, there was no chafing or skin irritation. I wore it straight through to the finish.
PTL 2017 finisher / Trail runner
A mountain climber, ski mountaineer, and company employee, Hiroki discovered trail running while actively exploring the mountains and backcountry skiing. He now incorporates ultralight hiking and trail running into long-distance treks and mountain journeys. Hiroki has completed a number of grueling ultramarathons and mountain endurance races, including TJAR 2014, PTL 2015, TJAR 2016, and PTL 2017.
I didn’t use the Alpha Haramaki on the first day since I had packed it in my drop bag, but from the second night on, I wore it every time I slept—and from the third day, I had it on during all the night-to-morning sections. I was honestly surprised by how much of a difference it made in keeping me warm.
In past long races, I’ve often struggled with stomach issues, and keeping my core warm has always been a challenge. But during PTL, I had no problems at all. That’s when I really felt just how effective the Haramaki is—keeping your midsection warm makes a bigger difference than I’d realized.
Pairing it with the Merino Henley Neck T-Shirt was super comfortable. I love how relaxed the Henley feels, but it can let a bit of cold air sneak in around the stomach. Wearing the Haramaki over it solved that completely.
In other 100-mile races, I’ve used Haramaki from different brands, but they’d often slide down or just end up feeling like extra weight. Not this one. The Alpha Haramaki stayed put the whole time—so much so that I’d forget I was even wearing it until I changed shirts. Totally stress-free.
PTL 2017 finisher / Trail runner
A public servant by profession, Kotaro was active in soccer and long-distance track during his school years. After a 10-year break from running, he returned to the trail, inspired by memories of the joy he once found running in the mountains. Since then, he’s taken on numerous races—primarily 100-mile ultramarathons—both in Japan and abroad, while also exploring the mountains on his own two feet, embracing the spirit of long-distance journeys.
I started wearing the Alpha Haramaki from the very first night of PTL, and by the fourth day, I was also using it during nighttime sections on the move.
I don’t usually wear a haramaki, but this experience really showed me how important it is to keep your core warm. It wasn’t just the physical warmth—it also gave me a real sense of comfort and peace of mind.
The Velcro adjustment made it easy to dial in the fit—no tightness, no fuss—and it stayed super comfortable the whole time. It wasn’t just helpful for this kind of race either. I can see it being great paired with a heat pack for cold-weather mountain adventures.
It’s definitely coming with me on future trips—and I’ve already started recommending it to friends and teammates.
PTL 2017 finisher / Trail runner
A professional nurse, Takatoshi first discovered trail running as part of boxing training—but quickly fell in love with the mountains. He now actively explores long-distance trekking routes, ultralight hiking, backcountry snowboarding, and ski touring.
Review 2
During development, we had the opportunity to work with a number of runners and mountain endurance racers, who tested prototypes of the Alpha Haramaki under real race conditions.
In overnight races, it’s pretty common for your core to get cold—even when the rest of your body feels overheated from running. That chill around your stomach can easily lead to GI issues, which is one of the main reasons runners end up dropping out.
What really stood out to me about the Alpha Haramaki was how well it handled moisture. Even when my shirt was soaked with sweat, the inside of the Haramaki stayed dry and warm. It consistently kept my core a few degrees warmer than the rest of my body.
And it’s not too warm either—that balance is what makes it perfect for the ups and downs of trail running. Once your stomach gets cold, it’s hard to bounce back, so putting it on before the sun goes down is the best way to stay ahead of it.
Trail runner
While working as a game director by profession, Makoto also developed one of the world’s lightest carbon trekking poles, Runblur. As a dedicated ultrarunner, he has completed numerous 100-mile races, including UTMB and UTMF.
In recent years, he has become passionate about navigation-based mountain activities, and now spends much of his time darting through the brush at events like the OMM (Original Mountain Marathon).
I wore the Alpha Haramaki during the Koumi 100 Mile, a brutal race made up of five laps on a 32 km course. On the third lap, just as the nighttime section began, I changed into a long-sleeve shirt—but forgot to put the Haramaki back on. Not long after, I started having stomach issues.
The temperature wasn’t even that low, but cold sweat can sneak up on you, and that small mistake ended up costing me.
By the fifth lap, I started wearing the Haramaki over my T-shirt, and that worked perfectly—no slipping, no forgetting, just solid, consistent support.
What really impressed me was that it didn’t just keep me warm—it also helped stabilize my stomach through all the vertical movement. I could really feel how much it protected my core.
Trail runner
Mizue works in import and supply chain management. After raising her children, she took up trail running at a friend’s suggestion—and was quickly drawn into the joy of running through nature.
She now participates in 100K and longer races several times a year, both in Japan and abroad, often combining them with travel. In 2017 alone, she completed the UTA 100K (Australia), UTMB 100M, OSJ Koumi 100M, and Formosa Trail 100K (Taiwan).
What I really like—beyond the warmth and easy layering—is how the Alpha Haramaki supports your core when you're worn out and your abdominal pressure starts to drop. It keeps you more connected to your body and aware of how you're moving.
The Velcro adjustment is great too. It keeps everything in place, even when you're on the move, and over long efforts, I’ve noticed it really helps take the edge off fatigue.
And the pocket is surprisingly useful—perfect for keeping a smartphone warm (since batteries drop fast in the cold) or softening up trail snacks like Trail Butter that tend to harden in low temps. Definitely a smart touch.
Trail runner
A user interface designer, Masaaki works on UI design for consumer electronics and industrial equipment. Passionate about mountain activities like trail running, he actively engages in MYOG (Make Your Own Gear)—creating everything from huaraches and gaiters to metronome apps, blending both analog and digital tools.
He also explores training methods using sensors and cameras for movement analysis and performance tracking.
Form and function
For high-intensity activity in the cold
The Alpha Haramaki is a belly band that has been developed for use during intense activity in cold circumstances, such as ridges with strong winds, snowy mountains, early mornings, and late nights.
Polartec Alpha Direct (136g/m2), which combines excellent heat insulation with good breathability, effectively repels moisture, even during high-intensity activity. The large velcro strips make it easy to put on and take off and keep the Haramaki snug while worn.
If it is difficult to wear, at first, fasten the Velcro at the front and then switch the front and back.
Convenient front pocket for snacks and heat packs.
When worn like in the photo, it warms the lower abdomen.
When worn upside down, the upper belly will be kept warm.
Thermal comparison
Although it is not as warm as 1000 fill power down, the slightly thick Polartec Alpha Direct (136g/m2) used in the Alpha Vest is one of the best insulators available. The Alpha Vest can be used not only in action but also when resting, always keeping you warm.
Comparative test
The below chart compares the 1000 fill power down and other insulators used in thermal clothes on the market.
- Heat retention is measured by JIS L1096A method, in Yamatomichi in-house test. The heat insulation property is measured from the amount of energy consumed by the heat-generating element to maintain its temperature. The maximum value is 100%.
- The values of Polartec and Primaloft fabrics are the manufacturers’ catalog specs. Other fabrics’ values are measured by Yamatomichi. 1000 fill power down includes its 7 denier nylon outer and lining.
Material
Polartec Alpha Direct
- Excellent air-permeability and thermal performance
- Outstanding lightness and packability
- Polygiene treatment for semi-permanent antibacterial and odor-control
Conventional natural down and synthetic insulators tend to contain body moisture within the clothes and as a result, can be quite stuffy. Polartec Alpha Direct, on the other hand, is so air-permeable that it can be worn even during a high level of physical activity.
Additionally, the material itself is treated with Polygiene, which safely inhibits the growth of microorganisms and bacteria by incorporating low concentrations of silver ions. As a result, it possesses antimicrobial and odor-resistant capabilities that far exceed the lifespan of regular clothing.
It is like a fleece with longer puffy hairs.
Shadow Rip: lightweight, strong, durable
The mountain environment can be harsh; the weather is often unstable, temperature changes drastically, the wind is strong and the sunlight is intense. In these situations, it is necessary for the outdoor shirt to achieve both a high level of breathability and windproof performance at the same time. Our newly-adopted Teijin’s Shadow Rip fabric is breathable yet windproof while being light and strong.
Usually, thin and light fabrics have a ripstop structure, in which thick yarns are interwoven in a grid pattern in order to enhance tear resistance. This structure, however, often creates an unsmooth surface, causing the pilling due to weak wear resistance.
Shadow Rip is woven with fine, highly strong yarn to achieve a smooth appearance, and offers excellent resistance to snagging and abrasion while being light and strong. It is also wrinkle-proof and pilling-proof, featuring a soft texture.
Size guide
Product dimensions
Unit: cm
| Size | S | M | L |
|---|---|---|---|
| Full Length | 68~81 | 79~92 | 90~103 |
| Width | 19 | 20 | 21 |
Fitting
Oji 176cm 60kg
Size M (Navy)
Chihiro 168cm 55kg
Size M (Tangerine)
Notes before use
Preventing color transfer
Before your first use, we recommend giving this item a wash to help rinse out any extra dye from production.
If left unwashed and wet, it may cause color transfer when in contact with white or light-colored clothing for long periods—especially out on the trail or after heavy activity.
*Wash it solo or with similar colors to be safe.
Instructions
Care instructions
- Use neutral detergent. Machine wash below 30°C.
- Fasten zipper and velcros, and wash separately or use a laundry net bag.
- Do not bleach and do not use fabric softener.
- Wring gently. Line dry in the shade.
- Do not tumble dry.
- Do not iron. Do not dry-clean.
- If necessary, wash to remove fuzz from the fabric before first use.
Care instructions page
For detailed tips on how to wash, store, and take care of your gear, visit our Care Instructions page.
Payment
- We only accept payment by credit card. We currently do not accept payment via bank transfer from overseas accounts.
- We accept the following Credit Cards: Visa, Master, American Express, and JCB.
- To download your receipt, please click the link included in the Dispatch Notice, which we will send by email as soon as the items are dispatched.
- Bank transfer is only availble for those that own a Japanese bank account.
Delivery
- Order Confirmation will be sent after the order.
- The items will be dispatched within 3 days after the payment is confirmed.
- The dispatch notice will be sent by email as soon as the items are dispatched.
- The delivery may be delayed by unforeseeable reasons such as natural disasters and other logistics issues. We appreciate your patience and understanding.
- We cannot ship multiple orders in one package due to how our delivery system is currently set up.
- We will ship to regions in North America, Oceania, and Europe (excluding Russia) via DHL. For regions in Asia, the Middle East, Central and South America, Africa, and Russia, we use EMS (International Express Mail Service) for shipping.
- Shipping fees and delivery times vary depending on the shipping destination as well as the size and weight of the items.
Size exchange
- Overseas customers who need to change the size of their order, should note that the time needed for shipping will vary greatly depending on your country of residence.
- We only accept exchanges when the item is unused (except for fitting).
- If you wish to exchange the size of the item, please contact us within seven days of receiving your order.
- Exchanges can only be made for the same color in a different size.
- If the size you wish is out of stock, we will suggest a different color.
- If the product is out of stock, we may simply have to ship the item back to you.
- All shipping costs to be carried by the customer.
- We will only send the exchanged item to you, upon receipt of return shipping cost via PayPal.
- Please be aware that some countries charge customs duties depending on the price of the item.
- We are unable to answer any questions on local customs. Please contact your local customs bureau.
Repair
We accept repairs for all of our Yamatomichi products. For inquiries on repair services including patching the holes, repairing with extra components, or fixing the items damaged over time, please feel free to contact us from the “Repair” section of the SUPPORT page.