Endurance Athletes

Kyrylo — Cyclist & IT Professional

"Within two days, I gained an extra two miles per hour — with no added training. At 42, I feel like I’m back in my 30s in terms of recovery. From month two, both energy and performance climbed dramatically.

But it’s not just physical. My focus at work improved as well. Balancing heavy training with a demanding IT career takes clarity as much as strength. With Pürblack, I can push physically and mentally without burning out.

Four months in, it feels like an exoskeleton for my daily life — stronger output, faster recovery, and no side effects.

I also tracked my sleep with a Garmin bio tracker before and after starting my protocol featuring White Rabbit Serene shilajit resin. The difference was measurable: my Garmin Sleep Score increased 13%, driven by a 22% jump in sleep duration. I moved from a baseline of “Fair” sleep—chronically under-sleeping at around 6 hours—to a “Good” baseline at roughly 7.5 hours. And that matters: it’s not just feeling more rested, it’s the kind of recovery that lets you stack hard training days without digging a deeper hole."

Product Uses:

Shilajit: True Gold, Deja Brew

White Rabbit: Vive, Serene, Slim

Peptides: Muscle+, Joint+

Endurance isn't about a single performance — it's about what your body can handle tomorrow, next week, and during the final hours of a stage race or an ultra. Back-to-back training, long hours on the road or trail, and high mileage all put stress on oxygen delivery, cellular recovery, and immune resilience.

Pürblack's endurance stack is designed for that demand. By pairing natural targeted peptides with advanced shilajit resins, you get smoother circulation, more efficient cellular energy production, and deeper overnight repair. It's how endurance athletes can keep stacking miles, stages, or volume weeks without burning through their reserves.

5 Granted US Patents
5 US Patents
Full In-House Manufacturing
Full In-House Manufacturing
No Lab-Altered Ingredients
No Lab-Altered Ingredients

Built for long days, stage efforts, and steady volume.

Skiing Performance
  • Circulation & oxygenation: smoother pacing during long efforts.

  • Sleep-driven recovery: faster turnarounds between hard days.

Better Sleep
Biking Performance
  • Immune resilience: fewer gaps in heavy training blocks.

  • Joint protection: comfort and durability when weekly hours climb.

Swimming Performance
Research Grade Shilajit Resin
Research Grade Shilajit Resin — Morning

Supports steady energy and oxygen efficiency throughout long sessions. Its rich humic and fulvic acids and 80+ minerals fuel mitochondrial ATP production, giving endurance athletes reliable power without stimulants.

Explore Research Grade
White Rabbit® Serene Shilajit Resin
White Rabbit® Serene Shilajit Resin — Evening

Helps the body wind down, restore balance, and repair overnight. The adaptogenic profile of shilajit combined with calming botanicals promotes deeper sleep and natural hormonal regulation after demanding training days.

Explore Serene
MUSCLE+ Peptide Capsules
MUSCLE+ Peptide Capsules

Accelerates muscle repair and keeps fatigue at bay. These targeted peptides activate genetic pathways for muscle regeneration, helping athletes bounce back faster and maintain lean strength under heavy workloads. NSF Certified for Sport®.

Explore Muscle+
JOINT+ Peptide Capsules
JOINT+ Peptide Capsules

Supports steady energy and oxygen efficiency throughout long sessions. Its rich humic and fulvic acids and 80+ minerals fuel mitochondrial ATP production, giving endurance athletes reliable power without stimulants. NSF Certified for Sport®.

Explore Joint+
Research Grade Shilajit Resin — Morning

Supports steady energy and oxygen efficiency throughout long sessions. Its rich humic and fulvic acids and 80+ minerals fuel mitochondrial ATP production, giving endurance athletes reliable power without stimulants.

Explore Research Grade
White Rabbit® Serene Shilajit Resin — Evening

Helps the body wind down, restore balance, and repair overnight. The adaptogenic profile of shilajit combined with calming botanicals promotes deeper sleep and natural hormonal regulation after demanding training days.

Explore Serene
MUSCLE+ Peptide Capsules

Accelerates muscle repair and keeps fatigue at bay. These targeted peptides activate genetic pathways for muscle regeneration, helping athletes bounce back faster and maintain lean strength under heavy workloads. NSF Certified for Sport®.

Explore Muscle+
JOINT+ Peptide Capsules

Supports steady energy and oxygen efficiency throughout long sessions. Its rich humic and fulvic acids and 80+ minerals fuel mitochondrial ATP production, giving endurance athletes reliable power without stimulants. NSF Certified for Sport®.

Explore Joint+

The Endurance Stack

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FAQ

  • Endurance Athletes
  • Shipping & Orders
  • Subscriptions
  • Return, Refund & Replacements
When will my order be shipped? +

Orders take 1-2 business days to process and are shipped promptly. We do not ship orders during the weekend or during US holidays.

Orders are confirmed when they get a tracking number.

How do I track my order? +

Use our chat box to track your order or get updates directly from your email. Order updates are sent to your registered email and will have a tracking link available.

Where can I find my order number? +

You can find your order number in the order notification sent to you via email.

How much do you charge for shipping? +

All orders shipped to the USA are shipped free.

For overseas orders, order weight and location determine the shipping rates in real time.

You can check for shipping rates by adding the product you like to the cart, then proceed to checkout.

In the checkout, add in your address and allow the page to get real time shipping rates.

UPS, DHL and USPS handle domestic USA shipping and UPS, DHL and USPS for international shipping.

Customs fees and charges are not included in the shipping offer.

At this time, due to custom regulations we are unable to ship to Mexico

Do you cover customs fees and charges? +

Shipping cost does not include the majority of customs fees and charges.

Failure to pay customs fees required to complete delivery may result in your package being abandoned by the courier. No refund will be issued for abandoned items.

Packages that are refused delivery or are returned for other reasons will incur return fees and may no longer qualify for a full refund.

Can I still change my address after my order is shipped out? +

No, you cannot, but you can ask the courier to intercept your package. The courier will hold your package awaiting further instructions. Please call the courier service for more details.

What if I didn't receive my order and the status says returned to sender? +

A problem in your address or that the package cannot be delivered could be the reason for why it was returned. To reship your order, we need the payment of a return fee + new shipping fees whenever applicable.

Return fees are fees charged by UPS for orders returned to us and vary depending on the size and weight of the order.

If my order/shipment states return to sender, can I get a refund instead? +

We can refund upon payment of the return fee. The fee can be deducted from the total amount available for refund.

If my order arrived damaged or broken, what should I do? +

Contact us soon as possible for assistance and provide all necessary files and documents:

  • Receipt or invoice
  • Photos of your package and contents
  • Shipping label posted on the box
  • The documents included in the shipment if any
  • Photos of the Items broken
  • Any other relevant information

We can reship you the broken or damaged order or you can also file a claim with the courier service if your order arrived damaged to recover the value of the broken order. We are happy to assist you in all courier claims as best as we can.

If my package is missing an item what should I do? +

Contact us soon as possible for assistance and provide all necessary files and documents.

  • Receipt or invoice
  • Detailed photos of your package. Include photos of your package in its current condition.
  • Shipping label
  • Documents included in the shipment clearly that clearly identify the contents and what is expected

We can ship you the missing items or you can also file a claim with the courier service if your order arrived damaged. We are happy to assist you in all courier claims as best as we can.

When will my order be shipped? +

Orders take 1-2 business days to process and are shipped promptly. We do not ship orders during the weekend or during US holidays.

Orders are confirmed when they get a tracking number.

How do I track my order? +

Orders take 1-2 business days to process and are shipped promptly. We do not ship orders during the weekend or during US holidays.

Orders are confirmed when they get a tracking number.

How do I track my order? +

Use our chat box to track your order or get updates directly from your email. Order updates are sent to your registered email and will have a tracking link available.

Where can I find my order number? +

You can find your order number in the order notification sent to you via email.

How much do you charge for shipping? +

All orders shipped to the USA are shipped free.

For overseas orders, order weight and location determine the shipping rates in real time.

You can check for shipping rates by adding the product you like to the cart, then proceed to checkout.

In the checkout, add in your address and allow the page to get real time shipping rates.

UPS, DHL and USPS handle domestic USA shipping and UPS, DHL and USPS for international shipping.

Customs fees and charges are not included in the shipping offer.

At this time, due to custom regulations we are unable to ship to Mexico

Do you cover customs fees and charges? +

Shipping cost does not include the majority of customs fees and charges.

Failure to pay customs fees required to complete delivery may result in your package being abandoned by the courier. No refund will be issued for abandoned items.

Packages that are refused delivery or are returned for other reasons will incur return fees and may no longer qualify for a full refund.

Can I still change my address after my order is shipped out? +

No, you cannot, but you can ask the courier to intercept your package. The courier will hold your package awaiting further instructions. Please call the courier service for more details.

What if I didn't receive my order and the status says returned to sender? +

A problem in your address or that the package cannot be delivered could be the reason for why it was returned. To reship your order, we need the payment of a return fee + new shipping fees whenever applicable.

Return fees are fees charged by UPS for orders returned to us and vary depending on the size and weight of the order.

If my order/shipment states return to sender, can I get a refund instead? +

We can refund upon payment of the return fee. The fee can be deducted from the total amount available for refund.

If my order arrived damaged or broken, what should I do? +

Contact us soon as possible for assistance and provide all necessary files and documents:

  • Receipt or invoice
  • Photos of your package and contents
  • Shipping label posted on the box
  • The documents included in the shipment if any
  • Photos of the Items broken
  • Any other relevant information

We can reship you the broken or damaged order or you can also file a claim with the courier service if your order arrived damaged to recover the value of the broken order. We are happy to assist you in all courier claims as best as we can.

If my package is missing an item what should I do? +

Contact us soon as possible for assistance and provide all necessary files and documents.

  • Receipt or invoice
  • Detailed photos of your package. Include photos of your package in its current condition.
  • Shipping label
  • Documents included in the shipment clearly that clearly identify the contents and what is expected

We can ship you the missing items or you can also file a claim with the courier service if your order arrived damaged. We are happy to assist you in all courier claims as best as we can.

What are subscriptions? +

Subscriptions are recurring discounted monthly orders. They allow you to automate delivery and maintain your supply for a discounted cost and are the perfect option if you need a guaranteed supply of your product.

How do I manage my subscription? +

A link is provided in the subscription confirmation email allowing you access to your customer portal. You can update your address, skip or change order dates, add, remove or swap products in the subscription, and many more.

If I want to cancel a subscription order what do I do? +

You can cancel your subscription at any time before the order is dispatched and the tracking number assigned.

You will be notified five days in advance of a scheduled order being dispatched.

Access your customer subscription portal and modify or change your next order date accordingly. If you need assistance, please contact us.

How do I change my payment information? +

Log-in to your customer portal and change your payment details. If you need assistance, please contact us.

How do I skip the next order? +

Access your customer portal to make edits to your subscription.

Can I change my order frequency? +

Yes, you can change your order frequency between 30 days and 60 days. If you'd like to make this change, please contact us at purblack.com/contact-us

Can I change the items in my order? +

Yes you make adjustments to the products in your subscriptions for eligible products.

What is your return policy? +

Returns are allowed within 30 days of delivery. Some conditions apply.

Initiate the return process by submitting a request through our Contact Us page.

For hygiene reasons, your item must meet certain criteria to qualify for a return. It should be in its original condition, unopened, unused, and in the original packaging.

Additionally, a valid receipt or proof of purchase.

What is your refund policy? +

Upon receiving and inspecting your return, we will notify you of the approval. If approved, a refund will be automatically processed to your original payment method. Keep in mind that it may take some time for your bank or credit card company to complete the refund transaction.

Any returns fee due an order will be deducted from the final refund amount.

Stories of other athletes:

References:
1. Fatigue Resistance & Exercise Performance

Keller, J. L., et al. (2019). The effects of shilajit supplementation on fatigue-induced decreases in muscular strength and serum hydroxyproline levels. Journal of the International Society of Sports Nutrition, 16:3.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6364418/

2. Collagen Synthesis & Musculoskeletal Adaptation

Neltner, T. J., et al. (2023). Effects of 8 weeks of shilajit supplementation on serum Pro-C1α1: A biomarker of type I collagen synthesis: A randomized control trial. Journal of Dietary Supplements.

https://pubmed.ncbi.nlm.nih.gov/36535768/

3. Mitochondrial Function & Cellular Energy Support

Carrasco-Gallardo, C., Guzmán, L., & Maccioni, R. B. (2012). Shilajit: a natural phytocomplex with potential procognitive activity. International Journal of Alzheimer’s Disease, 2012:6741428.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3296184/