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Core Labs Mass + Rx

Core Labs 60 Caps

from £36.40

Earn up to 47 Points.

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Orders placed before 4 pm are shipped on the same day

Free shipping: UK over £89, EU over £150
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Core Labs Mass RX is a capsule-based supplement that delivers a proprietary compound combined with a botanical support blend. It’s designed for structured, time-limited use by experienced adult users following planned supplementation routines. Each serving supports consistency across a defined usage period.

Packaging

  • 60 capsules per bottle, suitable for up to 60 days of use when taken consistently as directed

Key Components (per capsule)


  • Core compound – approx. 25 mgCarefully measured ingredients are included in advanced supplement protocols.


  • Botanical support microblend – approx. 15 mgA plant-derived formulation intended to help maintain product consistency and stability.


Additional ingredients may include microcrystalline cellulose, capsule shell material (e.g. gelatin or vegetarian alternative), magnesium stearate, silicon dioxide, and phytosterols—used to maintain shelf stability and consistent dosage delivery.
Suggested Use


  • Take 1 capsule daily, preferably with a meal.


  • Do not exceed 1 capsule within any 24‑hour period.


  • Recommended usage cycle: 4 to 6 weeks, followed by a planned break or transition based on your supplementation schedule.


Intended User
This product is intended for healthy adult males aged 21 and over with familiarity in structured, cycle-based supplementation routines. It is not suitable for women, minors, or individuals with underlying medical conditions. Consultation with a qualified healthcare professional is advised before beginning use.
Storage & Safety Information


  • Store in a cool, dry place, away from direct light and moisture.


  • Keep out of reach of children.


  • Use only as directed.


  • Do not exceed the recommended daily serving.


DOSAGE-TIMING-FOLLOW-UP:


Mass + Rx from Core Labs, which includes high-impact anabolic ingredients, requires a disciplined approach to supplementation. This includes a proper on-cycle regimen, post-cycle therapy (PCT), and supportive measures to protect the body’s vital systems, particularly the liver. Here’s a recommended approach:

Supplementation Cycle for Mass + Rx:


On-Cycle Phase:
Duration:Considering the potency, a cycle should be limited to 4-6 weeks.
Dosage:The manufacturer suggests two capsules daily, split into two doses one in the morning and one in the evening.
Supportive Measures:Given the inclusion of NAC (N-acetylcysteine), additional liver support may not be necessary, but it’s wise to consider comprehensive on-cycle support, including cardiovascular and hormonal health.
Off-Cycle Phase:
Duration:An off-cycle of at least 6-8 weeks is advised to allow the body to recover and reset its natural hormonal balance.
Abstinence:Cease all anabolic supplements during this period.
Post-Cycle Therapy (PCT):
Testosterone Support:Supplements that encourage the body’s natural testosterone production, like D-aspartic acid, herbal extracts, or zinc, should be used.
Estrogen Regulation:If necessary, incorporate an over-the-counter aromatase inhibitor to manage potential increases in estrogen.
Cortisol Management:Consider adding cortisol blockers to maintain the gains achieved during the cycle.
Protective Measures:
Antioxidants:Additional antioxidants like Vitamin C may help mitigate oxidative stress.
Cardiovascular Health:Continue Vitamin E supplementation and consider Omega-3 fatty acids and CoQ10.
Joint Care:Supplements like Glucosamine and Chondroitin can be beneficial, mainly if the cycle includes heavy lifting.
Monitoring and Adjustments:
Regular Health Checks:Blood tests to monitor liver enzymes, lipid profiles, and hormonal panels before, during, and after the cycle are recommended.
Adaptation:Adjust the dose, stop the cycle if adverse reactions occur, and seek medical advice.
This product is a dietary supplement and should not be used as a substitute for a varied diet. Do not exceed the recommended daily dose. Keep out of reach of children. If you are pregnant, nursing, taking medication, or have a medical condition, consult your healthcare professional before use. This product contains Aphrodyne and may cause side effects such as increased heart rate, anxiety, or elevated blood pressure. Use with caution and discontinue use if any adverse reactions occur. Store in a cool, dry place away from direct sunlight. The Food and Drug Administration or any other governmental authority has not evaluated the statements made here. This product is not intended to diagnose, treat, cure, or prevent any disease.

No product reviews yet — add the first one!

Need help?

We offer a variety of sports supplements, including muscle-building products, pre-workout formulas, post-exercise recovery items, vitamins and minerals, amino acids, and more.

All our supplements are sourced from reputable manufacturers and undergo rigorous quality control to ensure safety and efficacy. However, we recommend consulting a healthcare professional before starting any new supplement regimen.

Choosing the right supplement depends on your fitness goals, dietary needs, and any existing health conditions. Our product descriptions provide detailed information to help you make an informed decision. Contact our customer support team for personalised advice if you need more clarification.

Placing an order is simple. Please browse our products, add the items you’d like to your cart, and proceed to checkout. You can pay using credit or debit cards, Klarna, or LayBuy.

We offer both domestic and international shipping. Orders are typically processed within 1-2 business days; however, shipping times may vary by location. For detailed information, please refer to our Shipping Policy page.

Once your order is shipped, you will receive a confirmation email with a tracking number. You can use this number to track your order on the carrier’s website.

We offer a carrier ‘s-day return policy for unopened and unused products. If you are unsatisfied with your purchase, please contact our customer support team to initiate a return. For more details, please visit our Return Policy page.

Yes, we regularly offer discounts and promotions on various products. Sign up for our newsletter or follow us on social media to stay updated on the latest deals.

Absolutely! Our team of experts is here to help. Contact us via our website, and we will provide personalised recommendations tailored to your fitness goals and dietary needs.

We offer a selection of vegan—and vegetarian-friendly supplements. For specific information, please check the product descriptions or use the filter options on our website to find suitable products.

Please email our customer support team at info@crossthelimits.co.uk or speak directly to our AI bot assistant. We aim to respond to all inquiries within 24 hours.

We offer wholesale options for gyms, fitness centres, and retailers. For more information, please contact our wholesale department at wholesale@crossthelimits.co.uk.

Your order still needs to be completed” Our payment”gateway most likely did not accept your card. In such cases, the bank often holds the funds as “pending, ” which should be returned to your account within three business days.

If your card was not accepted when placing an order, please try using a different card or select an alternative payment gateway from the list on the payment page after placing your order.

We dispatch parcels to the EU every Friday. Your order must be placed by 10 AM on Friday to be included in that week’s shipment. If you order earlier in the week (e.g. on Sunday), your parcel will stay in the UK until Thursday, when it is transferred to our EU fulfilment centre. Once it arrives (usually within 5-7 days), we will send it via DPD, and you will receive your tracking details via email. Please note that the journey from the UK to the EU warehouse does not include tracking—tracking is only provided once your parcel is dispatched from the EU warehouse.

First, you’ll need to register for an account with our store to earn your points. Our points system lets you earn points on every purchase. For every £1 spent on our website, you earn 1 point. For every 100 points, you get £1 in store credit.

For example, if you order £100, you will earn 100 points (equivalent to £1), which you can redeem on your next order.

Yes! You can pay for your supplements using Bitcoin (BTC), Ethereum (ETH), USDT, and many other cryptocurrencies via our secure payment partner, NOWPayments.

To ensure reliable delivery and avoid customs issues, all UK orders are shipped via a consolidated weekly route to our EU hub.

This method guarantees:

  • No customs delays
  • No VAT or duty on delivery
  • One fixed shipping fee (£15)

Orders placed after Friday may be included in the following dispatch window.

Delivery time can be up to 2–2.5 weeks, depending on order timing.

All parcels are delivered via DPD with EU tracking provided after dispatch.

Core Labs

Core Labs

Cross the Limits offers Core Labs supplements, a trusted name in the fitness world known for innovative dietary supplements and advanced training-oriented nutrition. This range delivers high-performance products tailored for athletes at every level, focusing on efficiency and effective goal achievement. By choosing Core Labs at Cross the Limits, fitness enthusiasts gain access to professional-grade formulations designed to maximize physical potential.

Core Labs Mass + Rx 60 Caps

This product is currently out of stock and unavailable.

Out of stock

Orders placed before 4 pm are shipped on the same day

Free shipping: UK over £89, EU over £150
Secure Card Payments
visa master gpay apay
Pay later with Klarna - interest free
14-Day Returns

Core Labs X MASS – Advanced Capsule Supplement


Core Labs X MASS is a capsule-based dietary supplement created for experienced users who prefer clearly defined products that fit into a structured training and nutrition routine. Designed with simplicity in mind, this formula focuses on precision dosing, convenience, and ease of integration into advanced supplementation stacks.


The capsule format allows for controlled daily intake, making it suitable for users who value consistency and flexibility alongside demanding training schedules.







Product Characteristics




  • Capsule form for convenient use




  • Simple, no-nonsense presentation




  • Designed for experienced supplement users




  • Easy to stack with pre-workouts, pump formulas, or daily basics




  • Compact format – ideal for travel or everyday use




Core Labs X MASS is aimed at athletes who understand that supplementation is only one element of a disciplined lifestyle, alongside training, nutrition, and recovery habits.







Who Is This Product For?




  • Experienced adult users




  • Individuals following structured training programs




  • Athletes who prefer capsule-based supplements




  • Users who value simplicity and controlled supplementation








Suggested Use


Follow the manufacturer’s recommended dosage as stated on the product label.
Do not exceed the recommended daily intake.







Important Information




  • Food supplement




  • Intended for healthy adults only




  • Not suitable for children




  • Not recommended during pregnancy or breastfeeding




  • Not intended as a substitute for a varied diet and healthy lifestyle




  • Store in a cool, dry place away from direct sunlight




If you are taking medication or have health concerns, consult a qualified professional before use.







Disclaimer: This product is a dietary supplement and should not be used as a substitute for a varied diet. Do not exceed the recommended daily dose. Keep out of reach of children. If you are pregnant, nursing, taking medication, or have a medical condition, consult your healthcare professional before use. This product contains Aphrodyne and may cause side effects such as increased heart rate, anxiety, or elevated blood pressure. Use with caution and discontinue use if any adverse reactions occur. Store in a cool, dry place away from direct sunlight. The Food and Drug Administration or any other governmental authority has not evaluated the statements made here. This product is not intended to diagnose, treat, cure, or prevent any disease.

No product reviews yet — add the first one!

Need help?

We offer a variety of sports supplements, including muscle-building products, pre-workout formulas, post-exercise recovery items, vitamins and minerals, amino acids, and more.

All our supplements are sourced from reputable manufacturers and undergo rigorous quality control to ensure safety and efficacy. However, we recommend consulting a healthcare professional before starting any new supplement regimen.

Choosing the right supplement depends on your fitness goals, dietary needs, and any existing health conditions. Our product descriptions provide detailed information to help you make an informed decision. Contact our customer support team for personalised advice if you need more clarification.

Placing an order is simple. Please browse our products, add the items you’d like to your cart, and proceed to checkout. You can pay using credit or debit cards, Klarna, or LayBuy.

We offer both domestic and international shipping. Orders are typically processed within 1-2 business days; however, shipping times may vary by location. For detailed information, please refer to our Shipping Policy page.

Once your order is shipped, you will receive a confirmation email with a tracking number. You can use this number to track your order on the carrier’s website.

We offer a carrier ‘s-day return policy for unopened and unused products. If you are unsatisfied with your purchase, please contact our customer support team to initiate a return. For more details, please visit our Return Policy page.

Yes, we regularly offer discounts and promotions on various products. Sign up for our newsletter or follow us on social media to stay updated on the latest deals.

Absolutely! Our team of experts is here to help. Contact us via our website, and we will provide personalised recommendations tailored to your fitness goals and dietary needs.

We offer a selection of vegan—and vegetarian-friendly supplements. For specific information, please check the product descriptions or use the filter options on our website to find suitable products.

Please email our customer support team at info@crossthelimits.co.uk or speak directly to our AI bot assistant. We aim to respond to all inquiries within 24 hours.

We offer wholesale options for gyms, fitness centres, and retailers. For more information, please contact our wholesale department at wholesale@crossthelimits.co.uk.

Your order still needs to be completed” Our payment”gateway most likely did not accept your card. In such cases, the bank often holds the funds as “pending, ” which should be returned to your account within three business days.

If your card was not accepted when placing an order, please try using a different card or select an alternative payment gateway from the list on the payment page after placing your order.

We dispatch parcels to the EU every Friday. Your order must be placed by 10 AM on Friday to be included in that week’s shipment. If you order earlier in the week (e.g. on Sunday), your parcel will stay in the UK until Thursday, when it is transferred to our EU fulfilment centre. Once it arrives (usually within 5-7 days), we will send it via DPD, and you will receive your tracking details via email. Please note that the journey from the UK to the EU warehouse does not include tracking—tracking is only provided once your parcel is dispatched from the EU warehouse.

First, you’ll need to register for an account with our store to earn your points. Our points system lets you earn points on every purchase. For every £1 spent on our website, you earn 1 point. For every 100 points, you get £1 in store credit.

For example, if you order £100, you will earn 100 points (equivalent to £1), which you can redeem on your next order.

Yes! You can pay for your supplements using Bitcoin (BTC), Ethereum (ETH), USDT, and many other cryptocurrencies via our secure payment partner, NOWPayments.

To ensure reliable delivery and avoid customs issues, all UK orders are shipped via a consolidated weekly route to our EU hub.

This method guarantees:

  • No customs delays
  • No VAT or duty on delivery
  • One fixed shipping fee (£15)

Orders placed after Friday may be included in the following dispatch window.

Delivery time can be up to 2–2.5 weeks, depending on order timing.

All parcels are delivered via DPD with EU tracking provided after dispatch.

Core Labs

Core Labs

Cross the Limits offers Core Labs supplements, a trusted name in the fitness world known for innovative dietary supplements and advanced training-oriented nutrition. This range delivers high-performance products tailored for athletes at every level, focusing on efficiency and effective goal achievement. By choosing Core Labs at Cross the Limits, fitness enthusiasts gain access to professional-grade formulations designed to maximize physical potential.