ON SERIOUS MASS – 6lb

Nutritional Information — Optimum Nutrition Serious Mass 6LB

Serving size: 2 heaping scoops (approximately 334g). Servings per container: 8 (6LB / 2,727g).

Note: Values shown in water are based on the confirmed supplement facts panel from the official Optimum Nutrition product page, Vitacost, AmeriLife, and GNC authorised listings. Values with low-fat milk are from the official ON product page. Client to verify final values against the specific physical 6LB product label for the Sports One-stocked batch before publishing, as minor formulation updates may occur between production runs.

Ingredients

Maltodextrin, Protein Blend (Whey Protein Concentrate, Calcium Caseinate, Egg Albumen, Sweet Dairy Whey), Cocoa Processed with Alkali (Chocolate variant), Natural and Artificial Flavors, Vitamin and Mineral Blend (Di-Potassium Phosphate, Magnesium Aspartate, Di-Calcium Phosphate, Calcium Citrate, Ascorbic Acid, Niacinamide, Zinc Citrate, Beta Carotene, D-Calcium Pantothenate, D-Alpha Tocopheryl Succinate, Selenomethionine, Copper Gluconate, Ferrous Fumarate, Manganese Amino Acid Chelate, Thiamin Mononitrate, Pyridoxine Hydrochloride, Riboflavin, Chromium Polynicotinate, Folic Acid, Biotin, Molybdenum Amino Acid Chelate, Cholecalciferol, Potassium Iodide, Cyanocobalamin), L-Glutamine, Creatine Monohydrate, Acesulfame Potassium, Lecithin, Medium Chain Triglycerides.

Note: Ingredients shown reflect the Chocolate variant. Other flavour variants omit Cocoa and use different colour and flavour systems. Contains milk, egg, wheat (glutamine peptides), and soy (lecithin) ingredients.

Key Ingredient Roles

Allergen Warning: Contains milk, egg, wheat (glutamine peptides), and soy (lecithin) ingredients. Not suitable for individuals with allergies to any of these ingredients. Consult a physician before use if you are taking medication or under a physician’s care for a medical condition. Keep out of reach of children. Only intended for adults 18 years of age or older. Not for use by pregnant or nursing women.

Key Benefits of Optimum Nutrition Serious Mass 6LB

Serious Mass earns its place at the top of the mass gainer category not through marketing but through what it delivers per serving. The benefits below break down exactly what each component contributes and why it matters for athletes who are genuinely serious about gaining size.

1,250 Calories Per Serving — the Highest Calorie-Per-Serving Mass Gainer Available

At 1,250 calories per serving in water and over 1,630 calories when mixed with low-fat milk, Serious Mass provides more caloric impact per serving than any comparable mass gainer widely available in Pakistan. To put this in context, a single Serious Mass serving in milk is roughly equivalent to three to four whole food meals in caloric contribution. For hardgainers who need to consume 3,500 to 4,500 calories per day to create a meaningful surplus but struggle to eat enough volume, one to two Serious Mass servings can bridge the gap between what whole food provides and what the body actually needs to grow.

50g of Blended Protein from Four Distinct Sources

The protein blend in Serious Mass uses Whey Protein Concentrate for fast early-phase amino acid delivery, Calcium Caseinate for a slower sustained release that extends the anabolic window for hours, Egg Albumen for a complete, high-bioavailability amino acid profile from a non-dairy source, and Sweet Dairy Whey for additional whey-fraction amino acid coverage. This four-source approach produces a broader and more sustained amino acid elevation than a single-source whey concentrate alone, making each serving effective across both the immediate post-workout recovery window and the extended period between meals.

8g of Naturally Occurring Glutamine Per Serving

Each serving of Serious Mass delivers 8g of naturally occurring glutamine. Glutamine is the most abundant amino acid in skeletal muscle and plays a documented role in post-exercise recovery, nitrogen retention, immune function maintenance, and gut health under the heavy metabolic demands of high-volume, high-calorie training. The 8g per serving, rising to 10g when mixed with milk, is a meaningful and functional dose that supports recovery between the frequent heavy training sessions that a serious bulk phase requires.

5g of Creatine Monohydrate — a Full Clinical Daily Dose Built In

The 5g of creatine monohydrate per Serious Mass serving is not a trace inclusion for label purposes. This is a full clinical daily maintenance dose, consistent with the 3-5g per day range recommended in the ISSN position stand on creatine supplementation. For athletes using Serious Mass daily, this eliminates the need for a separate creatine product entirely, reducing both supplement spend and the complexity of managing multiple daily additions to a shake.

Over 250g of Carbohydrates with No Added Sugar

The carbohydrate matrix in Serious Mass delivers over 254g of carbohydrates per serving from maltodextrin as the primary source, with the 21g of sugar per serving being naturally occurring rather than added. This is nutritionally significant because the caloric load is driven by complex carbohydrate energy that replenishes muscle glycogen and supports training intensity, rather than from added sugar that drives disproportionate fat storage and reduces the quality of the caloric surplus. For hardgainers needing to consume carbohydrates in large quantities, the no-added-sugar label means those carbohydrates are doing productive work rather than working against body composition goals.

25 Vitamins and Essential Minerals Per Serving

Serious Mass includes a comprehensive 25-vitamin and mineral blend with a deliberate emphasis on B-vitamins and antioxidants. The B-vitamin emphasis addresses the fact that intensive bulking training dramatically increases the demand for energy metabolism co-factors such as B1, B2, B3, B6, and B12. The antioxidant emphasis (Vitamins C, E, A as beta carotene, Selenium) supports the oxidative stress management that high-frequency, high-volume training creates. Key minerals including 15mg Zinc, 140mg Magnesium, 630mg Calcium, and 120mcg Chromium contribute to hormonal health, bone maintenance, and glucose metabolism respectively, all of which are relevant to the physiological demands of a sustained bulk.

MCTs for Clean Calorie Contribution Without Fat Storage Risk

Serious Mass includes Medium Chain Triglycerides (MCTs) as its primary fat source. Unlike long-chain dietary fats that are packaged into chylomicrons and transported through the lymphatic system before reaching circulation, MCTs are absorbed directly into the portal vein and metabolised rapidly in the liver for energy. This means the fat calories in Serious Mass are processed for energy rather than directed toward fat storage, contributing to the caloric surplus productively rather than adding to body fat accumulation alongside muscle.

Instantized Formula — Mixes Without a Blender When Needed

While ON recommends blending Serious Mass for the smoothest result given its 334g serving size, the formula is instantized to allow mixing without a blender when required. Athletes travelling, at work, or without blender access can prepare a Serious Mass shake with a shaker cup and cold water, maintaining their caloric and protein protocol without being limited to gym or home use. The flavours are designed to taste genuinely good even when mixed with water rather than milk, which is practically important for athletes who use water to keep calories controlled.

How to Use Optimum Nutrition Serious Mass

Serious Mass is a substantial weight-gain supplement that works best when used consistently at the right times and in the right quantities for your specific goals and body size. New users should begin at a reduced dose to allow digestive adaptation before moving to a full serving.

Preparation Instructions

Add two heaping scoops (approximately 334g) of Serious Mass to a blender filled with 24 oz (710ml) of cold water. Blend for 45-60 seconds. Then add a few ice cubes and, if desired, other calorie-contributing ingredients such as peanut butter, oats, banana, or whole milk, and blend for an additional 30-45 seconds. Mixing with low-fat milk instead of water increases the serving to over 1,630 calories with 66g of protein and produces a thicker, creamier shake. New users should start with half a serving (one scoop) daily for the first week to assess digestive tolerance before progressing to a full two-scoop serving.

Supercharge Your Serious Mass (Blender Additions)

• For maximum bulk: Add full-fat milk, two tablespoons of peanut butter, half a cup of oats, and a banana to your two-scoop base. This can push a single serving to 2,000 calories or more with additional fibre, healthy fats, and micronutrients from whole food sources.
• For lean bulk: Use cold water and add a tablespoon of almond butter for healthy fat without excessive saturated fat contribution. This keeps the serving closer to 1,300-1,400 calories while adding nutritional density.
• For faster blending: Add liquid first, then powder, before blending to prevent clumping at the base of the blender.

Timing Tips

• Post-workout (primary window): Begin consuming half to one full serving 30-45 minutes after exercise to maximise nutrient utilisation when muscles are most receptive to protein and carbohydrate replenishment. The combined creatine and protein delivery during this window is one of the most well-supported timing protocols in sports nutrition research. See why post-workout nutrition timing drives measurably better bulking results.
• Before bed: Drink half to one serving 45-60 minutes before sleep to provide protein and calories to regenerate muscles throughout the overnight recovery period. The calcium caseinate fraction specifically supports overnight amino acid availability due to its slower digestion rate.
• Between meals: Use half to one serving between main meals to maintain a consistent caloric surplus across the full day rather than relying on large meals that are difficult for hardgainers to manage.
• On non-training days: Continue one serving daily on rest days to maintain the caloric surplus and protein intake that muscle growth requires continuously, not just on days with a training stimulus.

Dosage by Goal and Bodyweight

• Beginners and athletes under 70KG: Start with one scoop (half serving) daily for the first week, then progress to one full two-scoop serving once or twice daily depending on total daily caloric targets.
• Intermediate athletes 70-90KG in a mass phase: One full serving daily post-workout plus one half-serving before bed is an effective starting protocol covering approximately 1,875 calories from Serious Mass alone.
• Advanced athletes over 90KG or those needing very high caloric intake: Two full servings daily (post-workout and before bed) provides 2,500 calories from Serious Mass, leaving the balance of daily caloric needs to whole food sources.

Recommended Stack

Since Serious Mass includes 5g of creatine monohydrate per serving, a separate standalone creatine product is not needed during daily Serious Mass use. A pre-workout supplement on training days covers energy and focus for the session. A BCAA product intra-workout adds amino acid coverage during extended training sessions. A daily multivitamin can supplement the 25 vitamins and minerals already in Serious Mass on particularly demanding training days.

Storage Instructions

Store in a cool, dry place away from direct heat and sunlight. Keep the container tightly sealed after every use to prevent moisture absorption, which can cause the maltodextrin to clump. Do not refrigerate the powder. Ideal storage temperature is between 15 and 25 degrees Celsius. For general guidance on how long an opened mass gainer container stays effective, see how to manage supplement shelf life after opening.

Warnings

Intended for adults 18 years of age or older only. Not for use by pregnant or nursing women. Consult a physician before use if you are taking medication or under a physician’s care for a medical condition. Contains milk, egg, wheat (glutamine peptides), and soy (lecithin) ingredients. Not suitable for individuals with allergies to any of these ingredients. Do not use as a sole source of nutrition. Keep out of reach of children.

Why Buy Optimum Nutrition Serious Mass from Sports One

Sports One International is Pakistan’s authorised distributor of Halal-certified supplements since 2002. Every unit of Optimum Nutrition Serious Mass 6LB sold through Sports One is 100% genuine, properly imported, and backed by official distributor agreements. Serious Mass is one of the most searched and most counterfeited products in the Pakistani supplement market. Knowing how to verify that a supplement is original before purchasing, and understanding why a price that is too low signals a serious product risk, is especially important for a product at this caloric and serving size. Find us in Lahore, Karachi, Islamabad, and Gujranwala or order online with fast nationwide delivery.

The Science Behind Optimum Nutrition Serious Mass

Every component of Serious Mass is grounded in published research. The sections below cover the evidence base for caloric surplus and muscle gain, the four-source protein blend, creatine monohydrate, glutamine, MCTs, and the micronutrient panel, explaining why each element is present at its specific dose.

Caloric Surplus and Muscle Mass Accumulation

Muscle growth requires a caloric surplus over time. Research published in the American Journal of Clinical Nutrition (PubMed PMID 19198647) confirmed that athletes in a caloric surplus combined with resistance training gained significantly more lean mass than those in energy balance with identical training, establishing the fundamental mechanism that Serious Mass is specifically designed to support. For hardgainers whose total daily caloric intake falls below their expenditure despite eating substantial whole-food meals, a product delivering 1,250 to 1,630 calories per serving directly addresses the rate-limiting factor in their muscle development.

Multi-Source Protein Blend and Sustained Amino Acid Delivery

The four-source protein blend in Serious Mass (WPC, calcium caseinate, egg albumen, sweet dairy whey) provides both fast and slow amino acid delivery. A landmark study published in the Journal of Nutrition (PubMed PMID 23343671) found that a blend of whey, casein, and soy protein produced a significantly more sustained muscle protein synthesis response over five hours compared to whey protein alone, directly supporting the multi-source approach used in Serious Mass.

Creatine Monohydrate: Clinical Evidence for the 5g Dose

The 5g of creatine monohydrate per Serious Mass serving is consistent with the ISSN-recommended daily maintenance dose. The ISSN Position Stand on creatine supplementation, published in the Journal of the International Society of Sports Nutrition, confirms creatine monohydrate as the most effective ergogenic nutritional supplement currently available for increasing high-intensity exercise capacity and lean body mass, with no clinically relevant safety concerns at the recommended dose in healthy adults.

Glutamine and Post-Exercise Recovery

The 8g of naturally occurring glutamine per Serious Mass serving addresses the well-documented post-exercise decline in plasma glutamine that follows intense resistance training. Research reviewed at the NIH National Library of Medicine (PMC4369670) confirmed that glutamine supplementation post-exercise reduced muscle damage markers, accelerated glycogen replenishment, and supported immune function in athletes under heavy training loads, all of which are directly relevant to the recovery demands of a serious bulking protocol.

MCTs and Metabolic Caloric Quality

The Medium Chain Triglycerides in Serious Mass provide a fat source with meaningfully different metabolic handling than standard long-chain dietary fats. Research published in the NIH National Library of Medicine (PMC4882694) confirmed that MCT consumption is associated with increased energy expenditure and a more favourable body composition profile compared to equivalent doses of long-chain fatty acids, supporting the use of MCTs in a bulking formula where the quality and metabolic fate of calorie sources matters alongside their total quantity.

B-Vitamins, Energy Metabolism, and Bulking Phase Demands

The 25-vitamin and mineral blend in Serious Mass emphasises B-vitamins, with niacin at 250% DV, Vitamin B6 at 250% DV, and Vitamin B12 at 167% DV per serving. B-vitamins function as co-factors in the metabolic pathways that convert the protein and carbohydrate substrate of a high-calorie diet into usable cellular energy. Research from the NIH National Library of Medicine (PMC4772032) confirms that athletes engaged in high-intensity training have significantly elevated B-vitamin requirements compared to sedentary individuals, making the above-daily-value B-vitamin inclusion in Serious Mass genuinely relevant rather than a generic vitamin addition.

Carbohydrate Quality and Glycogen Resynthesis

The 254g of carbohydrates per Serious Mass serving, delivered primarily through maltodextrin, supports rapid post-exercise glycogen resynthesis. Research published in the Journal of the International Society of Sports Nutrition confirms that consuming carbohydrates alongside protein post-exercise enhances glycogen resynthesis and does not reduce the muscle protein synthesis response, supporting the co-delivery of carbohydrates and protein within a single Serious Mass serving as a sound nutritional strategy rather than a caloric shortcut.

Frequently Asked Questions — Optimum Nutrition Serious Mass 6LB

What is Optimum Nutrition Serious Mass used for?

Serious Mass is Optimum Nutrition’s highest-calorie weight gain formula, designed specifically for hardgainers and athletes who need a substantial caloric surplus to build muscle mass but struggle to achieve that surplus through whole food alone. Each two-scoop serving delivers 1,250 calories in water, 50g of four-source blended protein, over 254g of carbohydrates with no added sugar, 5g of creatine monohydrate, 8g of naturally occurring glutamine, and 25 essential vitamins and minerals, consolidating what would otherwise require multiple separate supplements and additional meals into a single shake.

What is the Serious Mass price in Pakistan?

For the current Optimum Nutrition Serious Mass 6LB price in Pakistan, visit the Sports One product page directly. Sports One is the authorised importer, meaning you are paying for the genuine product with full label accuracy and authenticity guarantees. For a full comparison of mass gainer prices in Pakistan, see the Sports One Serious Mass price and review guide.

Is Optimum Nutrition Serious Mass Halal?

Optimum Nutrition Serious Mass is sold through Sports One International, Pakistan’s authorised distributor of Halal-certified supplements since 2002. For specific Halal certification documentation for Serious Mass, contact Sports One directly or visit the certification page.

How many servings are in the 6LB tub?

The 6LB (2,727g) container provides 8 full two-scoop servings at the standard 334g serving size. At one full serving per day, the tub lasts 8 days. Most athletes use Serious Mass as a post-workout and before-bed supplement rather than as a sole daily intake driver, so it typically fits within a longer-term rotation depending on frequency. For consistent long-term use, the 12LB format provides significantly better cost-per-serving value.

Do I need to take creatine separately with Serious Mass?

No. Serious Mass already includes 5g of creatine monohydrate per serving, which is a full clinical daily maintenance dose within the 3-5g per day range recommended by the ISSN. Athletes using Serious Mass daily do not need to purchase or manage a separate creatine supplement, which simplifies the stack and reduces overall supplement spend.

Can beginners use Serious Mass?

Yes, though beginners should start with half a serving (one scoop) daily for the first week to allow the digestive system to adapt to the large serving volume and the creatine content before progressing to a full two-scoop serving. Beginners should also treat Serious Mass as an addition to an existing whole-food diet rather than a replacement for it, and should pair it with a structured resistance training programme to direct the caloric surplus toward muscle rather than fat accumulation.

How do I make Serious Mass taste better?

The simplest improvement is to use cold low-fat or full-fat milk instead of water, which significantly improves texture, creaminess, and flavour richness while adding protein and calories. Blending with ice cubes produces a noticeably smoother result than shaking. Adding a banana, tablespoon of peanut butter, or half a cup of oats creates a genuinely substantial, dessert-quality mass shake while adding nutritional value beyond what the powder alone provides.

Is Serious Mass suitable for use before bed?

Yes, and ON specifically recommends consuming half to one serving 45-60 minutes before sleep to provide nutrients for overnight muscle regeneration. The calcium caseinate fraction in the protein blend is a slow-digesting protein that provides a sustained amino acid release through the overnight period, making Serious Mass a practical pre-sleep option particularly for athletes who find it difficult to consume a large casein-specific meal before bed.