Optimum Serious Mass 6lbs

$89.95 $69.97 Save $19.98

Shipping calculated at checkout.

Quantity

Optimum Nutrition Serious Mass – High-Calorie Mass Gainer for Size Goals (6lbs)

Optimum Nutrition Serious Mass by Optimum Nutrition is a high-calorie mass gainer designed to support weight gain, size goals, and increased daily calorie intake for hard-gainers and active individuals with high energy demands.

With a blend of calories, protein, carbohydrates, and added nutrients, Serious Mass provides a convenient way to support muscle-building nutrition when meeting calorie needs through food alone is challenging.

What Is Optimum Nutrition Serious Mass?

Optimum Nutrition Serious Mass is formulated to:

Support increased daily calorie intake
Help support weight gain and size goals
Complement intense training and high-output lifestyles
Provide a convenient mass gainer shake option

Key Benefits of Optimum Nutrition Serious Mass

High-Calorie Formula – Designed to support weight and size goals
Protein + Carbohydrate Blend – Supports muscle nutrition and energy needs
Convenient Shake Format – Easier than eating multiple large meals
Versatile Use – Can be taken post-workout or between meals
Trusted Brand – Optimum Nutrition is globally recognized for quality

Who Is Serious Mass Best For?

This mass gainer is ideal for:

Hard-gainers struggling to gain weight
Athletes with high calorie requirements
Individuals focused on size and mass support
Those looking to supplement meals with extra calories

How to Use Optimum Nutrition Serious Mass

Mix 1 serving with water, milk, or your preferred beverage.
Can be used:

Post-workout, or
Between meals to increase daily calorie intake

Adjust serving size based on individual nutrition needs.

Why Buy Optimum Nutrition Serious Mass from Bulldog Nutrition?

100% authentic supplements and 100% authorized retailer
Fast shipping across Canada
Earn Bulldog Credit Rewards on every order
Trusted online supplement retailer with expert support by Canadians

Product Highlights

Category: Mass Gainer
Format: Powder
Size: 6lbs
Use: Weight gain, calorie support, size goals
Lifestyle: High-output, strength & mass-focused training

Shipping Information

Bulldog Nutrition ships across Canada and the United States. Most orders are processed within 1 to 2 business days.

Free shipping is available on eligible orders over $100. Please note that drink cases are excluded from free shipping due to size and weight.

During extreme hot or cold weather, heat-sensitive or cold-sensitive items may be affected in transit. For full details, please review our Shipping Policy.

Product & Site Disclaimer

Website information is provided for general informational purposes only. Product details, images, ingredients, and labels may change without notice, so customers should always review the actual product packaging received before use. For full details, please review our Product & Site Disclaimer.

Need Help?

For the fastest assistance, please use Live Chat on our website. You can also text SUPPORT to 1-833-497-3885 or use our Contact Us page for order, shipping, returns, and general support questions.

Frequently Asked Questions

What is Optimum Serious Mass designed for?

It's designed to support weight gain and size goals for active individuals.

What are the key components of Serious Mass?

It contains calories, protein, carbohydrates, and added nutrients.

Who can benefit from using Serious Mass?

It's ideal for hard-gainers and those with high energy demands.

[{"id":47568962814197,"title":"Chocolate","option1":"Chocolate","option2":null,"option3":null,"sku":"13020","requires_shipping":true,"taxable":true,"featured_image":{"id":47286787506421,"product_id":9504556286197,"position":1,"created_at":"2026-01-29T14:42:15-05:00","updated_at":"2026-01-29T14:42:17-05:00","alt":"Optimum_Serious_Mass_6lbs_Chocolate_Canada","width":1200,"height":1200,"src":"\/\/www.bulldognutrition.com\/cdn\/shop\/files\/Optimum_Serious_Mass_6lbs_Chocolate_Canada.jpg?v=1769715737","variant_ids":[47568962814197]},"available":true,"name":"Optimum Serious Mass 6lbs - Chocolate","public_title":"Chocolate","options":["Chocolate"],"price":6997,"weight":2722,"compare_at_price":8995,"inventory_quantity":10,"inventory_management":"shopify","inventory_policy":"deny","barcode":"748927022995","featured_media":{"alt":"Optimum_Serious_Mass_6lbs_Chocolate_Canada","id":38236225962229,"position":1,"preview_image":{"aspect_ratio":1.0,"height":1200,"width":1200,"src":"\/\/www.bulldognutrition.com\/cdn\/shop\/files\/Optimum_Serious_Mass_6lbs_Chocolate_Canada.jpg?v=1769715737"}},"requires_selling_plan":false,"selling_plan_allocations":[]},{"id":47568966254837,"title":"Vanilla","option1":"Vanilla","option2":null,"option3":null,"sku":"13021","requires_shipping":true,"taxable":true,"featured_image":{"id":47286791143669,"product_id":9504556286197,"position":2,"created_at":"2026-01-29T14:43:54-05:00","updated_at":"2026-01-29T14:43:55-05:00","alt":"Optimum_Serious_Mass_6lbs_Vanilla_Canada","width":1200,"height":1200,"src":"\/\/www.bulldognutrition.com\/cdn\/shop\/files\/Optimum_Serious_Mass_6lbs_Vanilla_Canada.jpg?v=1769715835","variant_ids":[47568966254837]},"available":true,"name":"Optimum Serious Mass 6lbs - Vanilla","public_title":"Vanilla","options":["Vanilla"],"price":6997,"weight":2722,"compare_at_price":8995,"inventory_quantity":6,"inventory_management":"shopify","inventory_policy":"deny","barcode":"748927023008","featured_media":{"alt":"Optimum_Serious_Mass_6lbs_Vanilla_Canada","id":38236229533941,"position":2,"preview_image":{"aspect_ratio":1.0,"height":1200,"width":1200,"src":"\/\/www.bulldognutrition.com\/cdn\/shop\/files\/Optimum_Serious_Mass_6lbs_Vanilla_Canada.jpg?v=1769715835"}},"requires_selling_plan":false,"selling_plan_allocations":[]}]

{"id":47568962814197,"title":"Chocolate","option1":"Chocolate","option2":null,"option3":null,"sku":"13020","requires_shipping":true,"taxable":true,"featured_image":{"id":47286787506421,"product_id":9504556286197,"position":1,"created_at":"2026-01-29T14:42:15-05:00","updated_at":"2026-01-29T14:42:17-05:00","alt":"Optimum_Serious_Mass_6lbs_Chocolate_Canada","width":1200,"height":1200,"src":"\/\/www.bulldognutrition.com\/cdn\/shop\/files\/Optimum_Serious_Mass_6lbs_Chocolate_Canada.jpg?v=1769715737","variant_ids":[47568962814197]},"available":true,"name":"Optimum Serious Mass 6lbs - Chocolate","public_title":"Chocolate","options":["Chocolate"],"price":6997,"weight":2722,"compare_at_price":8995,"inventory_quantity":10,"inventory_management":"shopify","inventory_policy":"deny","barcode":"748927022995","featured_media":{"alt":"Optimum_Serious_Mass_6lbs_Chocolate_Canada","id":38236225962229,"position":1,"preview_image":{"aspect_ratio":1.0,"height":1200,"width":1200,"src":"\/\/www.bulldognutrition.com\/cdn\/shop\/files\/Optimum_Serious_Mass_6lbs_Chocolate_Canada.jpg?v=1769715737"}},"requires_selling_plan":false,"selling_plan_allocations":[]}