{"id":4192,"date":"2026-04-23T15:10:05","date_gmt":"2026-04-23T15:10:05","guid":{"rendered":"https:\/\/www.muscle-madness.co.uk\/store\/?post_type=product&p=4192"},"modified":"2026-04-23T15:30:49","modified_gmt":"2026-04-23T15:30:49","slug":"optimum-nutrition-serious-mass-weight-gainer-2-73kg","status":"publish","type":"product","link":"https:\/\/www.muscle-madness.co.uk\/store\/product\/optimum-nutrition-serious-mass-weight-gainer-2-73kg\/","title":{"rendered":"Optimum Nutrition SERIOUS MASS Weight Gainer 2.73kg"},"content":{"rendered":"
SERIOUS MASS Weight Gainer 2.73kg<\/h5>\n
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Serious Mass is a high-calorie weight gain formula designed to help individuals increase their daily caloric intake, supporting their training and nutrition goals. Each serving provides 1,250 calories, 50 grams of protein, over 250 grams of carbohydrates, and 3 grams of added creatine to enhance performance.<\/p>\n

Performance Benefits:<\/strong><\/h5>\n
    \n
  • Delivers 1,250 calories per serving to assist in achieving a calorie surplus, essential for weight gain and muscle development.<\/li>\n
  • Contains 50 grams of whey protein per serving to support muscle growth and maintenance.<\/li>\n
  • Offers over 250 grams of carbohydrates per serving to aid in muscle recovery and replenish glycogen stores after intense workouts.<\/li>\n
  • Includes 3 grams of added creatine per serving to support improved performance during high-intensity exercise.<\/li>\n<\/ul>\n
    When to Use This Product:<\/h5>\n
      \n
    • Post-Workout: Consume within 30 minutes after exercise to support muscle recovery and replenish energy stores.<\/li>\n
    • Between Meals: Use as a high-calorie snack to maintain a positive energy balance and support continuous muscle growth.<\/li>\n
    • Before Bed: Take before sleep to provide a steady supply of nutrients during the overnight fasting period.<\/li>\n<\/ul>\n

      Serious Mass is ideal for individuals with a high metabolism, a weaker appetite, or those leading an on-the-go lifestyle who find it challenging to consume sufficient calories through whole foods alone. Available in a range of great-tasting flavours, it provides a convenient and effective solution to support your weight gain and muscle-building goals.<\/p>\n

      *Carbohydrates contribute to the recovery of normal muscle function after highly intensive and\/or long-lasting physical exercise leading to muscle fatigue and the depletion of glycogen stores in skeletal muscle. This benefit is observed with an intake of total carbohydrates at 4 g per kg body weight, at doses, within the first 4-6 hours.
      \n*Protein contributes to growth and maintenance of muscle mass with regular weights resistance training.<\/small><\/p>\n

      Suggested Use:<\/strong><\/p>\n

      Mix 2 heaped scoops with 710 ml of water. You can also add a serving to smoothies, protein balls, muffins, porridge or other meals as another great way to get a protein hit in the kitchen.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

      \n
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      • The ultimate weight gainer powder, ideal for post-workout or between meals, to support muscle building and weight gain.<\/li>\n
      • Provides over 1,250 kcal per serving to fuel your goals.<\/li>\n
      • Contains 50g of high-quality whey protein and 251g of carbohydrates per serving\u2014formulated to support your nutritional strategy around training and overall energy intake.<\/li>\n
      • Includes 25 essential vitamins and minerals to support overall health and performance.<\/li>\n
      • Mix 2 scoops with 710 ml of water or milk for a rich and effective weight-gainer shake.<\/li>\n<\/ul>\n
        CHOOSE FLAVOUR:<\/h5>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"featured_media":4199,"comment_status":"open","ping_status":"closed","template":"","meta":[],"product_brand":[],"product_cat":[154,98,595],"product_tag":[150,338,151,233,563,152,313,342,146],"class_list":{"0":"post-4192","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-brands","7":"product_cat-mass-gainer","8":"product_cat-optimum_nutrition","9":"product_tag-amino-acid","10":"product_tag-carbohydrates","11":"product_tag-creatine","12":"product_tag-health","13":"product_tag-mass","14":"product_tag-mass-gainer","15":"product_tag-muscle","16":"product_tag-protein","17":"product_tag-supplement","19":"first","20":"instock","21":"shipping-taxable","22":"purchasable","23":"product-type-variable"},"yoast_head":"\nOptimum Nutrition SERIOUS MASS Weight Gainer 2.73kg - Muscle and Madness Supplement Store<\/title>\n<meta name=\"description\" content=\"SERIOUS MASS Weight Gainer 2.73kg Serious Mass is a high-calorie weight gain formula designed to help individuals increase their daily caloric intake, supporting their training and nutrition goals. Each serving provides 1,250 calories, 50 grams of protein, over 250 grams of carbohydrates, and 3 grams of added creatine to enhance performance. Performance Benefits: Delivers 1,250 calories per serving to assist in achieving a calorie surplus, essential for weight gain and muscle development. Contains 50 grams of whey protein per serving to support muscle growth and maintenance. Offers over 250 grams of carbohydrates per serving to aid in muscle recovery and replenish glycogen stores after intense workouts. Includes 3 grams of added creatine per serving to support improved performance during high-intensity exercise. When to Use This Product: Post-Workout: Consume within 30 minutes after exercise to support muscle recovery and replenish energy stores. Between Meals: Use as a high-calorie snack to maintain a positive energy balance and support continuous muscle growth. Before Bed: Take before sleep to provide a steady supply of nutrients during the overnight fasting period. Serious Mass is ideal for individuals with a high metabolism, a weaker appetite, or those leading an on-the-go lifestyle who find it challenging to consume sufficient calories through whole foods alone. Available in a range of great-tasting flavours, it provides a convenient and effective solution to support your weight gain and muscle-building goals.*Carbohydrates contribute to the recovery of normal muscle function after highly intensive and\/or long-lasting physical exercise leading to muscle fatigue and the depletion of glycogen stores in skeletal muscle. This benefit is observed with an intake of total carbohydrates at 4 g per kg body weight, at doses, within the first 4-6 hours.*Protein contributes to growth and maintenance of muscle mass with regular weights resistance training. Suggested Use: Mix 2 heaped scoops with 710 ml of water. You can also add a serving to smoothies, protein balls, muffins, porridge or other meals as another great way to get a protein hit in the kitchen.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.muscle-madness.co.uk\/store\/product\/optimum-nutrition-serious-mass-weight-gainer-2-73kg\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Optimum Nutrition SERIOUS MASS Weight Gainer 2.73kg - Muscle and Madness Supplement Store\" \/>\n<meta property=\"og:description\" content=\"SERIOUS MASS Weight Gainer 2.73kg Serious Mass is a high-calorie weight gain formula designed to help individuals increase their daily caloric intake, supporting their training and nutrition goals. Each serving provides 1,250 calories, 50 grams of protein, over 250 grams of carbohydrates, and 3 grams of added creatine to enhance performance. Performance Benefits: Delivers 1,250 calories per serving to assist in achieving a calorie surplus, essential for weight gain and muscle development. Contains 50 grams of whey protein per serving to support muscle growth and maintenance. Offers over 250 grams of carbohydrates per serving to aid in muscle recovery and replenish glycogen stores after intense workouts. Includes 3 grams of added creatine per serving to support improved performance during high-intensity exercise. When to Use This Product: Post-Workout: Consume within 30 minutes after exercise to support muscle recovery and replenish energy stores. Between Meals: Use as a high-calorie snack to maintain a positive energy balance and support continuous muscle growth. Before Bed: Take before sleep to provide a steady supply of nutrients during the overnight fasting period. Serious Mass is ideal for individuals with a high metabolism, a weaker appetite, or those leading an on-the-go lifestyle who find it challenging to consume sufficient calories through whole foods alone. Available in a range of great-tasting flavours, it provides a convenient and effective solution to support your weight gain and muscle-building goals.*Carbohydrates contribute to the recovery of normal muscle function after highly intensive and\/or long-lasting physical exercise leading to muscle fatigue and the depletion of glycogen stores in skeletal muscle. This benefit is observed with an intake of total carbohydrates at 4 g per kg body weight, at doses, within the first 4-6 hours.*Protein contributes to growth and maintenance of muscle mass with regular weights resistance training. Suggested Use: Mix 2 heaped scoops with 710 ml of water. You can also add a serving to smoothies, protein balls, muffins, porridge or other meals as another great way to get a protein hit in the kitchen.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.muscle-madness.co.uk\/store\/product\/optimum-nutrition-serious-mass-weight-gainer-2-73kg\/\" \/>\n<meta property=\"og:site_name\" content=\"Muscle and Madness Supplement Store\" \/>\n<meta property=\"article:modified_time\" content=\"2026-04-23T15:30:49+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.muscle-madness.co.uk\/store\/wp-content\/uploads\/2026\/04\/Optimum-Nutrition-SERIOUS-MASS-Weight-Gainer-2.73kg-Chocolate.png\" \/>\n\t<meta property=\"og:image:width\" content=\"1080\" \/>\n\t<meta property=\"og:image:height\" content=\"1080\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.muscle-madness.co.uk\/store\/product\/optimum-nutrition-serious-mass-weight-gainer-2-73kg\/\",\"url\":\"https:\/\/www.muscle-madness.co.uk\/store\/product\/optimum-nutrition-serious-mass-weight-gainer-2-73kg\/\",\"name\":\"Optimum Nutrition SERIOUS MASS Weight Gainer 2.73kg - Muscle and Madness Supplement Store\",\"isPartOf\":{\"@id\":\"https:\/\/www.muscle-madness.co.uk\/store\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/www.muscle-madness.co.uk\/store\/product\/optimum-nutrition-serious-mass-weight-gainer-2-73kg\/#primaryimage\"},\"image\":{\"@id\":\"https:\/\/www.muscle-madness.co.uk\/store\/product\/optimum-nutrition-serious-mass-weight-gainer-2-73kg\/#primaryimage\"},\"thumbnailUrl\":\"https:\/\/www.muscle-madness.co.uk\/store\/wp-content\/uploads\/2026\/04\/Optimum-Nutrition-SERIOUS-MASS-Weight-Gainer-2.73kg-Chocolate.png\",\"datePublished\":\"2026-04-23T15:10:05+00:00\",\"dateModified\":\"2026-04-23T15:30:49+00:00\",\"description\":\"SERIOUS MASS Weight Gainer 2.73kg Serious Mass is a high-calorie weight gain formula designed to help individuals increase their daily caloric intake, supporting their training and nutrition goals. 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Serious Mass is ideal for individuals with a high metabolism, a weaker appetite, or those leading an on-the-go lifestyle who find it challenging to consume sufficient calories through whole foods alone. Available in a range of great-tasting flavours, it provides a convenient and effective solution to support your weight gain and muscle-building goals.*Carbohydrates contribute to the recovery of normal muscle function after highly intensive and\/or long-lasting physical exercise leading to muscle fatigue and the depletion of glycogen stores in skeletal muscle. This benefit is observed with an intake of total carbohydrates at 4 g per kg body weight, at doses, within the first 4-6 hours.*Protein contributes to growth and maintenance of muscle mass with regular weights resistance training. Suggested Use: Mix 2 heaped scoops with 710 ml of water. 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