Is it better to take mass gainer before or after a workout?

October 20, 2025 •

5 min read

According to nutrition experts, mass gainers can provide a convenient and effective way to achieve the calorie surplus required for muscle growth, particularly for 'hardgainers'. However, the key question for many is finding the optimal timing, and whether it is better to take a mass gainer before or after a workout for maximum benefit.

Quick Summary

Mass gainers are calorie-dense supplements designed to help build muscle mass and weight. While both pre- and post-workout timing offers distinct advantages, taking a mass gainer after a workout is often prioritized for recovery and muscle protein synthesis.

Key Points

Post-Workout is Optimal for Recovery: For most people, taking a mass gainer after a workout is best for muscle protein synthesis and replenishing glycogen stores.
Pre-Workout is for Fueling Performance: A shake consumed 1-1.5 hours before training provides energy and helps prevent muscle breakdown during intense sessions.
Timing Depends on Your Goal: Your specific needs, whether for recovery, constant calorie intake, or performance, will determine the most strategic timing.
Consistency is More Important Than Timing: Adhering to a consistent intake and training schedule is the most significant factor for achieving results with a mass gainer.
Supplement, Don't Replace Meals: A mass gainer should always complement, not substitute, a balanced diet of whole foods for comprehensive nutrition.
Consider Other Timing for Calorie Needs: Taking a shake in the morning, between meals, or before bed can help hardgainers or those with high-calorie needs meet their daily targets.
Risk of GI Discomfort Pre-Workout: A large serving of mass gainer taken too close to a workout can lead to bloating or stomach upset, potentially hindering performance.

What is a Mass Gainer?

Before diving into the timing, it's crucial to understand what a mass gainer is and what it does. Mass gainers are high-calorie supplements formulated with a blend of protein, carbohydrates, and fats to help individuals increase their daily calorie and macronutrient intake. Unlike regular protein powders, which are primarily focused on protein, mass gainers have a higher carbohydrate and calorie count. Their primary purpose is to help people, especially those with fast metabolisms who struggle to eat enough whole foods, enter a consistent caloric surplus to support weight and muscle gain. However, to ensure this calorie surplus contributes to muscle rather than fat, it must be paired with consistent resistance training.

The Case for Post-Workout Mass Gainer

For most fitness enthusiasts, taking a mass gainer immediately after a workout is considered the most effective strategy. This is because the post-workout period, often referred to as the "anabolic window," is when your muscles are most receptive to nutrients. During intense exercise, your muscles undergo microscopic tears and deplete their stored energy (glycogen).

By consuming a mass gainer shake within 30-60 minutes after training, you can:

Enhance Muscle Protein Synthesis (MPS): The protein component of the gainer provides the amino acids needed to kickstart the repair and rebuilding of muscle tissue.
Replenish Glycogen Stores: The high carbohydrate content quickly restores muscle glycogen levels, providing energy for your next workout and preventing muscle breakdown (catabolism).
Accelerate Recovery: A quick supply of nutrients helps reduce muscle soreness and speeds up the overall recovery process.
Improve Nutrient Absorption: The increased blood flow to muscles after exercise enhances the absorption of nutrients.

The Case for Pre-Workout Mass Gainer

While less common, a mass gainer can also be consumed before a workout, provided there is enough time for digestion. This approach is primarily focused on fueling performance and preventing muscle breakdown during a long or intense session. However, timing is key to avoid stomach discomfort, and it is recommended to consume it 1-1.5 hours before training.

Benefits of a pre-workout mass gainer include:

Increased Energy Levels: The carbohydrates act as a fuel source to power you through your workout, boosting energy and preventing early fatigue.
Improved Endurance: Keeping your energy levels high can help you perform longer and more challenging workout sessions.
Muscle Preservation: The protein and amino acids can help reduce the rate of muscle breakdown that occurs during strenuous exercise.

Other Strategic Timing Options

Supplementing your mass gainer at other times throughout the day can also help meet your calorie goals and support muscle growth.

In the Morning

Taking a mass gainer in the morning, especially after fasting overnight, can help shift your body into an anabolic (muscle-building) state. It provides a quick and calorie-dense way to kickstart your metabolism and ensure you don't start the day in a calorie deficit.

Between Meals

For hardgainers who struggle to eat large meals, a mass gainer can be a convenient snack between meals to boost overall calorie intake. This helps maintain a constant supply of nutrients to your muscles throughout the day, which is crucial for staying in a caloric surplus.

Before Bed

Taking a mass gainer before bed, particularly one with a blend that includes slow-digesting proteins like casein, can provide a steady release of amino acids to your muscles overnight. This can help prevent muscle breakdown while you sleep, supporting recovery and growth.

Mass Gainer Before vs. After a Workout: A Comparison

To help you decide, here is a comparison of the primary benefits and considerations for taking a mass gainer before or after your training session.


Aspect	Before a Workout	After a Workout
Primary Goal	Fuel performance, boost endurance, preserve muscle.	Enhance muscle recovery, replenish glycogen, boost protein synthesis.
Timing	1-1.5 hours before training to allow for digestion.	Within 30-60 minutes after training to maximize the "anabolic window".
Carb Source	A blend of complex and simple carbs for sustained and immediate energy.	Primarily fast-digesting carbs to quickly replenish glycogen.
Protein Digestion	A mix of fast and slow-digesting protein can be beneficial to sustain amino acid supply.	Fast-digesting protein like whey is ideal to quickly supply muscles with amino acids.
Potential Downside	Can cause stomach discomfort or bloating, affecting workout performance.	Delayed intake can reduce the effectiveness of recovery.

How to Maximize Your Mass Gainer Results

Beyond timing, several other factors contribute to the effectiveness of a mass gainer.

Pair with Proper Training: A mass gainer is a supplement, not a magic bullet. For the calories to fuel muscle growth, you must consistently engage in a proper resistance training program.
Prioritize Whole Foods: While convenient, a mass gainer should complement, not replace, a balanced diet of whole foods. The bulk of your nutrients should still come from regular meals.
Stay Hydrated: Consuming enough water is essential for muscle growth and recovery, and it helps with the digestion of a high-calorie supplement.
Monitor Progress and Intake: Keep track of your weight and physique changes. Adjust your mass gainer dosage and overall calorie intake to ensure you're gaining muscle and not excessive fat.
Use High-Quality Supplements: Not all mass gainers are created equal. Choose a product with a high-quality blend of proteins, complex carbs, and minimal added sugars to avoid unwanted fat gain and digestive issues. You can find detailed breakdowns from independent reviews to help you decide.

Conclusion: When Is It Best for You?

There is no single correct answer to the question of whether it's better to take a mass gainer before or after a workout. The most beneficial timing depends on your individual goals and tolerance. For most people, consuming a mass gainer post-workout is the priority, as it is the most effective time to kickstart muscle recovery and growth by replenishing glycogen and boosting protein synthesis. However, if you are a hardgainer needing a consistent caloric intake or an athlete with high energy demands, incorporating a shake both before and after your workout, or at other points throughout the day, can be highly effective. Ultimately, consistency with both your mass gainer intake and your training is the most critical factor for achieving your mass gain goals.

Frequently Asked Questions

On rest days, the purpose of a mass gainer is to maintain a caloric surplus to support muscle growth and prevent catabolism. You can take it in the morning to kickstart your day, or between meals to fill calorie gaps, especially if you have a fast metabolism.

Yes, many mass gainers already contain creatine. Taking creatine with carbohydrates, which a mass gainer provides, can improve its absorption into the muscles. If your gainer does not contain creatine, you can add it to your post-workout shake.

Using milk will increase the calories, protein, and fat content of your shake, which can be beneficial for hardgainers trying to maximize their calorie intake. Water is a good option for a lower-calorie, faster-digesting shake, especially if you have lactose intolerance.

Taking a mass gainer before bed can provide a slow release of nutrients for overnight muscle recovery, but it is not recommended if you have already met your daily calorie needs. If you choose to, consider a blend with casein protein and monitor your intake to avoid unwanted fat gain.

The 'anabolic window' is the period after exercise, typically 30-60 minutes, during which your muscles are most receptive to nutrients. Consuming a blend of protein and carbohydrates during this time is believed to maximize muscle repair and growth.

Yes, a mass gainer is a supplement and should not replace a balanced, whole-food diet. Whole foods provide essential vitamins, minerals, and fiber that are often lacking in supplements.

To minimize bloating, start with a smaller serving size and gradually increase it as your body adapts. Ensuring adequate hydration and choosing a high-quality mass gainer with digestive enzymes can also help.