How much protein do I actually need to maintain muscle? A comprehensive guide

November 11, 2025 •

4 min read

The recommended dietary allowance (RDA) for protein is 0.8 grams per kilogram of body weight, but this amount is insufficient for active individuals looking to maintain muscle. Determining how much protein do I actually need to maintain muscle depends on multiple factors beyond the minimum requirement.

Quick Summary

This guide outlines optimal daily protein intake ranges based on activity level, age, and individual goals to effectively preserve lean muscle mass. It details calculation methods, the importance of timing and quality, and provides a comparative table and list of food sources.

Key Points

Optimal Intake Range: Most active adults and older individuals should aim for 1.2 to 2.2 grams of protein per kilogram of body weight daily, exceeding the minimum RDA.
Timing Matters Less than Total Intake: While the 'anabolic window' is less critical than once thought, distributing 20–40 grams of protein across 4-5 meals helps optimize muscle protein synthesis.
Older Adults Need More Protein: Individuals over 65 have higher protein requirements, from 1.2 to 1.6 g/kg, to counteract anabolic resistance and prevent muscle loss.
Protein Quality is Crucial: Prioritize complete protein sources, such as lean meats, eggs, and dairy, or combine various plant-based foods to get all essential amino acids.
Pair with Resistance Training: Diet is only half the strategy; consistent resistance exercise is essential to stimulate muscle protein synthesis and maintain muscle mass.
Beware of Excess Calories: While a high-protein diet is effective, consuming too much protein can contribute to excess calorie intake and potential fat gain if not managed properly.

Understanding Your Protein Needs

Protein is a crucial macronutrient composed of amino acids, the building blocks for muscle tissue. While muscle growth (hypertrophy) receives most of the attention, maintaining muscle mass is an equally important—and often overlooked—aspect of health and fitness. Sarcopenia, the age-related loss of muscle mass, can be significantly mitigated with adequate protein intake and regular resistance training. Proper protein consumption helps to repair and regenerate muscle fibers, preventing atrophy and supporting overall metabolic function.

Calculating Your Optimal Protein Intake

Your specific protein requirement is not a one-size-fits-all number. It varies considerably based on your body weight, activity level, and age. The standard RDA of 0.8g/kg is merely the minimum to prevent deficiency in sedentary adults, not the optimal amount for active people. More nuanced guidelines suggest a higher intake for those who exercise regularly.

To calculate your needs, follow these steps:

Find your weight in kilograms. If you know your weight in pounds, divide it by 2.2 to get your weight in kilograms. For example, a 180-pound person weighs approximately 81.8 kg.
Determine your activity level. Are you sedentary, moderately active, or a dedicated athlete?
Multiply your weight by the recommended range. Multiply your weight in kg by the appropriate protein range to find your daily intake goal.

Protein Needs Based on Activity Level

Research and expert recommendations suggest varying protein intake levels for different lifestyles. A meta-analysis concluded that total daily intake is the most important factor, outweighing the strict timing of a post-workout 'anabolic window'.

Guidelines by Activity Level

Sedentary Adults: Aim for at least 1.2 grams per kilogram of body weight. This is a baseline recommendation to maintain lean mass and overall health.
Moderately Active Individuals: For those who exercise regularly, aim for 1.2 to 1.6 grams per kilogram. This range supports muscle repair and maintenance.
Athletes and Intense Trainers: Highly active individuals may need up to 1.6 to 2.2 grams per kilogram, depending on training intensity and goals. Those in a caloric deficit may need to aim for the higher end to preserve muscle.
Older Adults (65+): Due to a phenomenon called anabolic resistance, older individuals need more protein to achieve the same muscle-building response as younger people. The recommendation is 1.2 to 1.6 grams per kilogram to combat sarcopenia.

The Importance of Consistent Intake

While the concept of an immediate post-workout 'anabolic window' has been challenged, distributing your protein intake evenly throughout the day remains a beneficial strategy. Studies suggest that consuming approximately 20–40 grams of high-quality protein per meal or snack helps to maximize muscle protein synthesis. This consistent supply of amino acids throughout the day keeps your body in an optimal state for muscle repair and maintenance.

Protein Sources: Quality and Variety

Not all protein is created equal. Complete proteins contain all nine essential amino acids necessary for muscle repair. Animal-based sources are typically complete, while many plant-based options are incomplete and should be combined strategically to ensure a full amino acid profile.

High-Quality Protein Sources

Animal-Based:
- Chicken breast (very lean)
- Lean beef (sirloin, ground beef)
- Fish (salmon, tuna, cod)
- Eggs
- Dairy (Greek yogurt, cottage cheese, milk)
- Whey and Casein protein powders
Plant-Based:
- Soy products (tofu, tempeh, edamame)
- Lentils and beans
- Quinoa and buckwheat
- Nuts and seeds (hemp, chia, pumpkin)
- Spirulina
- Plant-based protein powders (pea, rice, hemp)

Protein Intake Comparison Table


Population Group	Activity Level	Recommended Protein Intake (g/kg/day)	Considerations
Healthy Adult	Sedentary	≥ 1.2	Baseline for general health, not optimal for muscle
Healthy Adult	Moderately Active	1.2 - 1.6	Supports muscle repair from regular exercise
Athlete	High Intensity	1.6 - 2.2	Higher end recommended during calorie deficits or intense training
Older Adult (65+)	All Levels	1.2 - 1.6	Compensates for anabolic resistance; paired with resistance training
Individual in Calorie Deficit	Active	1.6 - 2.4	Aims to preserve muscle mass while losing fat

Conclusion: Finding the Right Balance

The key to effective muscle maintenance is moving beyond the outdated standard RDA. By assessing your personal activity level, age, and goals, you can target a more appropriate protein intake, typically in the range of 1.2 to 2.2 grams per kilogram of body weight per day. Focusing on high-quality, varied protein sources and distributing your intake across several meals will maximize muscle protein synthesis and help preserve your hard-earned muscle mass. Remember that diet is only one part of the equation; pairing sufficient protein with regular resistance exercise is the most effective strategy for maintaining muscle throughout your life. For personalized guidance, consulting with a registered dietitian can provide tailored recommendations based on your unique health profile. Learn more about the factors influencing your protein needs from this comprehensive guide by Examine.com(https://examine.com/guides/protein-intake/).

Frequently Asked Questions

Building muscle (hypertrophy) generally requires a higher protein intake, typically 1.6–2.2 g/kg, combined with a caloric surplus. For muscle maintenance, especially in active individuals, a slightly lower but still elevated intake of around 1.2–1.6 g/kg is often sufficient to prevent muscle breakdown.

For most active individuals and older adults, no. The official RDA is the minimum required to prevent deficiency in sedentary adults and is not optimized for supporting exercise, muscle repair, or preventing age-related muscle loss.

The total amount of protein consumed daily is more important than the exact timing. However, distributing protein intake evenly throughout the day, with 20–40 grams per meal, is a good strategy to maximize muscle protein synthesis.

Yes, older adults need a higher protein intake, typically 1.2–1.6 g/kg, to overcome anabolic resistance. This helps their bodies more effectively utilize protein to maintain muscle mass and strength as they age.

Yes, it is possible. While many plant proteins are incomplete, combining a variety of plant-based sources like soy, legumes, grains, nuts, and seeds ensures you get all the essential amino acids needed for muscle maintenance.

If your protein intake is consistently insufficient, your body may start to break down muscle tissue to get the amino acids it needs. Over time, this can lead to a loss of muscle mass, decreased strength, and a slower metabolism.

No, supplements are not mandatory. You can meet your protein goals through whole foods. Supplements like protein powders can be a convenient and effective tool, especially for those with high protein needs or busy schedules.