Can Omega-3 Boost Muscle Protein Synthesis? What the Latest Research Reveals

For years, omega-3 fatty acids were confined to the cardiovascular conversation — prescribed for triglycerides, discussed in the context of arrhythmia risk, and marketed for “heart health.” But a quiet shift has been unfolding in exercise physiology and aging research. Skeletal muscle — not the heart — is rapidly becoming the new frontier of omega-3 science. Between 2024 and 2026, a wave of peer-reviewed investigations has reframed EPA and DHA not merely as anti-inflammatory lipids, but as active modulators of muscle protein synthesis, mitochondrial efficiency, vascular perfusion, and exercise adaptation (Hayden & Deane, 2026; Karimi et al., 2025).

This shift matters. After the age of 30, adults lose approximately 3–8% of muscle mass per decade, a trajectory that accelerates with aging and chronic disease. The biological culprit is not simply inactivity, but anabolic resistance — a blunted muscle response to amino acids and insulin. Emerging evidence suggests omega-3 fatty acids may partially restore this sensitivity by enhancing mTORC1 signaling and improving microvascular nutrient delivery (Karimi et al., 2025; Uchida et al., 2024).

Yet the evidence is not uniformly positive. Strength gains appear modest and population-dependent, with the most consistent benefits observed in older or untrained individuals rather than elite athletes (Tomczyk, 2024). Furthermore, EPA and DHA may exert distinct physiological effects during exercise, challenging the long-standing assumption that they are metabolically interchangeable (Blannin et al., 2025).

The question, then, is no longer whether omega-3s are “good for you.” It is far more precise: can they meaningfully influence skeletal muscle biology across the lifespan?

Clinical pearls.

1. The "Anabolic Sensitizer" Effect

• Scientific Perspective: Omega-3s (EPA/DHA) are incorporated into the phospholipid bilayer of muscle cells, enhancing the sensitivity of the mTORC1 signaling pathway to amino acids and insulin.

• Think of Omega-3s as "tuning" your muscles' ears. They help your muscles "hear" the signal from the protein you eat and the weights you lift, making your body more efficient at building and repairing tissue.

2. Overcoming "Anabolic Resistance" in Aging

• Scientific Perspective: Aging is characterized by a blunted protein synthesis response to nutrition. Omega-3 supplementation can partially reverse this "anabolic resistance" by reducing chronic low-grade inflammation and improving signaling efficiency.

• As we get older, our muscles often become "stubborn" and don't respond to exercise as well as they used to. Omega-3s act like a lubricant for that process, helping older muscles react more like younger ones when you stay active.

3. The "Vascular-Mediated Anabolism" Pathway

• Scientific Perspective: Omega-3s promote the production of resolvins and nitric oxide, which enhance microvascular blood flow (vasodilation), ensuring better delivery of glucose and amino acids to muscle fibers post-exercise.

• It’s not just about what you eat; it’s about getting those nutrients to the muscle. Omega-3s help "open up the highways" (your blood vessels) so that the building blocks from your meals can actually reach the muscles that need them.

4. EPA vs. DHA: Specificity of Function

• Scientific Perspective: EPA and DHA are not metabolically interchangeable. DHA appears to have a more pronounced effect on cardiac efficiency and oxygen kinetics, while EPA exerts a more potent systemic anti-inflammatory influence.

• Not all fish oils are the same. If you are an endurance athlete (like a runner), you might want a supplement higher in DHA for heart efficiency. If you are dealing with joint pain or heavy recovery needs, an EPA-rich version might be better for cooling inflammation.

5. Synergistic Adaptation, Not a Solo Act

• Scientific Perspective: Omega-3s do not significantly increase maximal strength or hypertrophy in isolation for well-trained individuals. The benefit is synergistic, meaning they amplify the adaptive response only when paired with resistance training.

• Omega-3s are an "amplifier," not a "replacement." Taking the supplement while sitting on the couch won't build muscle, but taking it while you are consistent with your 30-minute workouts will help you see results faster and recover more easily.

6. The "Saturation Window" (Consistency over Timing)

• Scientific Perspective: Meaningful changes in muscle physiology require the incorporation of fatty acids into cell membranes, which takes 8–12 weeks of consistent dosing (2–4g/day) to reach a steady state.

• Don't expect a "pre-workout" miracle. Unlike caffeine, which works in 20 minutes, Omega-3s are a long-term investment. You need to take them daily for about three months before your muscle cells are fully "upgraded."

Understanding the Biological Mechanisms: Setting the Stage

Before diving into individual studies, it helps to understand the landscape of how omega-3s interact with skeletal muscle biology. Skeletal muscle is a metabolically dynamic tissue — it is constantly being built up and broken down through a process known as protein turnover. In a healthy state, synthesis and breakdown are balanced. Disturbances to this balance — from aging, inactivity, or chronic disease — tip the scale toward muscle loss.

Omega-3 fatty acids, particularly EPA and DHA, are incorporated into cell membrane phospholipids, where they influence receptor sensitivity, inflammation signalling, and gene expression. They interact with the anabolic mTORC1 signalling pathway, modulate mitochondrial dynamics, and affect vascular responsiveness in ways that could, in theory, enhance nutrient delivery to muscle tissue. These mechanisms form the scientific foundation upon which current research is being built.

Study 1: Protein Turnover and Mitochondrial AdaptationSummary

This 2026 review from Hayden and Deane provides one of the most current summaries of how omega-3 supplementation influences two interrelated muscle processes: protein turnover and mitochondrial biogenesis. The authors draw on a wide body of experimental evidence to argue that EPA and DHA do not simply reduce inflammation — they actively participate in the regulation of muscle anabolic signalling and mitochondrial quality control.

The review emphasises that omega-3s may sensitise muscle tissue to anabolic stimuli such as insulin and amino acids, making them particularly relevant in populations with anabolic resistance — a condition common in older adults and those with chronic illness. The authors also discuss how omega-3 fatty acids influence mitochondrial membrane composition, potentially improving respiratory efficiency and reducing oxidative stress within muscle cells.

Importantly, Hayden and Deane acknowledge that translating these mechanistic insights into consistent clinical outcomes remains a challenge, with variability in dose, duration, form of omega-3, and study population all contributing to mixed results across trials.

🔑 Key Takeaway

Omega-3 supplementation appears to influence skeletal muscle biology at both the protein synthesis and mitochondrial levels, but individual response variability remains a key obstacle to establishing universal dosing recommendations.

Study 2: Vascular Health and Muscle Metabolism

Karimi and colleagues approach the omega-3–muscle connection from a vascular perspective, an angle that is often underrepresented in muscle physiology research. The premise of their 2025 review is straightforward but compelling: muscle performance and recovery are not purely cellular phenomena — they depend heavily on the delivery of oxygen, nutrients, and anabolic hormones through the vascular network feeding muscle tissue.

The authors document how omega-3 fatty acids exert vasodilatory effects through the production of resolvins, protectins, and nitric oxide-related pathways. These mechanisms improve microvascular blood flow within skeletal muscle, thereby enhancing the delivery of glucose, amino acids, and insulin to muscle fibres — a phenomenon the authors describe as vascular-mediated anabolism.

Karimi et al. highlight particularly interesting findings related to postprandial nutrient delivery. After a meal, muscle normally experiences a surge in blood flow that helps direct amino acids toward protein synthesis. This "vascular meal response" appears to be blunted in older adults and metabolically compromised individuals. Evidence reviewed by the authors suggests that omega-3 supplementation may restore or enhance this response, providing a vascular mechanism by which omega-3s could counter age-related muscle loss.

🔑 Key Takeaway

The muscle benefits of omega-3s may be partly mediated through improved microvascular blood flow, which enhances nutrient delivery to skeletal muscle — a mechanism especially relevant for older adults experiencing blunted postprandial anabolic responses.

Study 3: Omega-3s and Muscle Strength — What We Know and Where We Are Heading

Tomczyk's 2024 comprehensive review published in Nutrients tackles what many consider the most practically relevant question in this field: do omega-3 supplements actually make muscles stronger? The short answer, according to Tomczyk, is "possibly — but it depends."

The review synthesises data from randomised controlled trials, systematic reviews, and meta-analyses examining the effects of omega-3 supplementation on measures of muscle strength including grip strength, leg press performance, and isokinetic dynamometry. The findings reveal a pattern of modest but meaningful benefit, particularly when omega-3 supplementation is combined with resistance training rather than administered in isolation.

Tomczyk identifies several moderating variables that explain the inconsistency in findings across studies. Age is one of the strongest: older adults consistently show greater strength benefits from omega-3 supplementation than younger individuals, likely because they have more to gain from anti-inflammatory and anabolic sensitisation effects. Training status also matters — untrained individuals appear to respond more robustly than trained athletes. The review also highlights the critical role of dosage, with most positive outcomes associated with daily intakes of 2–4 grams of combined EPA and DHA over at least 8–12 weeks.

Future perspectives outlined by Tomczyk include the need for more studies using stable isotope tracer methodology to directly measure protein synthesis rates, as well as trials stratified by baseline omega-3 status, which can confound outcomes when all participants are treated identically regardless of dietary background.

🔑 Key Takeaway

Omega-3 supplementation shows the most consistent strength benefits in older or untrained individuals, particularly when combined with resistance training at doses of 2–4 g/day of EPA+DHA over 8–12 weeks; younger, well-trained populations appear less responsive.

Study 4: EPA vs. DHA — Are They Interchangeable?

One of the most practically impactful questions in omega-3 supplementation research is whether EPA and DHA produce different physiological outcomes — and if so, which one should practitioners and athletes prioritise. Blannin, Boulton, and Thielecke address this question directly in their 2025 intervention study, which stands out for comparing EPA-rich versus DHA-rich formulations in an active population.

The study enrolled endurance-trained male amateur athletes and randomly assigned them to six weeks of either EPA-rich or DHA-rich omega-3 supplementation. Submaximal exercise physiology was assessed at baseline and post-intervention using standardised cycling protocols. Both supplementation forms produced alterations in exercise physiology markers, but the nature of the effects differed between EPA and DHA, suggesting these fatty acids are not metabolically interchangeable despite both being classified as long-chain omega-3 polyunsaturated fatty acids.

While both groups showed improvements in some indicators of exercise economy, DHA supplementation appeared to produce more pronounced effects on heart rate and oxygen efficiency at submaximal intensities. EPA, on the other hand, appeared to exert stronger anti-inflammatory influence. The authors caution that their findings apply specifically to submaximal aerobic exercise in trained men and that generalisation to other populations or exercise types should be done carefully.

This study is significant because most commercial omega-3 supplements contain varying EPA:DHA ratios, and manufacturers rarely differentiate their products based on these ratios. The findings suggest that future product development and clinical guidance should consider the specific EPA and DHA content rather than treating omega-3s as a single monolithic category.

🔑 Key Takeaway

EPA and DHA produce distinct physiological effects during exercise: DHA appears more influential on oxygen efficiency and cardiac responses during submaximal aerobic effort, while EPA demonstrates stronger anti-inflammatory effects — suggesting these fatty acids should be considered separately, not interchangeably.

Study 5: Omega-3s and Resistance Training — A Combined Approach

While several studies examine omega-3 supplementation or resistance training in isolation, Uchida and colleagues focus their 2024 review specifically on the combined intervention — asking whether the two work synergistically to produce greater gains in muscle mass and strength than either alone. This is arguably the most practically applicable question for coaches, physiotherapists, and athletes who already have structured training programmes in place.

The review draws on data from multiple intervention studies and finds meaningful evidence that omega-3 supplementation can augment the adaptive response to resistance training. The proposed mechanisms include enhanced mTOR signalling (the primary anabolic pathway activated by both resistance exercise and amino acids), reduced exercise-induced inflammation, and improved satellite cell activity — the muscle stem cells responsible for muscle repair and growth.

Uchida et al. pay particular attention to the timing of supplementation relative to training. While the evidence is not definitive, some studies suggest that pre-exercise omega-3 ingestion may optimise the acute anabolic window by reducing inflammatory interference during the critical post-exercise recovery period. The authors also highlight that omega-3s may accelerate recovery from exercise-induced muscle damage, allowing athletes to train more frequently without compromising performance.

The study population most likely to benefit, according to this review, includes older adults undergoing strength training programmes, individuals recovering from orthopaedic injuries, and those in early-stage resistance training where anabolic sensitivity is highest.

🔑 Key Takeaway

Omega-3 supplementation and resistance training appear to work synergistically to enhance muscle protein synthesis and recovery, with the combination producing greater hypertrophic and strength adaptations than resistance training alone — particularly in older adults and rehabilitation populations.

Connecting the Dots: A Unified Picture of Omega-3 and Skeletal Muscle Science

1️⃣ Omega-3s Are No Longer Just “Heart Nutrients”

• For decades, omega-3 fatty acids (EPA and DHA) were primarily associated with cardiovascular protection.

• Emerging research now positions skeletal muscle as a major target tissue.

• The conversation has shifted from lipid panels to muscle physiology, aging, and exercise adaptation.

2️⃣ Skeletal Muscle Is a Metabolic Organ — Not Just a Movement Tissue

• Muscle regulates postprandial glucose disposal and metabolic rate.

• It acts as an endocrine organ influencing inflammatory tone.

• Age-related muscle decline (sarcopenia) contributes to frailty, insulin resistance, and loss of independence.

• Preserving muscle is central to extending healthspan, not merely lifespan.

3️⃣ Omega-3s Influence Muscle at Multiple Biological Levels

Cellular & Molecular

• Incorporation into muscle cell membranes alters signaling dynamics.

• May enhance mTORC1 activation and improve anabolic sensitivity.

• Potentially counteracts anabolic resistance seen with aging.

Mitochondrial Function

• Improve membrane fluidity and respiratory efficiency.

• May reduce oxidative stress and support mitochondrial quality control.

Vascular Mechanisms

• Enhance nitric oxide–mediated vasodilation.

• Improve microvascular blood flow.

• Facilitate nutrient and insulin delivery to skeletal muscle.

4️⃣ Strength Gains: Modest, Context-Dependent

• Benefits are most consistent in:

  • Older adults

  • Untrained individuals

  • Rehabilitation populations

• Effects in highly trained athletes are smaller and less predictable.

• Omega-3s amplify adaptation; they do not replace resistance training.

5️⃣ EPA and DHA Are Not Interchangeable

• EPA appears more strongly anti-inflammatory.

• DHA may more significantly influence submaximal exercise efficiency and cardiac responses.

• Supplement formulations and EPA: DHA ratios matter more than previously assumed.

6️⃣ Synergy With Resistance Training

• Evidence suggests greater hypertrophy and strength gains when omega-3s are combined with structured resistance training.

• May enhance anabolic signaling and recovery.

• Function best as an adjunct, not a standalone intervention

  .

7️⃣ Precision Matters

Effects depend on:

• Dose (commonly 2–4 g/day EPA+DHA)

• Duration (≥8–12 weeks)

• Age and training status

• Baseline omega-3 status

• Overall metabolic health

8️⃣ The Bottom Line

• Omega-3 fatty acids are multifaceted modulators of muscle biology.

• Their greatest value lies in supporting aging muscle, metabolic resilience, and structured training programs.

• They are neither miracle supplements nor trivial additions — but context-dependent tools in long-term muscle preservation.

Practical Implications: What Does This Mean for You?

For general health and muscle maintenance, the evidence supports omega-3 supplementation as a safe, accessible, and potentially beneficial addition to a balanced diet. For older adults or those in rehabilitation, the case is particularly compelling. For competitive athletes, the picture is more nuanced — submaximal exercise efficiency may improve (particularly with DHA-rich formulations), but the magnitude of strength gains in already well-trained individuals is modest.

Doses of 2–4 grams of combined EPA+DHA per day, maintained for at least 8–12 weeks, appear to fall within the range most consistently associated with beneficial outcomes in the reviewed literature. Supplementation should ideally be sustained rather than cyclic, given that omega-3 incorporation into cell membranes takes several weeks to stabilise.

Those considering supplementation should also attend to the EPA:DHA ratio in their chosen product, as the emerging evidence suggests these two fatty acids are not interchangeable. Fish oil, krill oil, and algae-based omega-3 supplements all vary considerably in their EPA:DHA composition, and informed product selection is warranted — particularly for endurance athletes where submaximal exercise efficiency is a performance priority.

Frequently Asked Questions (FAQs)

1. How much omega-3 do I need to see benefits for muscle health? Based on the reviewed literature, most studies reporting meaningful muscle-related benefits used doses of 2–4 grams of combined EPA+DHA per day. Lower doses may still confer cardiovascular and anti-inflammatory benefits, but evidence for significant skeletal muscle effects tends to emerge more consistently at this higher range and after at least 8–12 weeks of continuous supplementation (Tomczyk, 2024).

2. Should I take EPA or DHA — or both? Current evidence suggests that EPA and DHA exert distinct physiological effects and should not be treated as interchangeable. DHA appears to have a greater influence on oxygen efficiency and cardiac responses during aerobic exercise, while EPA may produce stronger anti-inflammatory effects. For most individuals, a combined EPA+DHA supplement remains the standard recommendation, but endurance athletes may benefit from a DHA-rich formulation (Blannin et al., 2025).

3. Do omega-3s help build muscle, or just prevent muscle loss? Both. The research suggests omega-3s can contribute to muscle anabolism by sensitising the mTOR signalling pathway and enhancing protein synthesis — particularly when combined with resistance training (Uchida et al., 2024). They also protect against muscle loss by reducing inflammatory-driven catabolism, which is especially important in older adults, individuals with chronic illness, or those in caloric deficit.

4. Can omega-3 supplements improve my workout performance? Possibly — particularly at submaximal intensities. Blannin et al. (2025) found that six weeks of EPA-rich or DHA-rich supplementation altered submaximal exercise physiology in trained male endurance athletes. However, the effects on peak performance, VO₂ max, or maximal strength in already well-trained individuals are less convincing from the current evidence base.

5. Are omega-3 benefits greater for older adults? Yes. The reviewed literature consistently suggests that older adults respond more favourably to omega-3 supplementation in terms of muscle-related outcomes. This is likely because aging is associated with anabolic resistance — a blunted response to normal anabolic stimuli such as amino acids and insulin — which omega-3s may partially reverse. Vascular mechanisms also appear highly relevant in this population (Karimi et al., 2025).

6. How long does it take for omega-3 supplementation to affect muscle health? Studies reporting meaningful changes in protein synthesis markers, vascular function, and muscle strength typically ran for 8–12 weeks or longer. This timeline aligns with the biological process of omega-3 incorporation into cell membrane phospholipids, which stabilises over several weeks of consistent intake. Short-term supplementation of a few days or weeks is unlikely to produce clinically meaningful muscle adaptations (Hayden & Deane, 2026).

7. Is it better to take omega-3s before or after exercise? The evidence on timing is preliminary and not definitive. Some findings reviewed by Uchida et al. (2024) suggest that pre-exercise omega-3 ingestion may optimise the anabolic window by reducing post-exercise inflammatory interference. However, the total daily dose and consistency of supplementation appear to matter far more than precise timing. Until clearer evidence emerges, prioritising consistent daily intake is more important than optimising timing.

Author’s Note

The purpose of this article is not to promote supplementation, but to clarify evidence. Omega-3 fatty acids occupy a unique space in modern nutrition science — widely consumed, heavily marketed, yet biologically complex. As a physician trained in internal medicine and metabolic health, I am particularly interested in interventions that bridge molecular physiology and real-world function. Skeletal muscle sits at the center of that intersection. It determines metabolic resilience, physical independence, recovery capacity, and long-term healthspan.

The recent shift in omega-3 research toward muscle biology reflects a broader evolution in medicine: we are moving from disease management toward functional preservation. Muscle is not merely a locomotor tissue; it is an endocrine and metabolic organ that influences glucose regulation, inflammatory tone, mitochondrial health, and aging trajectories. Understanding how EPA and DHA interact with these systems requires careful interpretation of mechanistic studies, randomized trials, and population-specific data.

Readers should also recognize that nutritional interventions rarely produce universal outcomes. Baseline dietary intake, age, training status, metabolic health, dosage, and duration all influence responsiveness. The goal of this synthesis is therefore precision — identifying where omega-3 supplementation is most likely to confer meaningful benefit and where expectations should remain modest.

Science advances through nuance, not hype. I aim to present omega-3 fatty acids not as a performance shortcut, but as a biologically plausible adjunct to resistance training, rehabilitation, and healthy aging strategies grounded in evidence rather than enthusiasm.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Individual circumstances vary, and treatment decisions should always be made in consultation with qualified healthcare professionals.

Related Articles

How Polyphenols Improve Insulin Sensitivity: The Gut-Metabolite Connection That's Revolutionizing Metabolic Health | DR T S DIDWAL

What’s New in the 2025 Blood Pressure Guidelines? A Complete Scientific Breakdown | DR T S DIDWAL

Low-Fat vs. Low-Carb: Which Diet is Best for Weight Loss? | DR T S DIDWAL

Does Saturated Fat Cause Heart Disease? What the Latest Science Really Says | DR T S DIDWAL

References

Blannin, A. B., Boulton, G., & Thielecke, F. (2025). Six weeks of either EPA-rich or DHA-rich omega-3 supplementation alters submaximal exercise physiology in endurance trained male amateurs. Frontiers in Nutrition, 12, Article 1588421. https://doi.org/10.3389/fnut.2025.1588421

Hayden, J. E., & Deane, C. S. (2026). Skeletal muscle protein turnover and mitochondrial responses to omega-3 fatty acid supplementation: An update. Current Opinion in Clinical Nutrition and Metabolic Care, 29(2), 136–140. https://doi.org/10.1097/MCO.0000000000001196

Karimi, E., Keske, M. A., Beba, M., & Kaur, G. (2025). Effects of omega-3 fatty acids on skeletal muscle vascular health and metabolism. Current Opinion in Clinical Nutrition and Metabolic Care, 28(6), 496–500. https://doi.org/10.1097/MCO.0000000000001155

Tomczyk, M. (2024). Omega-3 fatty acids and muscle strength: Current state of knowledge and future perspectives. Nutrients, 16(23), 4075. https://doi.org/10.3390/nu16234075

Uchida, Y., Tsuji, K., & Ochi, E. (2024). Effects of omega-3 fatty acids supplementation and resistance training on skeletal muscle. Clinical Nutrition ESPEN, 61, 189–196. https://doi.org/10.1016/j.clnesp.2024.03.019