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Fueling your flex: Essential nutrients for muscle health


Hitting that flex goal is all about fuelling your body right to help your muscles grow and repair. And while that may have you reaching for the nearest protein-packed snack, optimizing muscle function, growth, and maintenance isn’t only about protein. It's true - we're about to discover what foods fuel your flex.

Macronutrients for muscle health

Macronutrients are the “big three” building blocks of nutrition that your body requires for energy and upkeep of your body’s fundamental structures. The “big three” are composed of the following:  carbohydrates, proteins and fats. Each of these is important for muscle growth and recovery.

And while protein gets all the hype in the health and fitness industry – it’s a myth that only protein is required to build muscle. In fact, research shows that bodybuilders, who are judged solely on their muscular appearance rather than their physical performance, need 55 to 60% carbs, 25-30% protein, and 15-20% fat during their off-season or pre-contest phases.1

But how exactly do the other macronutrients fuel your gains? Let's uncover their muscle-building might.

Carbohydrates for muscle function and repair

Complex carbs fuel muscle contractions, helping you to power through movement and sustain exercise.

When you consume complex carbs, they are broken down into simple sugars that can be used for immediate energy, and any excess can be stored as glycogen in the muscles for future use.

Replenishing your muscle glycogen stores is also important for muscle repair. Endurance athletes should consider consuming 1.2 g of carbs per kilogram of body mass per hour for the first few hours of recovery.2

Healthy carbohydrate sources:

  • Green leafy vegetables: asparagus, broccoli, kale
  • Vegetables: aubergines, carrots, squash
  • Wholegrains: brown rice, oatmeal, quinoa

Protein for muscle gain

While protein is not the end-all-be-all, there’s no denying that it is paramount if you’re looking to increase your muscle mass. The American College of Sports Medicine recommends that anyone regularly lifting weights or training for endurance events should eat 1.2 - 1.7 g of protein per kg of body weight each day.3

Healthy protein food sources:

  • Eggs
  • Lean meat
  • Chicken breast
  • Edamame

Fats for lean muscles

For those aiming to bulk up with lean muscle, upping your omega-3 fatty acids, found abundantly in salmon, mackerel, and sardines, is key.4 Fats are also important for kick-starting the muscle recovery process following exercise.

Healthy muscle-building fats:

  • Avocados
  • Oily fish
  • Nuts

Water: The forgotten macronutrient

Water, often overlooked, is crucial for delivering the essential nutrients and materials vital for muscle growth. Your muscles are over three-quarters water (76%) after all.5 Research shows that during times of dehydration, muscles are the first to lose water, alongside the skin, which can affect their mechanical and metabolic functions. Without adequate water, your muscles cannot function or repair themselves properly.



It's not just about macros for muscle health; micronutrients play a pivotal role in supporting muscle recovery, maintenance, and output.


Iron is an important component of myoglobin, a protein that stores oxygen in your muscle tissues. A lack of dietary iron could reduce muscle myoglobin and reduce the oxidative capacity of your muscles.6

Iron is present in:

  • Liver
  • Red meat
  • Spinach


Calcium is found in dairy products, like milk, yogurt, and cheese, and is vital for muscle contraction. Without enough calcium in your diet, you may find you experience muscle cramps and fatigue.

Vitamin D

You may be familiar with the role of vitamin D for bone health, but the sunshine vitamin is also known to support muscle repair and contraction. Vitamin D deficiency can reduce calcium reuptake by muscle cells which can affect contraction.7

Research also shows that vitamin D supplementation can help with muscle recovery by attenuating damage and inflammation following exercise.8

Vitamin D is available in a few foods, including eggs and mushrooms, but most of it comes from sunlight exposure.


Electrolytes such as calcium, magnesium, potassium, and sodium are vital for normal muscle contraction and to keep fatigue at bay.


Creatine is important for the production of adenosine triphosphate (ATP), the body’s basic form of energy. Creatine supplementation increases your stores of phosphocreatine which is essential for the production of new ATP during exercise. In other words, understanding energy systems can help sustain muscle function during intense exercise. Get the lowdown on energy systems in our Beginner's Guide article.

And if you’re looking to naturally increase your creatine intake, try eating pork, chicken, beef, and cod.


Some sources claim that zinc can improve muscle strength and performance through its potential involvement in the synthesis and regeneration of skeletal muscle following exercise.9  Rich sources of zinc include meat, fish, and seafood, especially oysters.


Healthy meal ideas to promote muscle health

To supercharge your muscle gains, why not test out these powerhouse meals? Packed with muscle-building ingredients, they'll fuel your gains and accelerate recovery.

  1. Grilled salmon with a quinoa salad and steamed tender stem broccoli and asparagus
  2. Sirloin steak, sweet potato wedges, and a spinach side salad
  3. Chickpea and spinach curry with brown rice

Let’s recap

Building and maintaining healthy muscles requires more than just whey protein shakes and grilled chicken. Carbs, fats, iron, calcium, electrolytes, vitamin D, creatine, and zinc are all crucial players in fueling muscle growth, function, and recovery. And don’t skimp on that H20 to keep your muscles hydrated and ready for action.

At the end of the day, it’s all about striking that balance of nutrients to fuel your muscles and help you crush your goals – because that’s the ultimate flex.

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[1] Lambert, C. P., Frank, L. L., & Evans, W. J. (2004). Macronutrient considerations for the sport of bodybuilding. Sports medicine (Auckland, N.Z.), 34(5), 317–327.

[2] Gonzalez, J. T., & Wallis, G. A. (2021). Carb-conscious: the role of carbohydrate intake in recovery from exercise. Current opinion in clinical nutrition and metabolic care, 24(4), 364–371.

[3] Protein intake for optimal muscle maintenance (no date) ACSM. Available at: (Accessed: 17 April 2024).

[4] McGlory, C., Calder, P. C., & Nunes, E. A. (2019). The Influence of Omega-3 Fatty Acids on Skeletal Muscle Protein Turnover in Health, Disuse, and Disease. Frontiers in nutrition, 6, 144.

[5] Lorenzo, I., Serra-Prat, M., & Yébenes, J. C. (2019). The Role of Water Homeostasis in Muscle Function and Frailty: A Review. Nutrients, 11(8), 1857.

[6] Hagler, L., Askew, E. W., Neville, J. R., Mellick, P. W., Coppes, R. I., Jr, & Lowder, J. F., Jr (1981). Influence of dietary iron deficiency on hemoglobin, myoglobin, their respective reductases, and skeletal muscle mitochondrial respiration. The American journal of clinical nutrition, 34(10), 2169–2177.

[7] Latham, C.M. et al. (2021) ‘Vitamin D promotes skeletal muscle regeneration and mitochondrial health’, Frontiers in Physiology, 12. doi:10.3389/fphys.2021.660498.

[8] Rojano‐Ortega, D. and Berral‐de la Rosa, F.J. (2022) ‘Effects of vitamin D supplementation on Muscle Function and recovery after exercise‐induced muscle damage: A systematic review’, Journal of Human Nutrition and Dietetics, 36(3), pp. 1068–1078. doi:10.1111/jhn.13084.

[9] Hernández-Camacho, J. D., Vicente-García, C., Parsons, D. S., & Navas-Enamorado, I. (2020). Zinc at the crossroads of exercise and proteostasis. Redox biology, 35, 101529.