Macronutrient Balance: Nutritional Guide for Athletes

Macronutrients — proteins, carbohydrates and fats — are the three fundamental pillars of any nutrition strategy for strength training. Understanding their role, knowing how to portion them and adapting them to your goal is essential for making progress, recovering effectively and optimizing your body composition, whether you are in a muscle gain phase, cutting phase or recomposition phase.

However, many athletes neglect this balance by focusing solely on protein, fearing carbohydrates or demonizing fats. In this Force Addict Pro guide, you will discover the specific role of each macronutrient, how to calculate your needs according to your goal, and how to build a consistent, sustainable diet to support your performance.

What is a macronutrient?

Macronutrients are nutrients that the body uses in large amounts to produce energy, build tissues and ensure the body functions properly. In sports nutrition, the three macronutrients are proteins (4 kcal/g), carbohydrates (4 kcal/g) and fats (9 kcal/g). None should be eliminated — even fats, which are often misunderstood, are essential for proper hormonal and joint function.

• proteins: muscle building and repair;
• carbohydrates: the main fuel for intense exercise;
• fats: energy, hormones and absorption of fat-soluble vitamins;
• the balance varies according to the athlete's goal and profile.

Proteins: the pillar of muscle building

How much protein does an athlete need?

Jäger et al. (2017, Journal of the International Society of Sports Nutrition) recommend an intake of 1.4 to 2.0 g of protein per kilogram of body weight per day for most individuals, divided into doses of 20 to 40 g every 3 to 4 hours. Morton et al. (2018, British Journal of Sports Medicine), in a meta-analysis of 49 studies and 1863 participants, confirm that a threshold of 1.6 g/kg/day maximizes lean mass gains associated with resistance training, beyond which additional intake provides no significant benefit for most individuals.

Best protein sources

The best food sources include eggs, chicken, turkey, lean beef, fish, cottage cheese and skyr. As a supplement, whey protein or micellar casein can help you easily meet your daily intake.

Carbohydrates: fuel for performance

Carbohydrates are the body's preferred source of energy during intense exercise. Burke et al. (2011, Journal of Sports Sciences) recommend an intake of 30 to 60 g of carbohydrates per hour of exercise for prolonged sessions, which can rise to 90 g/hour for efforts lasting more than 2.5 hours with mixtures of different carbohydrate types. Drastically reducing carbohydrates without a specific reason can impair performance and training quality.

Simple vs. complex carbohydrates

Complex carbohydrates (oats, brown rice, potatoes, legumes) release energy gradually and form the basis of an athlete's meals. Simple carbohydrates (fruit, dextrose, maltodextrin) can be useful around training. To learn more, see our guide to energy foods for athletes.

How many carbohydrates should you consume?

During a muscle gain phase, an intake of 4 to 6 g/kg/day is common. During a cutting phase, intake can drop to 2 to 3 g/kg/day depending on tolerance and workout intensity.

Fats: essential for hormones and health

Fats play a fundamental and often underestimated role: hormone production, absorption of vitamins A, D, E and K, joint lubrication and cardiovascular health. A diet that is too low in fats can disrupt hormonal balance and weaken the joints.

Good fats vs. bad fats

Monounsaturated and polyunsaturated fatty acids (olive oil, avocados, nuts and seeds, fatty fish, omega-3s) should be prioritized. Industrial trans fatty acids should be avoided.

How much fat should you consume?

An intake of 0.8 to 1.5 g of fat per kilogram of body weight per day is a common range for athletes. Helms et al. (2014, Journal of the International Society of Sports Nutrition), in their review of natural bodybuilding preparation, recommend maintaining 15 to 30 % of total calories from fats, even during periods of calorie restriction, to preserve hormonal health.

Calculating your macronutrients according to your goal

Macronutrients during a muscle gain phase

During a muscle gain phase, the goal is to create a controlled calorie surplus (200 to 400 kcal/day above maintenance). To increase calorie intake without multiplying meals, a gainer can be useful. See our guide: which gainer to choose.

Macronutrients during a muscle cutting phase

During a cutting phase, the calorie deficit should be gradual (300 to 500 kcal/day below maintenance), in line with the rate of 0.5 to 1 % of body weight per week recommended by Helms et al. to preserve muscle mass. Increasing protein intake helps limit catabolism.

Macronutrients during body recomposition

Body recomposition involves losing fat while gaining or maintaining muscle simultaneously. A high protein intake, careful calorie management around maintenance and structured resistance training are the three essential levers.

Common mistakes in macronutrient management

• eliminating carbohydrates without calculating the impact on performance;
• underestimating fat intake and disrupting hormonal balance;
• setting protein intake too high without adjusting other macros;
• not adapting macros to training and rest days;
• neglecting the quality of food sources in favor of counting alone.

Recommended products and collections

• Strength Training Proteins: complete collection of whey, casein and protein supplements.
• Whey Isolate: a lighter protein, ideal during a cutting phase.
• Gainers: high-calorie supplement for muscle gain.
• Micellar Casein: slow-release protein, ideal before bedtime.

Go further in your progress

• Complete guide to proteins for strength training
• Energy foods for athletes
• How to gain muscle mass naturally
• Which gainer should you choose: lean, hard or classic?

Scientific references

• Morton RW, Murphy KT, McKellar SR, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018;52(6):376–384. doi:10.1136/bjsports-2017-097608
• Jäger R, Kerksick CM, Campbell BI, et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20. doi:10.1186/s12970-017-0177-8
• Burke LM, Hawley JA, Wong SHS, Jeukendrup AE. Carbohydrates for training and competition. J Sports Sci. 2011;29(Suppl 1):S17–S27. doi:10.1080/02640414.2011.585473
• Helms ER, Aragon AA, Fitschen PJ. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. J Int Soc Sports Nutr. 2014;11:20. doi:10.1186/1550-2783-11-20

Key takeaways

Macronutrient balance is one of the most powerful levers for optimizing performance, body composition and recovery in strength training. Proteins build and repair muscle (1.4 to 2.0 g/kg/day according to the ISSN), carbohydrates fuel intense training (30 to 60 g/hour of exercise according to Burke et al.) and fats support hormones and overall health (15 to 30 % of calories according to Helms et al.). No macronutrient should be eliminated — only their ratio changes according to the goal.

To make lasting progress, calculate your needs based on your weight, goal and activity level, then adjust gradually by monitoring your body composition week after week. This is the rational, data-driven approach that Force Addict Pro promotes through its guides and selection of supplements suited to every training phase.