The pre-workout lexicon

One-Rep Max: the heaviest load you can lift once. It can be estimated with the Brzycki/Epley formulas, without attempting a true maximal lift. Work out your 1RM.

The building block of proteins. The body uses 20 of them, 9 of which are essential (they have to come from food). BCAAs and EAAs are amino acid supplements.

An enzyme that regulates energy metabolism. Activated during effort, it drives fat burning and autophagy.

The tissue-building (muscle-building) phase. The opposite of catabolism. Supported by protein intake + resistance training.

Adenosine triphosphate. The "energy currency" of cells. Creatine regenerates ATP, increasing your power on efforts < 10s.

Branched-Chain Amino Acids: leucine, isoleucine, valine. Classic ratio 2:1:1. Useful if your protein intake is too low, otherwise redundant.

A precursor of muscle carnosine. A pH buffer that pushes acidosis back and improves muscular endurance on efforts of 30s-10min. Cumulative effects over 4-8 weeks. → our article

An extracellular buffer. Fights metabolic acidosis on efforts of 1-7min (middle-distance running, Hyrox transitions). To be taken 60-90 min before the effort.

Basal Metabolic Rate: the minimum energy needed for vital functions at rest. Calculated with Mifflin-St Jeor from age, sex, weight and height.

The most studied stimulant in the world. An adenosine receptor antagonist. Presented on a strictly factual basis — no health claim is authorised for caffeine (dose 0-200 mg/portion, ANSES ceiling). → our article

A muscle dipeptide that acts as a pH buffer. Synthesised from beta-alanine. The more you have, the further you push the lactic wall back.

The tissue-breakdown phase (muscle loss). The opposite of anabolism. Encouraged by a severe calorie deficit + a lack of protein.

A precursor of arginine and nitric oxide (NO). Increases blood flow to the muscle (the "pump" effect) and supports perceived muscle recovery (Pérez-Guisado 2010 study on 41 trained subjects). → our article

The most studied active in sports nutrition. Regenerates ATP through creatine kinase and supplies immediate energy for explosive efforts (1-10s). Authorised EFSA claim Reg 432/2012: increases physical performance in successive bursts of short-term, high-intensity exercise (≥ 3g/day). → our article

Delayed Onset Muscle Soreness. Peaks 24-72h after eccentric work. Not a sign of progress, just a sign of unusual muscular stress.

An osmolyte: it draws water into tissues and holds it there. Studied in endurance athletes for hyperhydration before a long effort or in high heat. No authorised health claim — presented on a strictly factual basis.

The storage form of carbohydrate in muscle and liver. The main fuel for intense efforts. Restored 24-48h after the effort with carbohydrate intake.

High-Intensity Interval Training. Alternating intense efforts and short recoveries. Improves VO2 max and burns fat after the session (afterburn).

An increase in muscle volume. Optimised by sets of 8-12 reps at 70-80% of 1RM, under prolonged tension, with a protein intake of 1.6-2.2g/kg.

An amino acid found almost exclusively in tea (Camellia sinensis). Often studied alongside caffeine on attention tasks. No health claim is authorised in Europe — presented on a strictly factual basis.

An amino acid, a precursor of dopamine, noradrenaline and adrenaline. Critical under stress (competition, hard training). Excellent synergy with caffeine.

The most important BCAA for protein synthesis. The main trigger of the mTOR pathway. 2.5-3g per meal optimises muscle growth.

Macronutrients: protein (4 kcal/g), carbohydrate (4 kcal/g), fat (9 kcal/g). The optimal split depends on your goal.

The daily calorie intake that keeps your weight stable. Calculated as TDEE = BMR × activity level.

Mechanistic Target of Rapamycin. The cellular signalling pathway that triggers protein synthesis. Activated by leucine + resistance work.

Non-Exercise Activity Thermogenesis. Calories burned outside exercise (walking, fidgeting, posture). Accounts for up to 50% of energy expenditure.

A vasodilator molecule. Increases blood flow to the muscle. Boosted by citrulline, arginine and beetroot (nitrates).

Organising training in cycles (volume, intensity, frequency) to optimise progress and avoid overtraining. Cycles of 4-8 weeks.

The storage form of immediate energy (efforts <10s). Regenerates ATP. Increased by creatine supplementation.

The alkaloid that gives black pepper its bite. Studied for its influence on the bioavailability of certain nutrients. Used in microdoses — a few milligrams are enough. No authorised health claim — presented on a strictly factual basis.

A macronutrient essential to building muscle. Athlete requirement: 1.6 to 2.2g per kg of body weight. Sources: meat, fish, eggs, whey, pulses.

Rate of Perceived Exertion (1-10 scale). A subjective rating of how hard a set was. RPE 8 = "I could have done 2 more reps".

A rock salt known as "Himalayan", essentially sodium chloride — its colour comes from trace minerals, including iron. Sodium is the main electrolyte lost in sweat: how much you take depends on the length of the effort and the heat.

The post-effort adaptation in which performance goes beyond the starting level. It needs enough recovery (48-72h per muscle group).

The cellular process of building muscle from amino acids. Stimulated for 24-48h after training, with an optimal window of 0-3h.

A sulphur-containing amino acid, abundant in muscle and in the heart, which the body can synthesise itself. One of the most studied molecules in exercise physiology. No health claim is authorised in Europe — presented on a strictly factual basis.

Total Daily Energy Expenditure. The total calories burned in a day. = BMR × activity level (1.2 sedentary to 1.9 highly active).

Training volume = sets × reps × load. The main lever for hypertrophy. Optimum: 10-20 sets per muscle group per week.

The maximum capacity to use oxygen (mL/kg/min). A key indicator of endurance. Can be improved by 15-25% in 3-6 months of HIIT training.

Whey protein, fast digesting. Whey concentrate (~80% protein), whey isolate (~90%, lactose-free). Ideal post-workout.

Mineral salts (sodium, potassium, magnesium) essential to cellular hydration and muscle contraction. Critical on efforts > 1h or in the heat.