Muscle hypertrophy

Hypertrophy is muscle growth through an increase in the volume of existing fibres (not in their number). It results from a positive balance between muscle protein synthesis and breakdown, triggered by the mechanical load of training.

The three drivers of hypertrophy:

1. Mechanical tension: lifting sufficiently heavy loads (the main stimulus)
2. Metabolic stress: the “burn” of long sets
3. Muscle damage: micro-tears that are repaired stronger

An original angle (nutrition and timing):

• Protein: about 1.6 to 2.2 g/kg/day is enough to maximise hypertrophy. Beyond that there is no extra benefit (despite marketing that pushes you to overconsume)
• Distribution: about 20 to 40 g of protein per meal, spread over the day, is better than a single massive dose. Each meal “restarts” synthesis
• Moderate calorie surplus: building muscle takes energy (a slight surplus of about 10 to 20% is optimal)
• Leucine: the “trigger” amino acid for synthesis (about 2.5 to 3 g per meal)

Myth-busting:

• You CANNOT turn fat into muscle (they are two distinct tissues)
• The 30-minute “anabolic window” is an overrated myth (see the entry)
• Women do not easily “bulk up” (little testosterone): they tone up
• Muscle is built during recovery (rest + sleep), not during the workout itself

The most underrated factor is sleep. One bad night reduces protein synthesis and raises catabolic cortisol. Sleeping is as important as training and eating.