Luc van Loon

At a glance

• Luc van Loon is a Dutch exercise physiologist and professor at Maastricht University (Maastricht UMC+). He is one of the world’s best-known researchers on protein, exercise and muscle mass.
• Using labelled amino acids, his team measures exactly how much protein from a meal ends up in muscle and how quickly muscle is built.
• His research showed, among other things, that protein before bed can increase overnight muscle building, and that older muscle responds less strongly to protein than young muscle.
• His group also showed how quickly muscle mass is lost during inactivity, such as bed rest or a cast: losses are measurable within days.
• He also compares animal and plant protein sources and studies how to combine them to support muscle building.
• For longevity, his work matters because maintaining muscle in later life is closely linked to independence and recovery after illness.
• Takeaway: eat a portion of protein at every meal, stay as active as possible, even while recovering, and add strength training.