Dedicated gymgoers keep a tub (or even two) of protein powder front and center on their kitchen counters at all times.

Creatinine synthesis is age-dependent. As measured by urinary excretion, it decreases with increasing age, falling from a mean 23.8 mg/kg body weight in men aged 20 to 29 years to 9.8 mg/kg body ...

Medically reviewed by Mary Choy, PharmD Creatine is a nonessential amino acid produced in the body from other amino acids. It is found mostly in muscles, including the heart, and in small amounts ...

High muscle mass Because creatinine results from creatine breakdown during muscle synthesis, people with more muscle mass will naturally have higher creatinine levels in their blood, Zuquello says.

These support creatine synthesis and muscle recovery. A 2-tablespoon serving packs around 5g of protein and a good dose of fiber and healthy fats, ...