PreSeries STIM-FREE is a pre-workout made by Transparent Labs. It was developed to boost endurance and focus without stimulant effects.
The pre-workout features 11 ingredients. The Transparent Labs website refers to citrulline malate as “the star child of pre-workout science”. It is included to increase nitric oxide and improve “strength”, “muscle endurance” and “aerobic performance”. L-norvaline is said to work alongside L-citrulline malate to produce nitric oxide.
The brand also says it includes beta-alanine to “promote the formation of healthy proteins” and to reduce “neuromuscular fatigue”.
Meanwhile, L-tyrosine could reduce stress, improve focus and boost endurance.