Creatine O'Clock: Does Timing of Ingestion Really Influence Muscle Mass and Performance?

Abstract

It is well-established that creatine supplementation augments the gains in muscle mass and performance during periods of resistance training. However, whether the timing of creatine ingestion influences these physical and physiological adaptations is unclear. Muscle contractions increase blood flow and possibly creatine transport kinetics which has led some to speculate that creatine in close proximity to resistance training sessions may lead to superior improvements in muscle mass and performance. Furthermore, creatine co-ingested with carbohydrates or a mixture of carbohydrates and protein that alter insulin enhance creatine uptake. The purpose of this narrative review is to (i) discuss the purported mechanisms and variables that possibly justify creatine timing strategies, (ii) to critically evaluate research examining the strategic ingestion of creatine during a resistance training program, and (iii) provide future research directions pertaining to creatine timing.

Keywords: blood flow; creatine kinetics; muscle; resistance training; strength.

Figure 1

Exercise induced muscle hyperaemia paired with creatine absorption may alter creatine uptake and retention. Creatine peaks <2 h after ingestion and remains elevated for ~4 h, while blood flow may return to baseline within 30 min after exercise. Based on this mechanisms, creatine before exercise may be ideal. Exercise modulates Na⁺-K⁻ pump activity, therefore pairing creative absorption with maximal pump activity may enhance creatine uptake. However, Na⁺-K⁺ activity is upregulated for much longer, therefore re tine in close proximity to exercise (either before or after) may be ideal compared to other time of the day. Creatine kinetics are modified by co-ingestion with carbohydrates alone or carbohydrates and protein. Therefore, timing of creatine may be partially dependent on the co-ingestion with marconutrients. Created with BioRender.com.