Nutrient timing strategies for peak athletic performance
By Kelly C. Heim, Ph.D.
Consistent training and sound nutrition are the time-honored pillars of physical fitness.While supplemental amino acids, creatine and carbohydrate are well-known to support fueling and recovery, research suggests that the timing of their ingestion is highly relevant to maximizing gains.In recent years, numerous studies have also indicated that the success of adaptive responses to training and recovery can be potentiated to a greater extent through temporal coordination of nutrient supplementation versus unscheduled intake. 1-3
The sensitivity of muscle to carbohydrate, amino acids and creatine is greatest during the first 30 minutes of the recovery period. A second window of opportunity exists between 1-3 hours post-exercise, in which protein synthesis can be maximally supported by a combination of high-quality protein and carbohydrate in a 1:3 or 1:4 ratio (protein: carbohydrate).3,4 While simple carbohydrates are ideal during the initial recovery period, a low-glycemic diet after this period will support a steady availability of glucose and amino acids for glycogen repletion, protein synthesis and strength gains.
Glucose and maltodextrin
During prolonged exercise exceeding 1 hour, a glucose or maltodextrin beverage taken every 10-30 minutes supports a favorable cortisol balance and spares glycogen to promote endurance and post-exercise recovery.3 A 6-8% carbohydrate beverage with electrolytes is a highly versatile pre- and post-workout hydration option into which BCAA and/or creatine can be mixed for convenience.
Protein and amino acids
Amino acid uptake into muscle increases during and immediately following exercise due to increased blood flow and sensitization of transport systems.Accordingly, protein or amino acids taken 30 minutes prior to a workout promotes protein retention during and after activity.3 Branched chain amino acids (BCAA) consumed with l-arginine before exercise have been shown to maintain muscle protein balance during a workout.5 Combining protein with simple carbohydrates promotes post-exercise recovery. 3,6Whey protein isolate is ideally suited for post-workout recovery as it is quickly digested and rapidly increases plasma levels of BCAA, particularly leucine, a key regulator of protein synthesis.6
Pre- and post-exercise creatine supplementation elevates intramuscular creatine to a greater extent than intake unassociated with a workout.1,2Adding arginine alpha-ketoglutarate to support healthy blood flow or a glucose/maltodextrin beverage can further potentiate muscular uptake.3,7
Regardless of an individual’s fitness goals, supplement timing presents an evidence-based method of optimal fueling and recovery.This emerging area of sports nutrition is broadly applicable to endurance and resistance training programs for any athlete in pursuit of peak performance.
- Cribb PJ, Hayes A. Effects of supplement timing and resistance exercise on skeletal muscle hypertrophy. Med Sci Sports Exerc. 2006 Nov;38(11):1918-25.
- Candow DG, Chilibeck PD.Timing of creatine or protein supplementation and resistance training in the elderly. Appl Physiol Nutr Metab. 2008 Feb;33(1):184-90.
- Kerksick C, Harvey T, Stout J, Campbell B, Wilborn C, Kreider R, Kalman D, Ziegenfuss T, Lopez H, Landis J, Ivy JL, Antonio J. International Society of Sports Nutrition position stand: nutrient timing.J Int Soc Sports Nutr. 2008 Oct 3;5:17.
- Volek JS. Influence of nutrition on responses to resistance training. Med Sci Sports Exerc. 2004 Apr;36(4):689-96.
- Matsumoto K, Mizuno M, Mizuno T, Dilling-Hansen B, Lahoz A, Bertelsen V, Münster H, Jordening H, Hamada K, Doi T. Branched-chain amino acids and arginine supplementation attenuates skeletal muscle proteolysis induced by moderate exercise in young individuals. Int J Sports Med. 2007 Jun;28(6):531-8.
- Farnfield MM, Trenerry C, Carey KA, Cameron-Smith D.Plasma amino acid response after ingestion of different whey protein fractions. Int J Food Sci Nutr. 2008 May 8:1-11.
- Little JP, Forbes SC, Candow DG, Cornish SM, Chilibeck PD. Creatine, arginine alpha-ketoglutarate, amino acids, and medium-chain triglycerides and endurance and performance.Int J Sport Nutr Exerc Metab. 2008 Oct;18(5):493-508.