Post-workout carbohydrates influence the importance of post-exercise recovery nutrition. This has been well described in recent years, leading to its incorporation as an integral part of training regimes in athletes and active individuals. Muscle glycogen depletion during a prolonged exercise session is one of the main factors associated with the onset of fatigue, and therefore replenishment of glycogen stores may be important for recovery of functional capacity.
Optimizing recovery in the short term is an important consideration for athletes and recreational practitioners who benefit from reduced fatigue. The notion that muscle glycogen is critical for recovery is based on a plethora of experiments demonstrating a causal relationship between muscle glycogen depletion during an initial prolonged exercise and the onset of fatigue. Thus, previous research has focused on the effects on different nutritional interventions to increase the availability of this substrate, although the amount/composition of nutrients remains debatable.
Research points out that the ability to recover after exercise is influenced by carbohydrate intake, which is consistent with the role of carbohydrate supplementation in an initial prolonged exercise session. A dose-dependent relationship between carbohydrate intake during short-term recovery and restoration of resilience may be present, but more research is needed regarding the precise dose, type, and/or frequency of carbohydrate feeding during limited recovery to optimize repeated exercise capacity.
Glucose and glycogen
Glucose is the precursor of glycogen resynthesis and it is consequently understandable why the amount of glucose ingested is such an important determinant of the rate of glycogen resynthesis. In the context of recovery from exhaustive exercise, it is known that the intake of 6 to 12 g of carbohydrates per kilogram of weight is sufficient to restore endogenous glycogen reserves when the recovery time is longer than 24 hours. However, athletes and individuals active in a wide range of sports train and compete at levels that challenge their daily glycogen stores with minimal time to recovery. Thus, when the time available for recovery is limited (<8 h), neither muscle glycogen nor subsequent exercise capacity can be fully restored.
Co-protein intake can accelerate muscle glycogen content relative to carbohydrate alone. This is especially true when the protein and carbohydrate solution provides more calories than a carbohydrate-only solution and/or when carbohydrate intake during the short term. It becomes apparent that specific nutritional strategies aimed at acutely accelerating glycogen resynthesis are important considerations in such scenarios. The ideal carbohydrate feeding strategy for maximizing glycogen stores varies greatly and depends on several factors that include, the amount, time, and type of carbohydrates ingested during recovery.
Post-workout carbohydrate intake can be used to influence the restoration of endurance capacity after exhaustive exercise. Thus, when the goal is to optimize repeated exercise capacity after short-term recovery, ingesting carbohydrates in an amount ≥1.2 g kg of body mass can maximize muscle glycogen replacement.
Adding carbohydrate protein during post-exercise recovery may be beneficial in circumstances when carbohydrate intake is suboptimal (≤0.8 g kg of body mass) for effective glycogen restoration and repeated exercise capacity.
Effect of carbohydrates on bodybuilding
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– Alghannam AF, Gonzalez JT, Betts JA. Restoration of Muscle Glycogen and Functional Capacity: Role of Post-Exercise Carbohydrate and Protein Co-Ingestion. Nutrients. 2018;10(2):253. Published 2018 Feb 23. doi:10.3390/nu10020253