To Grow, Carbs are necessary. When, How much and what type of carbs matters significantly. During Training they act as an immediate fuel source, to help improve performance, help in faster recovery and keep harmful hormones like cortisol down and all the beneficial hormones up.
Very Important for people who want to gain size and for highly active people, who need more calories to increase in size. Carbs after training helps spike insulin levels to kick muscle growth into overdrive. It doesn’t happen directly, but indirectly it helps in muscle growth as it pushes amino acids & glucose into muscle cells and has an anti-catabolic properties. It also prevents leaking out of nutrients from the cells which usually occurs because of training.
The rate of glycogen resynthesis is the highest for the first 30 mins and then it significantly decreased by 60%, through the remaining 4.5 hours of recovery. So feed yourself with the fastest absorbing carbs.