Being able to benefit from high-quality nutrients during training can bring significant improvements in performance. Without intermediate supplementation, the body quickly breaks down amino acids, glycogen and basic electrolytes. This not only reduces strength and performance in training but completely destroys muscle gains due to the degradation of valuable muscle tissue.
A situation like this should not happen to any athlete or any serious active person and supplements during physical training are important for quick muscle recovery and development and for increasing the duration and volume of your training as your body will never run out of available fuel. If you are the type of athlete that doesn't compromise and requires the best improvements in the future, then using an intra-workout product is your most appropriate option.