2 brew in advance and carry it with you. Protein powder is inconvenient to carry. At this time, I suggest you brew at home and take it to the gym. You can drink it directly after training. It is the most timely, but the water temperature is not high and it is not suitable for winter.
It is the easiest way to go to the gym after drinking protein powder, which completely omits the operation of "taking", which meets the requirements of supplementing protein before fitness, but it will be insufficient after training.
It is recommended to go home to drink after training. The so-called prime time for replenishment is just a marketing tool for merchants. It's no problem to make it up at home after training, as long as it is made up within 12 hours.