Best time for 2nd serving of Glutamine?

i always take 10 g of glutamine everyday. My first 5 g serving is right b4 morning cardio and currently my sencond serving has been just b4 weight training at night. When is the best time for the 2nd serving i know that its bad right after training but when is it good?

before bed or before weight training. I prefer before bed because it helps in muscle repair while your sleeping.