Taking 3 grams of glycine before bed doesn't make people feel sleepy during the day.

Taking 3 grams of glycine before bed doesn't change how much time people spend in different sleep stages (light sleep, deep sleep, REM sleep).

Taking 3 grams of glycine before bed makes people feel less sleepy at 10 AM the next day.

Taking 3 grams of glycine before bed helps people spend more time actually sleeping while in bed, rather than lying awake.

Taking 3 grams of glycine before bed makes people who have trouble sleeping feel more satisfied with their sleep.

Taking 3 grams of glycine before bed helps people fall asleep faster, as measured by sleep monitoring equipment.