Definitely do that.
Sure, glycine, other supplements and relaxation techniques that decrease brain activity are beneficial to help you unwind in the evening. However, I would focus on the bigger picture though and direct your attention towards resetting circadian rhythm and increasing sleep drive as much as possible.
Circadian rhythm and sleep drive (regulated by adenosine) are the two main systems that dictate the quality/length of your sleep as well as your daytime performance.
The mechanism behind sleep drive is the same for everyone (your adenosine levels start building up during the day and this buildup creates a chemical pressure in the evening that makes you feel sleepy) but not all people have a high sleep drive.
People with low sleep drive for example might only need 6 hours of quality sleep to feel refreshed. Trying to sleep more can inhibit their daytime cognitive and physical performances.
There are also those with medium (7 hours) and high (8+ hours) sleep drive. You going to bed by 9 PM and waking up at 3 AM (consistently?) might be an indication that you’re falling within the 6 hour low sleep drive category.
The feeling of tiredness might not only come from a lack of quality sleep due to higher cortisol levels at night but more from low cortisol levels in the morning. Cortisol and adrenaline wake you up and make you feel alert and energized to start your day in the morning.
So, what needs to be fixed here? Not your sleep drive, probably not your supplement protocol. Most likely it’s your circadian rhythm that’s misaligned with your chronotype. The question is what adjustments do you need to make to regain alignment between circadian rhythm and your chonotype?
You can play with light and body temperature to manipulate cortisol release and place the odds in your favor. Light and temperature are the two main factors that influence circadian rhythm. Off course severe psychological stress can get in the way but if that’s not an issue of yours, you can make small yet effective adaptations with those two elements.
In the morning, increase cortisol and adrenaline by exposing yourself to either bright light (5000-6000 Kelvin), or go outside for a walk. Train in the morning about an hour and a half after you wake up so your core body temperature has enough time to increase and the risk of injury goes down. Training will also boost your cortisol and adrenaline levels.
Take a cool shower if you can and have a high protein/fat breakfast afterwards to favor the uptake of tyrosine and increase cortisol and adrenaline even further. Maybe a small amount of carbs is ok but don’t go big. You want to stay focused and keep cortisol elevated at this time. Don’t worry about mTor activation, you’ll still have carbs later in the day plus amino acids themselves stimulate protein synthesis too.
If you drink coffee, have it somewhere between 8:45 and 9:15 AM if you woke up at 5:45. By noon you want to introduce carbs with protein and some fats to decrease your cortisol levels. Don’t skip lunch, eat.
Between 1 and 4 PM you will experience an afternoon slumber. Don’t drink coffee or take naps to get through it. Napping will only decrease sleep pressure and thus decrease sleep drive and coffee at this hour will make it harder to fall asleep and postpones the binding of adenosine to the adenosine receptors, increasing the risk of having some adenosine leftovers in the morning, making you feel even more tired.
Instead use lighting and be active: bright cold lights in your workspace 5000-6000 k if you can handle it or go outside and take a short walk if you can manage. Sunlight exposure and being active will recharge you by raising blood pressure, heart rate, core body temperature and cortisol levels.
Between 4 and 6 PM your cortisol levels are probably on the rise again, making you feel more alert. Use this prime time window to do your mentally challenging work. Take a small break and recharge between 6 and 7 PM.
Have dinner between 6:30 and 8:00 PM. Now you can introduce a boatload of carbs to effectively bring down cortisol and help you unwind in the evening. You can also use 3-5 g of glycine and 250 mg of magnesium (either via spray or magnesium bisglycinate) right now to further decrease brain activation.
Between 8:00 and 10:45 PM: go ahead and engage in some relaxing activities: socializing, watching tv, talking with your spouse/partner, doing some low intensity chores around the house. Take a hot shower or bath to decrease core body temperature and upregulate the production of melatonin. At 9:15 PM you completely stop blue light exposure to further increase melatonin and decrease dopamine, cortisol and adrenaline. No more mentally challenging tasks at this hour, only relaxing activities.
At 10:45 PM: lights out and go to sleep. This is a lot later than what you are used to but try to slowly build up towards that hour by working with 15 minute increases per 3-5 days.
If you can’t fall asleep after 20 minutes, try stimulus control by getting up and sitting in a chair for 15 minutes before you go to bed again. This might help lower your nightly anxiety of not being able to fall asleep and reinforces the association your brain makes between your bed and sleepy time.