I've been spending so much time outside over the last 5 weeks (I know, it's been spammed) - but the point I wanna make is that I'm certain it's why I've felt as energized as I have.
We're coming out of winter, so the strength of sunlight hasn't been the greatest, but I'm pretty sure my every-morning and nearly-every-evening walks have given me more than enough time with my face in the sun to be reaping the benefits.
In the last 2 months I've been maintaining a 1000 calorie deficit daily - and my weight loss trend has kept up with confirming this - which would usually have anyone in the PITS energy wise after 2 months. I'm not special, but maybe the reason I've only had a handful of days that have been truly testing energy wise, is because I'm spending so much time outside?
Apart from the energy, it's helped me feel so much more gratitude in my everyday life seeing what I'm surrounded by and how truly beautiful a city this place is.
Get outside more. Maybe it'll help you too.