Hey there!
I might be a bit off-road here, from your title. But I can give you my personal experience on smoothies and training.
When I tapered off Valium one time ( I have done it many times though, but it might be an interesting advice ), I pushed myself to take long walks, workout hard, and make green smothies. I didn`t actually have a recipy, but normal ingredients in one smoothie for me could be: 1 carrot, some peanuts ( DO NOT USE if you are allergic ), Chia-seeds, spinach, Oak-meal, sunflower-seeds, One spoon of proteinpowder, maybe some berries, combined with a mix of non fat-milk and WATER ( always drink much water, it`s like 80 % uf us ). I know this may sound weird, but I also took a tablespoon of sunflower-oil or Olive-oil as a shot too, and omega 3.
I think this pretty much covered all the needs I had, and I felt very energized, and became very strong and fit.
Cleansing food is often lemon, ginger, water.
If you have like a stomach that is in a bad mood, for example the way you feel if you drink too much coffee on an empty stomach etc, I find natural yougurt to be very helpful. With natural flavor, that is. Or some of the yoghurt-drinks that I don`t know how to say in english.
But please note that I am not a doctor, and if you have any allergies or intolerances, please be aware that I am only talking "mainstream"-health here.
And yeah, if you drink alot of coffee: Don`t.
I hope this helped a bit.