I have come for some advice on how to get some energy back, the past few months I have been doing a lot of sitting and by alot I mean TUNS nearly all day long. I have noticed now when standing I have to sit back down pretty fast. I have no energy to clean or to spend with my children lately. I am like a lump of rocks. I have been spending nearly all day long working from my computer, other than making dinners and what not. I am ultra tired all the time and extremely weak.
I have also noticed I get knee pain and a popping feeling in my right knee since I have been sitting so often. I never had knee problems before and I have not done anything to cause something to rip ot break only sitting too long.
Energy? Hmm... I too sit on the job, hours per day at a computer. What I have done is set up a step block by the desk and I stop work every hour (or less) for a minute and step up and down while I think about a work topic or just to take a break. It gets my blood flowing, is good for my legs (including knees of course) and gets me out of the chair for a bit. And it is energizing.
BUT, if every time I stood up I felt horrid, I would not do steps! Maybe you are feeling carb flu? I did a couple of times over the last 8 months since I began paleo. I felt how you describe, minus the crackling knees.
Before work each morning, I have bullet-proof coffee (coffee with or without cream and 1 tablespoon coconut oil) and since I started it seems to have boosted my energy level higher than usual and I have no hunger for several hours after.
This sounds more like an activity rather than diet problem. Getting into the habit of talking a walk (outside preferably) for 5 minutes every hour or two at work can make a big difference, but it is difficult when you don't feel like you have the energy and your options for being active are limited. Any exercise you can do though pretty much always seems to pay off.
Is getting a standing desk an option? I know when I is for a long period of time my energy is crap. You coul also do some squats, pushups, jumping jacks, every hour for like 3-5 minutes to keep the blood flowing. As far as food goes, kombuscha always give me a pick me up after a long sitting day.