So I have been kinda primal for some time, rather due to gluten intolerance and casein alergy. Loved my bread and choc shakes. Anyway, does anyone go through the same feeling when starting cardio work - even after a very light session of walking, swimming or simple garden work (could do all those things no problem 3 yrs ago at age 44), I am wasted. Not huffing and puffing but I really feel lousy, weak and shaky and no enrgy or desire to do it again. This after about 15 min of work at a heart rate of 50 to 55% max. I have never been a fitness person, rather a sports person - now I want to get into shape to do the sports again. I have been slack and sedentary for many years. 6,1 180lbs flabby.
You just need to start walking. And walk a lot. Once you can walk alot (like 30 minutes every day) then you need to start doing some body weight exercise. Highly recommend the Primal workout - love it.
I've been working out so long that I don't have the issues you describe but your body was made to move, so just move slowly and a lot.
I'm by no means an expert, so don't take my advice as so... but I do have some experience with those symptoms.
First, I totally agree with profdjj - start EASY. I always hated exercise because my experience with it was running the mile in school, etc. In all my sports/exercise experience when I was young, I never "trained" I was just thrown into it and expected to be able to do it, like with the mile. After college, I was coerced by a friend into a running program (I really started it for her, and ended up loving it for me). The key was I started sloooow... the couch to 5k program. Building up to exercise makes it so much easier in the end. If you try to go head first into it, you get exhausted and can never recover. Try googling "overtraining" and see if the symptoms are what you are experiencing. Even with walking - try walking slow for 10 minutes a couple of times a day, as opposed to trying to do it all at once. Baby steps are key, and getting into a fitness regime after being sedentary for a while is not easy. Just try to get over the first month or so - I promise it does get easier!
If you do think you are starting off slow, and still having the same symptoms, maybe you need to introduce some more "starchy" carbs. Not grains, but things like sweet potatoes, butternut squash, fruit, etc. Some people just need that energy, especially during a transition time until your body figures out how to keep its energy up.
Hope that helps some!
It could also be worn out adrenals or a thyroid issue. Gluten intolerance really messes with those systems. I had to start taking Armour and some adrenal herbs (prescribed by a doctor). Maybe listen to your body and rest more!