The third component of Paleo is emulating the day time hours. We assume he spent most of his time between finding food and creating living spaces. He did not go to the gym or spend time running around an oval track, swimming laps, or cycling in competitions.
I confess I do have a gym membership but only because it is really cheap and comes with my current employment. But I never have time to go with any regularity and I find most of the activities boring. But there is the social aspect and I like that even less.
So my new preferred from of exercise has become gardening and yard work. There is lots of variety of movement, bending and lifting, plus the fresh air and sunshine. I currently stay in my childhood home that has really run itself down with my mother's illness. My father loved his plants and flowerbeds. It is heartbreaking to see the weeds and vines taking over. Now is the best time because the Louisiana humidity has become too overwhelming as it will in July and August.
In the past I would have stopped after about an hour, being to tired and sore. But since beginning Paleo, I have so much energy and flexibility. I loved being in the yard today. Even if I was losing the battle. But it's early April and plenty more days to work and flex my muscles.
So get outside and play.