Processed carbs are the greatest contributors to dietary problems and anathema to the paleo diet. Is there an equivalent in exercise?
Just as there are poor ways to eat, are there poor ways to exercise? Or is exercise different because any type of exercise is beneficial?
I would also add extreme supplement-driven bodybuilding to the Chronic Cardio answers. Anything where you are chugging shakes that don't remotely resemble real food and popping a ton of lab-sourced pills to force yourself into a shape and bodyfat % that our ancestors would never have seen.
Lifting heavy things is fine, lifting heavy things to extreme, focusing on big muscle appearance rather than actual strength, and sticking chemicals in your body is too far.
There's no more one right way for everyone to exercise than there is one right way for everyone to eat. Some combination of aerobic, anaerobic, and resistance training will work best for you, determined in the same way that evolution determines fitness: Trial and error.
I'm a chronic cardio addict so am extremely biased; I'd say isolated weight machines before cardio, I bet our caveman ancestors ran for distance before they sat on a rock and strength trained specific muscles!
I'm currently doing a little N=1 on myself with adding a little cycling/cardio back in the mix. Interestingly enough, on my second ride (btw, just adding it a couple times per week JUST to see how I react) going about 22 miles of "hilly" riding (1 1/2 hours or so), I came back home afterward and did an afternoon/evening binge feast of just about everything in the house. Nothing too terrible, but some left over GF crackers from a shower over the weekend (damn those things!), WAY more fruit than normal, nuts galore, more fruit, some tuna, other lunch meats, and more nuts. Likely 3x+ the normal amount of food I would have throughout the day. I love to do this to mix it up and I do think doing a run or a ride once ever week or two is fine. I just know for me it might mean being on the "tread mill of life" to support this way of "exercise"...like I might be running/riding my way away from food - constantly.
I think our bodies are all different and react differently, but I'm thinking I like the intense type of workout a couple times a week with some sprints and lots of movement.