Yep! It's joked that we "walked" our prey to death, and that's pretty much true.
To an animal, we're this eldritch thing that doesn't stop following them until they simply drop from exhaustion.
And, IIRC, we technically are as strong as chimpanzees -- it's just our brains evolved to literally control how much strength we use to not tear ourselves apart.
All those cases where mothers lifted cars off their kids? Yeah, that's basically always from an override of that mechanism, not just adrenaline.
Humans are pound for pound not as strong as chimpanzees. And no, it's not because of how we "control how much strength we use". It is because the way a chimanzee's frame is, compared to a humans. Their long torso's, powerful backs, and very long arms give them a mechanical, leverage advantage over humans. Bones, tendons, and attachments equate to leverage - muscles and type of muscle fibers are only secondary.
With that said, there is quite a bit of diversity in human frame structures - some people (and dare i say, some groups of people) are naturally much stronger and more athletic than others.
Not really. Modern humans are on average way, way overweight. Average paleolithic hunter would be some 150 lbs, I would think... they were shorter than today's people, and main advantage humans have over other animals are our brains and endurance. Chimpanzee is three times stronger than a human, because our muscles are set up for endurance and control more than strength.
Not even getting into the average sizes of paleolithic hunters. However, the natives of the northern American plains were said to be the largest men on earth in the 1800s. The men averaged roughly 5'11 inches in height with solid frames and, I would reckon, were in trim, athletic running shape at anywhere from 155 to 185 pounds. Some taller and larger framed men could have weighed more - they had the hearty diet to grow larger in frame and be healthy at larger frames and keep at a healthy weight
The average American man, today? Well - and this isn't a widely discussed thought - but there really is no "average American size", given that, say, men of German/Dutch/Scandinavian ancestry from the mid-west, are going to be considerably taller on average than, say, men of Guatemalan ancestry. A big gap there, I know, but genetics is everything. Nevertheless, a 5'5'' man in trim, athletic running shape, assuming he has a normal frame (not overly robust, nor overly flimsy), will probably weigh anywhere from 125 to 135 pounds. A 5'10'' man of the same frame type? probably anywhere from 145 to 165 pounds
Humans are big - but not anywhere near as big as the overweight "averages" of modern sedentary humans suggest. Not to mention most people lie about their heights, always measure with shoes on, and round up.
EDIT: Here is what a 6'5'' inch man (Chuck Connors) looks like when in trim, athletic running shape - without excess muscle or fat - being listed at weighing 190 pounds during his playing career
Here is Max Baer (6'2''), listed at 208 pounds for most of his career