Just finished reading "Burn" by a Harvard PhD focused on metabolism. (Amazon product ASIN B08D8JYQD6).
The main point is that most humans burn a similar number of calories daily whether they are sedentary Americans taking 5,000 steps a day or Hadza hunter-gathers taking 16,000 steps a day. Humans have had high physical activity levels for millions of years, so even though we suddenly stopped exercising in the last 100 years or so, the body doesn't really ramp down its caloric spend. If we exercise less, we'll just spend more calories on potentially harmful uses such as generating excessive inflammation and excessive sex hormones (testosterone and estrogen).
I've never heard about higher testosterone being a bad thing, but he argues that hunter-gather men and Western endurance athletes have lower test levels. He argues that these lower test levels aren't a bad thing. He does say that most Hadza women have children on average 3 years apart vs. Western women who are ready after about 1 year, but I don't think he's arguing that the low test levels lead to the men having ED or lower quality sperm.
Anyway, the book's generally written with a bioenergetic lens, and it's an interesting counter to the prevailing logic of "if you eat more and exercise less, your body will have more energy to spend on non-essential uses like regrowing your hair."
The main point is that most humans burn a similar number of calories daily whether they are sedentary Americans taking 5,000 steps a day or Hadza hunter-gathers taking 16,000 steps a day. Humans have had high physical activity levels for millions of years, so even though we suddenly stopped exercising in the last 100 years or so, the body doesn't really ramp down its caloric spend. If we exercise less, we'll just spend more calories on potentially harmful uses such as generating excessive inflammation and excessive sex hormones (testosterone and estrogen).
I've never heard about higher testosterone being a bad thing, but he argues that hunter-gather men and Western endurance athletes have lower test levels. He argues that these lower test levels aren't a bad thing. He does say that most Hadza women have children on average 3 years apart vs. Western women who are ready after about 1 year, but I don't think he's arguing that the low test levels lead to the men having ED or lower quality sperm.
Anyway, the book's generally written with a bioenergetic lens, and it's an interesting counter to the prevailing logic of "if you eat more and exercise less, your body will have more energy to spend on non-essential uses like regrowing your hair."
