What does academic research say about the relationship between squats and hGH/Testoterone?

Question

I hear a lot of advocacy of squats as a method for producing testosterone and human growth hormone as part of exercise-induced muscle hypertrophy.

I cannot, however, find any academic research on this question outside of anecdotal evidence. Is there any research to suggest that squats are the most effective exercise at producing hGH and testosterone? What other exercises do this?

**Note, I am not skeptical of the claim that the total work done during a particular exercise is related to hGH output-- I am skeptical of the claim that squats are significantly MORE effective than other exercises at inducing higher postexercise hGH blood levels. I am wondering if there is evidence explicating the degree to which certain compound exercises contribute to blood-serum hGH levels.

Answer 1

I haven't been able to find any research specifically targeting a squat routine versus a different muscle group routine either, so some of this will be inference. I'd theorize that squats are designated as prime exercises simply because they are some of the largest, strongest muscles in the body, so they will have the largest overall response. This is in part corroborated by some of the studies comparing both men and women, or young/old men on the same exercise protocol, which could be attributed to the generally smaller muscle size between the sexes/ages.

Here's the studies that I read through, which also suggest that higher reps with less weight/rest (i.e. more total work than maximal, most compared 5 rep with 3 min rest vs 10 rep with 1 min rest, near maximal vs. 70%) produced higher differences in serum hormones. None, however, specifically address squats compared to other exercises.

Male and female comparison

Young vs. older men

Total work differences

Women only study

Max vs. 70% work in trained athletes