It keeps balls from shrinking. What happens is when you take test shots, it shuts down a hormone signal from your pituitary gland called LH. (LH signals balls to make testosterone so without the signal, they shrink).
HCG mimicks the LH signal to keep your balls going.
There is no way your test rises with these over the counter bullshit products. If you think you need test, goto a clinic and get your blood work done. Then you’ll know if you need it. If you do end up getting on test, better get used to needles. 💉
I think there are two things here. Testosterone supplements and synthetic testosterone (ie TRT). I'm yet to find a natural supplement which actually boosts the natural testosterone production. But, TRT or some synthetic supplements which kill natural production have an effect though.