Davan is right. At your age you have all hormones flowing you need. And no over-the-counter test booster would help as much as a little more dedication, a little better nutrition, and and a little more sleep. Those things are free and good for you. Unregulated supplements are expensive and good do more harm than good. Now, stop reading this post and go work out.
I just turned 29 and I have used a few test boosters in the past year or two. Before that would be pointless IMO. In fact the only reason I took them was to keep testosterone up to par while in an very large calorie deficit. Under normal circumstances, with a sound diet and recovery protocol, your recovery should be just fun. I would however say that ZMA is useful for any athlete over 18.
Wouldn’t divanil be effective at any age though for increasing free T?
How much time is it going to take off of your 60m, 100m, 200m and how much will it increase your lifts?
If it sounds too good to be true, it probably is and if anything was incredibly effective and induced great results in healthy young males, it would be made illegal by now and/or some pharmaceutical company would have figured out a way to sell it as hormone replacement therapy.