The following are lab results for free testosterone before and after the usage of Sumatra Pasak Bumi's 1:200 tongkat ali extract.

Before tongkat ali usage, the trial participant's levels of free testosterone have been determined by the university hospital at Koeln, Germany, to be 15.4 pg/ml. After 4 month of usage of tongkat ali extract, the plasma level of free testosterone was measured as 49.20 pg/ml.

Before tongkat ali

After tongkat ali