I’d have thought in general terms it is a fairly easy question to answer (without getting overly technical).
Many initial gains will come from applying what are until that point uncatered for forces on the penis area to stretch your anatomy in that area, i.e. you are stretching ligaments at the base and tissues in the penis (and internal penis) to make gains.
The act of jelqing creates increased internal blood flow pressure (i..e you are trapping blood flow and forcing it foward at greater pressure than created by a normal erection) and as a result creating damage or “micro-tears” to the penis which over time heals but by creating the damage the penis heals better able to take more blood flow and hence become larger over time.
01/08/07: 5.75" BPEL, 5.25" EG ::: 26/05/10: 7.3" BPEL, 5.4" MSEG, [My Progress Pics] - [My Routine]
Revised Min Final Objective: [/b] 7.75" BPEL (33% increase), 5.5" MSEG