When I first tried a 16" box jump it was pitiful to say the least :-(
Having Fibromyalgia I have an enhanced alertness to danger, so making a substantial jump like this when you're body is trying its best to hold you back is very difficult.
I was not ready 4 weeks ago, I needed to continue adding strength to my legs and also desensitize myself by growing my confidence. I started by box-jumping using a Reebok Step. It was so difficult, felt so unnatural, my brain was not happy, but I persisted.
Today I decided to try the 16 inch box and BOOOOM, 3Sets 12 Reps!!!
The moral of this story for me is that "Gains Don't Come For Free"
Stick that on a T-shirt Scott #HTH
James