The FIG Sport Science Commission has a database of reputable peer reviewed journals citations including “Gymnastics” as one of the key words or tags.
They are collecting PDFs of those citations now.
Sample:
Role of Intensive Training in the Growth and Maturation of Artistic Gymnasts (PDF)
If you are aware of any private collections of PDF citations, or have one yourself, you could contact me.
RickMcCharles (a) gmail.com
Private collections can be shared.
Gymnastics Coaching.com 