A big frustration for coaches. Even bigger for the gymnast afflicted.
Mental blocks are far more common for female athletes than male. They are most often on backwards skills. And somewhat more frequent during stressful times of the competitive season.
Every coach tries to prevent mental blocks from developing. Be particularly cautious when training backwards skills. (More matting, more progressions, more repetition.)
Some coaches have fewer mental blocks than others.
We’re learning. I believe there are fewer mental blocks in 2017 than in the past.
Rebecca Smith posted some tips.
HELP! My gymnast is afraid of going backward
Why Gymnasts Get Mental Blocks
Gymnastics Coaching.com 