[R] lmer formula

[R Heberto Ghezzo, Dr]

Hello,
I have some problems trying to write up the formula for lmer.
I have 43 subjects ( random factor) which were seen twice ( Visit : repeated measure - fixed). on each visit the patient performed a graded effort exercise ( effort : repeated measures, ordered,  fixed 4 levels).
So Subject is a random factor, Effort is crossed with Visit and both are repeated measures, the efforts are ordered as it is a cummulative test.
The model
y ~ Visit * Effort + (Visit | Subject) + (Effort | Subject) 
seems appropriate but how can I get a linear-quadratic trend for effort? 
Also the Covar matrix for the repeated measures is 8 by 8 . It is not blocked beacuse there is the possibility of a learning effect between the visits. How can I specify this?
Thanks for any help with this model.
Heberto Ghezzo Ph.D.
Meakins-Christie Labs
Mc Gill University
Montreal - Canada