Some good references on this to look at:

Ski Faster, Ski Easier -- Lee Borowski
One Stride Ahead -- Marty Hall
How to, When to,... -- Torbjorn Karlsen
Getting Stronger -- Bill Pearl (a few pages of cross country skiing
programs for off-, pre- and in-season by Steve Gaskill, Peter Ashley and
T Karlsen in my early edition).

The first two can often be had inexpensively at the used book sites:
abebooks.com, alibris.com, and they are both excellent all-around books
from the '80s.

Gene

alexmal wrote:

wrote in message roups.com...
I go twice a week

so there is no special ski-set in i-net?