What is Cross Country
There are several varieties of XC skiing. The most obvious differences are those between skating and diagonal stride,or `classic' nordic skiing.
If you have never seen skate skiing, its side-to-side pushoffs resemble speed skating or rollerblading but with the addition of tall (roughtly chin height) poles for added speed. It's fast and someone that is good at it can look like they are lazily flying over flat ground. The amount of energy it takes to skate varies widely with the terrain, with a competent skater using relatively little energy when going over flat ground but quite a lot if they are trying to go uphill fast. Skating is an excellent means for developing dynamic balance, since mostskating techniques require that the skier glide on only one foot for a few seconds. Skating requires a wide groomed trail that has been packed down, usually by machine. Skating skis are narrow and light, making them unsuitable for use in the deeper unbroken snows of the backcountry.
Diagonal stride, on the other hand, looks more like a gliding walk with shoulder-height poles and exaggerated arm and leg movements. The movement of someone on a Nordic Trak machine in a health club is a very rough approximation to the rhythmic and flowing motion of a skilled classic nordic skier. The diagonal stride is a bit slower than skating and can be done in intensities that range from a gliding shuffle to a fast run. The amount of energy it takes doesn't vary as much with terrain as it does with skating, so going up most hills takes about as much energy as walking briskly up a flight of stairs. Diagonal stride can be done in almost any terrain, from machine set tracks at a commercial ski area to untouched backcountry snowfields. Commercial and government maintained ski areas offer maps, the relative safety of well marked ski trails, the company of other skiers, ski lodges, and warming huts out along the trail. Backcountry skiing offers more quiet, more solitude, a bit more risk if you are not careful, and more wildlife and raw nature.
This is a downhill only technique, but unlike most alpine skiing, this is done with boots and bindings that don't lock down at the heel. When done well, it is both graceful and stable, and can be adapted to range from from broad carving turns on open slopes to sharp and quick jump turns on some of the most extreme slopes anywhere.