Picking your next skis is not as simple as it used to be.

When buying skis, choose a ski based on matching width and turn radius to the kind of snow you like.

Hard snow: select a ski with a narrow waist – 76mm or narrower.

Soft groomers (or general western front-of-mountain skiing): select a moderate waist – 75 to 85mm.

Resort powder (with firm surface underneath): select a mid-fat waist – 85 to 90mm.

Deep snow (with unpredictable base beneath): select a fat waist – more than 90mm. If you’re big and heavy or carry a heavy pack, go even bigger – 100mm+.

The remaining decisions are length and shape. Most men skiing at resorts can get along nicely on a 165cm ski; most women on 155cm. If you’re stronger than average, go a bit longer, but it won’t buy you a lot of additional stability. If you’re much lighter than average, go a bit shorter. It will pay off in improved agility.

Shape means sidecut. A deeper sidecut with a shorter radius carves a shorter turn. In general, this helps best on groomers. It won’t help in bumps, where you want the tail to release to avoid hanging up at the end of the turn. A good mid-fat has a shape close to 115-80-105, which gives a theoretical radius of about 14 meters and a bearing surface — the ski’s ability to “float” on soft snow — of 1350 cm2. Furthermore, the mid-fat’s agility — its ability to bend easily into a turn — is vastly improved because it has a short turn radius.

Each dimension can be varied in different ski types. Know your preferences.
Credit: Brittanica

What shape should you buy? Start with a “generic” 115-80-105mm shape at your length, then select a wider waist if you’re going to ski a lot of soft snow, or a narrower one if you’re going to ski a lot of hard snow. If you’re an expert who loves to carve, go for a shorter radius. If you want to be able to slide the tail a bit in bumps and tight woods (or if you have to skid a bit when you teach intermediates) opt for a slightly narrower tail.

Seth Masia, former technical editor of SKI magazine, heads the Ski Younger Now program at Vail Village. Ski Younger Now is a retraining program for older skiers, and skiers returning to the sport after recovering from an injury. It teaches low-impact, low-torque techniques to enable efficient skiing in all kinds of terrain.

The workshops are scheduled for December 15-17, 2015; January 12-14, 2016; February 16-18; and March 8-10. To schedule or learn more, email sethmasia@gmail.com or call Vail Village Private Lesson Desk (800) 475-4543 and ask for Seth Masia.