As a form of cardio exercise recognized by the American Heart Association, roller skating gets your ticker pumping. This low-impact workout goes easy on the joints but burns about 330 to 600 calories per hour, depending on the intensity of the exercise. To achieve high intensity, you can take your skates to the great outdoors, but you'll need wheels that are a little different than your typical rink-oriented rollers.
Most importantly, indoor and outdoor roller skate wheels differ in hardness. Indoor wheels, which cater to smooth surfaces such as rinks, are much harder than rubbery outdoor wheels. This allows indoor wheels to glide quickly over smooth, hard ground, but makes them liable to slipping and sliding over rough or irregular terrain. On the flip side, softer outdoor wheels have plenty of grip. Skate manufacturers use the durometer scale to measure wheel hardness; the bigger the number, the harder the wheel. Most indoor wheels range in hardness from 88A to 103A. For outdoor use, it's best to stick with wheels rated 90A or below.
Skate wheels run the size gamut from about 54 millimeters to 84 mm, measured in height. While indoor wheels range in size from about 55 mm to 60 mm, outdoor wheels go big, with sizes ranging from about 60 mm to 70 mm. The larger size of outdoor wheels allows them to roll over bumps and absorb more shock than their indoor brethren, whose smaller size allows for on-the-dime turns.
Virtually any sort of quad-wheel skate boot accommodates outdoor wheels, so you're not limited to one type -- you can change your wheels depending on the situation. But if you tend to skate outdoors more than indoors, you may want to look into outdoor skate boots, which typically feature higher tops and rugged, easy-to-clean construction. Hybrid wheels offer an all-terrain middle ground, catering to use in both indoor and outdoor environments. In comparison to dedicated indoor or outdoor wheels, however, these wheels are a bit slow inside and don't offer the strongest outdoor grip.
For the most part, skate wheels on either side of the spectrum won't break the bank. At the time of publication, indoor skate wheels range from about $4 to $50, and outdoor wheels range from about $3 to $40. For both types, manufacturers offer professional-quality wheels, which can cost you anywhere from $50 to $120. Wheels usually come in sets of four or eight.
Dan Ketchum has been a professional writer since 2003, with work appearing online and offline in Word Riot, Bazooka Magazine, Anemone Sidecar, Trails and more. Dan's diverse professional background spans from costume design and screenwriting to mixology, manual labor and video game industry publicity.