Tens of millions of Americans maintain their health through cycling - a low impact, non-weightbearing and fun aerobic sport. Because cycling never becomes boring or repetitive, many do it for life. As a fitness activity, cycling's only downside is that one must either ride alone or find someone of similar ability. Imagine how much more fulfilling cycling would be if we could share a workout with faster or slower partners - it might become the best fitness activity ever.

And for families, the choice is even tougher. Do you spend your time working out or do you spend time with loved ones? On single bikes, it's frustrating (if not impossible) to ride with kids and spouses. Tandems, however, combine the efforts of any two people - allowing either person to pedal with as much or little force as they desire - and blend them into a seamless performance. By transcending skill, experience and ability, tandems are the ultimate family bikes.

A few years ago, the best bicycles-built-for-two were clunky, unwieldy and totally unsatisfactory. Today's best tandems, by comparison, are anything but. With proper design, tubing and components, a tandem, by virtue of its weight and wheelbase, is exceptionally safe and stable. Compared to single bikes, good tandems are also faster and more comfortable. Two can ride more easily than one.

Most cyclists first learn about a tandem's speed when riding behind one on an organized ride. Then, we notice that even while single bikers are struggling to keep up, the tandem's riders are sharing a normal conversation. When confronted with this contradictory image of speed and leisure, most people assume the tandem's owners must be incredibly fit. After all, cycling can't be this efficient, there must be a catch. But that's what it's like on a tandem, you can ride faster and farther with less work.

How many activities can couples share where both look equally stylish, graceful and capable? While most activities reveal our differences in strength, style and grace, every couple looks great on a tandem. (We call this the Fred and Ginger factor.)

Where does a tandem's speed come from? Because tandems cut per-rider wind and rolling resistance virtually in half - even a fat-tired mountain tandem is more efficient than the sleekest disc-wheeled single bike. Further, when two cyclists ride together on singles, they are limited by the speed and range of the slower rider. Tandem partners, however, automatically attain or exceed the speed and range of the faster rider. This near-doubling of horsepower allows tandem partners to enjoy longer tours and faster training rides. Many tandem couples, even seniors, are delighted to find themselves routinely pulling long pacelines of young riders.

Because tandems are more aerodynamic when the taller rider captains, with most mixed couples this means the man rides in front. Regardless of gender, stokers need never feel ìstuckî in back. To the contrary, cyclists with equal time on both ends of a tandem unanimously prefer stoking - it's more fun! Unlike their captain (and single bike riders), stokers won't spend two-thirds of their time staring at that small piece of road directly in front of their front wheel (vigilantly watching for rocks, potholes, glass, rear wheels of other riders and about-to-open car doors). Because stokers don't watch the road in front, steer, shift or use the brakes, they discover a new sense of freedom. Stokers can ride no-hands, chat with other riders, read maps, study the scenery, point out wildlife and even examine the insides of their eyelids.