E-bikes can be a useful part of cardiac rehabilitation programmes, since health professionals will often recommend a stationary bike be used in the early stages of these. Exercise-based cardiac rehabilitation programmes can reduce deaths in people with coronary heart disease by around 27%;[55] and a patient may feel safer progressing from stationary bikes to e-bikes.[56] They require less cardiac exertion for those who have experienced heart problems.[57]

If you’re interested in an ebike, you have a couple of options: converting your existing bike or buying an electric version. Abadie says a bike suitable for conversion will have a powerful brake system, wider tires and a strong frame that can hold the motor and battery. He charges $800 to $1,200 to find the right parts and motors for a particular bike.
Using an electric bike for long-distance touring has its pros and cons. The motor will help carry the extra weight of your kit, particularly on the hills, but you have the added hassle of having to charge the battery every night. You’ll want a powerful motor and a good battery, though if you’re fully loaded, don’t expect to achieve the maximum advertised range.
Gearing: none (many hub motors, one motor revolution = one wheel revolution), fixed gear reduction for more torque, varies when geared motor drives the chain through the bicycle gears which increases torque about 50% (in low gear) for better hill-climbing and offers better top-end speed (in high gear) than direct drive systems using motors of similar wattage.
For many bikes, battery range is more important that total power (because they're all pretty powerful). You want a bike that delivers a range long enough for your rides at the power levels you want. Most e-bikes will have three to five levels of assist kicking in anywhere from 25 percent of you pedal power to 200 percent boost. Consider how fast the battery takes to recharge, especially if you'll be using your bike for long commutes.