While recumbents are the most comfortable bikes out there (the cycling position is like that of a recliner chair), the big question is, is that what you want? I mean, sure, if you’re trying to rehabilitate an injury or if you’re seriously out of shape, but otherwise, we think that most people are served better with a spin bike. This is especially true if you’re in this for the long haul as people that stick to cycling workouts shed the extra pounds quickly. Might as well invest in a high-performance product that improves your road worthiness should you consider riding a bike outdoors at some point .
The Sun does not have a definite boundary, but its density decreases exponentially with increasing height above the photosphere .  For the purpose of measurement, however, the Sun's radius is considered to be the distance from its center to the edge of the photosphere, the apparent visible surface of the Sun.  By this measure, the Sun is a near-perfect sphere with an oblateness estimated at about 9 millionths,  which means that its polar diameter differs from its equatorial diameter by only 10 kilometres ( mi).  The tidal effect of the planets is weak and does not significantly affect the shape of the Sun.  The Sun rotates faster at its equator than at its poles . This differential rotation is caused by convective motion due to heat transport and the Coriolis force due to the Sun's rotation. In a frame of reference defined by the stars, the rotational period is approximately days at the equator and days at the poles. Viewed from Earth as it orbits the Sun, the apparent rotational period of the Sun at its equator is about 28 days.