Handlebars have a considerable impact on comfort and aerodynamics. Therefore, the position greatly differs between recreational and competitive cyclists. The position you choose for your handlebars should always allow you to keep your shoulders relaxed, especially the upper trapezius (muscle on top of the shoulder).
The handlebars of a recreational rider should be positioned so that the trunk is bent forward by 10° to 40° from the vertical. The hands should be slightly wider than the shoulders. This more upright position reduces the stress on the arms, shoulder, neck and back but is not as aerodynamic.To improve aerodynamics the trunk needs more forward lean and should be inclined forward by 50° to 60° with the hands about 2 cm wider than the shoulders.
The Body and The Bike 