HERE ARE A FEW REASONS :
1. THERE’S NO WAISTBAND
Since there’s no waistband, there’s also no drawstring or itchy, uncomfortable elastic cutting into your abdomen. Your breathing will be better and therefore, you’ll feel more productive in the saddle, especially over long distances. Additionally, the traditional waistband collects and retains moisture and increases the potential for the overall likelihood of discomfort.
2. THE CHAMOIS STAYS IN PLACE
Traditional cycling shorts will end up slipping down over time, and that means the chamois, or pad, will shift as well. Keeping the chamois in place will ensure there is less potential for chafing, saddle sores, and generally unhappy times. Bib shorts by nature are designed in a way that guarantees the chamois stays perfectly in place.
3. BIB STRAPS INCREASE COMFORT
As mentioned above, bib shorts utilize lightweight, breathable mesh or Lycra straps over the shoulders. While there are a number of advantages to shoulder straps, the biggest benefit is how they comfortably hold the bib as a whole in place without creating pressure or binding points anywhere on the body. With properly fitting bib shorts you won’t feel anything tugging, binding, or chafing.
Make sure you wear bib shorts that are really designed for women. Verify the position and shape of the suspender, so that they do not interfere with your chest and make you feel uncomfortable. Check also if there is a possibility for bio-brakes without having to take off your jersey, this is a critical point to not make you feel trapped.
If you have never worn a bib short give it a try - most who do the switch never go back to a regular short with the classic waistband.