The short answer is no, you do not wear underwear or knickers under padded bike shorts. The pad is designed to sit next to the skin.
3 reasons why you shouldn’t wear underwear when cycling
The seams of your own underwear can rub, causing painful chafing, which will be uncomfortable on long rides. This can also contribute to painful saddle sores.
The shorts are designed to hug your body and keep the chamois pad in the right position while you ride
The pad is designed to absorb sweat. Wearing underwear can affect how well it can do this, which in some cases can lead to a greater chance of developing a urinary tract infection (UTI)
Padded shorts will make your ride a much more comfortable experienceBikeRadar
Why do cyclists wear padded shorts?
The main purposes of padded shorts is to protect and cushion the bottom and genitals from the pressure of the body on the saddle, and to cushion the sit bones.
The pad — also known as the chamois — is designed to sit against the crotch and form a cushioning barrier between your body and the bike saddle. It also absorbs sweat away from the body.
The chamois pad usually comprises foam, gel padding and a soft fabric cover, which often has antimicrobial properties. The pad will vary in thickness to provide extra support where needed and less bulk where it’s not.
You can also find different densities and thicknesses of pad to suit different riding styles and preferences.
If you’re going for a longer ride, you may also want to use chamois cream. This is a thick cream that you put on your chamois and/or your nether regions, and is designed to help reduce the friction between skin and chamois, or skin and skin. This in turn reduces the chance of rubbing, which can become painful over a long ride. Many are also antimicrobial, which will help avoid saddle sores and UTIs.
There are two main types of padded cycling shorts: shorts and bibshorts.
Shorts, as the name suggests, are regular shorts that sit on the waist, and are made from a stretchy, supportive Lycra with a chamois pad. Bibshorts are similar to shorts but have shoulder straps to help keep them in place when riding and stops the waistband from rolling down.
Bibshorts are popular with cyclists as they sit comfortably in place thanks to the shoulder strapsThomas McDaniel
There are longer versions of both: three-quarter lengths, which are also sometimes known as ‘knickers’; and full-length, known as ‘tights’.
You can also get women’s and men’s specific shorts with cuts designed to suit different body shapes and chamois pads designed to fit the different genitalia.
Some brands also make chamois pads for different types of cycling, since the position the rider sits on the bike is different. For example, road cyclists often sit leaning forward so may need more protection towards the front of the pad, whereas mountain bikers and commuters tend to sit more upright.
You can also buy baggy shorts that come with a detachable lightweight padded Lycra liner to wear underneath.
There is also the option to have something that straddles the boundary of underwear and padded cycling shorts. These include knickers or pants for women or boxer shorts for men with a small chamois pad built in.
They are designed to be worn like regular underwear during the day, but add a little protection and cushioning for when you’re on the bike.
Designed with commuters or leisure riders in mind, they’re great for people who don’t need a full, thick chamois and don’t want to wear Lycra shorts on their commutes or short rides. They don’t look bulky under everyday clothes, so no-one needs to know you’re wearing padded underwear for cycling.
Women’s padded underwear
Louis Garneau Women’s 2002 undies
The padded knickers from Louis Garneau have a low-waist short-style designLouis Garneau