Purpose of a Belt
While many people think that belts are designed to prevent injury, their actual purpose is to increase intra-abdominal pressure, writes Boston-based trainer Tony Gentilcore in his article "What’s the Dealo with Weightbelts?" When you lift, you should keep your core muscles as strong and tight as possible. Pushing your abs out against a belt increases core stability and prevents your back from rounding.
The number one advantage to wearing a weight belt is safety. It won't stop you from getting injured if you lift with poor form, but the increased stability it provides may make you stronger. It can also reduce the pressure on your spine, according to Olympic weightlifting coach Nick Horton. The belt can also mentally reassure a lifter who is attempting a heavy lift.
You can become over-reliant on a belt if you wear one too often. Weightlifting belts used to be reserved for powerlifters, but now they are worn by bodybuilders and general gym-goers alike, according to strength coach Paul Chek. Overusing a weight belt can actually cause your abdominal muscles to turn off and become deconditioned, adds Chek. This increases your risk of injury when training without a belt.
Belts can be extremely useful, but you should only use them when you're lifting close to maximum weights -- around 90 percent of your single repetition maximum, advises Gentilcore. Don't use a belt for every exercise, either, adds trainer and powerlifter Dave Kirschen of Elite Fitness Systems. You still want your abs and lower back to be strong without a belt, so only use one for squats, deadlifts and standing exercises such as overhead presses.