Shoes don’t produce power — the rower does. But footwear can change how the feet connect to the footstretcher, which is where the leg drive begins.
Erging without shoes removes the cushioning and raised heel that most running shoes have. That may help a rower notice where pressure is going through the foot, or whether they’re driving through the whole foot instead of staying up on the toes. Still, there isn’t enough evidence that a cushioned sole absorbs a meaningful amount of rowing power.
The stronger argument is positioning. Concept2 recommends rowing without shoes or in flat, thin-soled shoes, since a thick heel changes the angle of the foot and raises it on the machine — which can put the foot in a weaker driving position and cause knee discomfort for some rowers (“Find Your Optimal Foot Position”).
Small setup changes affect stroke quality, too. In a study of ten male rowers, researchers tested four footstretcher heights and found that raising the feet progressively reduced horizontal foot force, stroke length, and pelvic movement (Buckeridge et al., 2016).
Shoes have real advantages of their own — they protect the heels, keep socks from slipping, and make long sessions more comfortable. Concept2 recommends grippy socks or extra heel padding for anyone rowing barefoot on hard heel cups or dirty footplates (“Getting Comfortable”).
A flat, minimal training shoe is a reasonable middle ground. Erging without shoes may sharpen awareness of foot pressure, but it isn’t a shortcut to a faster score — and if you do switch to socks, the footstretcher may need to move about one setting higher to make up for the missing sole.
My coach’s choice to erg without shoes comes down to personal preference. He may be right that the leg drive feels more direct without them, but that doesn’t necessarily make it faster — the best option is whatever keeps the feet stable, comfortable, and properly positioned. For most rowers, consistent technique matters far more than what they wear on their feet.