The 30 Rock star joined his yoga instructor wife Hilaria at the SoulCycle Ride For Relief event, where volunteers donated as much as $1,500 (£938) to take part in the hour-long indoor fitness class.
The fundraiser pulled in more than $150,000 (£94,000), which will be used to provide aid to those in New York's Rockaway Beach, Long Beach and Staten Island after the natural disaster struck America's East Coast last month (Oct12).
In a post on her Twitter.com page, Hilaria writes, "The most amazing class SoulCycle with Alec Baldwin... Such amazing spirit and soul supporting Sandy victims... SC (SoulCycle), you've done very good!"
U.S. TV personality Kelly Ripa and Shields' writer husband Chris Henchy also tackled the stationary bike workout.