They might look like simple plastic discs, but a personal trainer says core sliders are the most underrated fitness tools to tone your abs, arms and glutes.

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." Nordic curls are a bit of a gymgoer’s party trick. As you lower the backside of your body backwards ...

Women's Health may earn commission from the links on this page, but we only feature products we believe in. Why Trust Us? Nordic curls are a bit of a gymgoer’s party trick. As you lower the backside ...