This article originally appeared in Shape.
When you're in the mood for a full-body, fast-paced workout, you probably head online for high-intensity interval training (HIIT) workout videos. But when your WiFi's on the fritz and non-stop buffering is ruining your sweat sesh, you're not totally S.O.L.
These 13 HIIT exercises are a gift from Amanda Butler, a New York City-based personal trainer formerly with The Fhitting Room (a studio dedicated to HIIT workouts). By combining these killer moves into one routine, you get a homemade HIIT workout that burns calories and fires up your muscles.
How it works: Perform each equipment-free exercise for a minute, followed by a minute of rest.
You'll need: No equipment, just some space.