Robert Downey Jr. just gave fans a look on Instagram of how he got into top shape to play Tony Stark in the movie Avengers: Infinity War.
In his training video, which he shared on Instagram, Downey completes a roped sled pull—which copies the classic row that you might use a dumbbell for—and then the actor turns the exercise into a sled push.
“Basically that is a really great row,” says Men’s Health director Ebenezer Samuel, “It’s more fun than rows with a dumbbell or on a machine.
The best part is that it gets rotational as a row (meaning your torso moves back and forth), so it’s important for the person to create movement from the right spots.
Rotate at your shoulder blades and chest first, and try to maintain your hips to protect your lower back.”
Sled training is a powerful but pain-free exercise used to build muscle and burn fat, and is a favorite of many Hollywood stars.
But Samuel continues by saying the benefits of the move is made better when used paired with a wider group of exercises.
“The problem is that you miss two vital contractions,” he says. “You get a strong concentric as you go back, but you don’t get eccentric or isometric contractions. So use moves like this, but keep your dumbbell rows too.”