This is a great "bang for your buck" exercise that kills a bunch of birds with one stone. Think of it as a moving plank. To start off, don't use the sled like you see in the video. Just start with your bodyweight.

Start in plank position with your forearms on the ground and your feet on a pair of sliders. Crawl forward while trying to keep your torso and hips as still as possible. To do this successfully, you really have to brace your core and squeeze your glutes the entire time.

Now add load. Wearing a weighted vest can lead to wrist and elbow pain, so it's better to drag the weight behind you either by putting your feet on a weight plate, or if you're really masochistic, dragging a weighted sled.

These will also jack your heart rate up, making them a great finishing exercise for the end of an upper body workout. The obvious drawback to this one is that it requires both space and specialized equipment, which not everyone has. If you do though, definitely give these a try.

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