with one hand behind your back

with one hand tied behind (one's) back

Easily or effortlessly; encountering no difficulty or resistance (while doing something). I'm a professional musician, so that song is hardly a challenge—I could play it with one hand tied behind my back! Are you kidding? Montgomery is a powerhouse boxer. He'd knock that kid out with both hands tied behind his back!
See also: back, behind, hand, one, tie
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

with one hand (tied) behind your back

1 with serious limitations or restrictions. 2 used to indicate that you could do something without any difficulty.
See also: back, behind, hand, one
Farlex Partner Idioms Dictionary © Farlex 2017
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References in periodicals archive ?
Caption: Stand or sit with one hand behind your back. Place your other hand on your head and gently pull your chin towards your armpit.
If you're an AE or AT, do you remember being told in "A" school that you should work with one hand behind your back while working on energized circuits?
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