In boxing the ring remains idle, it is just the two combatants that are moving. In this instance the colorful streaks left by the gloves and the head gear reinforce the movement. You get a sense of where the punches came from, and where they stopped in that 1/20 of a second.
Here are images of heavyweights Malik Scott (pink head gear) and Charles Martin (red head gear) sparring at Henry Tillman Championship Boxing Club in Carson CA. Shot 2013.11.08 with Canon 5D3 and EF 24-70 f/2.8 or EF 70-200 f/2.8 lens. With a little post work in Photoshop.
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