Magistrates hurry to train with the bar (5-5)

I believe the answer is:

bench-press

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'train with the bar' is the definition.
(exercise with a barbell)

'magistrates hurry' is the wordplay.
'magistrates' becomes 'bench' (I can't explain this - if you can you should believe this answer much more).
'hurry' becomes 'press'.
'bench'+'press'='BENCH-PRESS'

'to' is the link.

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I've seen this clue in The Times.

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