No longer a common motivation to train second squad (5)

I believe the answer is:

steam

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'no longer a common motivation to train' is the definition.
I can't judge whether this definition defines the answer.

'second squad' is the wordplay.
'second' becomes 's' (common abbreviation).
'squad' becomes 'team' (synonyms).
's'+'team'='STEAM'

Can you help me to learn more?

(Other definitions for steam that I've seen before include "Watery vapour" , "Cook" , "Hot water suspended in air" , "Gas from boiliing water" , "Momentum - boiled water" .)

I've seen this clue in The Independent.

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