Suitable starters for footballers in training (3)
I believe the answer is:
fit
'suitable' is the definition.
(similar in meaning)
'starters for footballers in training' is the wordplay.
'starters for' says to take the initial letters.
The first letters of 'footballers in training' is 'FIT'.
(Other definitions for fit that I've seen before include "'Sudden attack, of coughing say (3)'" , "Sudden attack,of coughing say" , "In good shape; sudden attack" , "Attractive" , "Strong" .)