Take the 2-minute tour ×  I've just started a HIIT training
routine and after two workouts my arms (triceps & biceps) grew
1/4 inch. I went to the gym this morning and after I got home 12
hours later measured my arms and they'd shrunk by 1/8th of an
inch.  I know that muscles grow when I rest and sleep. But will
the gain return in the morning? And is the shrinkage a sign of
possible over training? I haven't trained to failure in any of
my muscle groups in the last week.  share|improve this question
Did you take your first measurement after you had worked out?
Right after a workout the muscles are filled with blood (we call
this the pump). This is a temporary thing and will go down after
you train. Try to always take your measurements either directly
after a workout, or before - be consistant. –  ElvisLikeBear Nov
27 '12 at 2:49 add comment  1 Answer  up vote 2 down vote
accepted  Several things can affect the size and makeup of your
muscles:    • What you eat. Eating carbs post workout can help
increase the s