Advice needed for my other half, wanting to build muscle.

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So he's looking to build muscle and blast his stomach fat.

He is currently doing Insanity again after a long break from working out at all followed by 15-20 minutes of sit ups, push ups, squats, lunges and about 20-25 minutes lifting weights (all at home)

He has 2 protein shakes a day.
His diet isn't the best in the world neither is it the worst, he works shifts and is gone 12 hours a day at work.

Any advice on what weight routine for him to try out would be great and advice from guys who also work long hours and still manage to get ripped :happy: :happy: :happy: