Regular deep tissue massages are extremely beneficial to the average gym-goer, athlete or bodybuilder. Taking just a 30-45 minute body massage once every 3-4 months will keep your muscles in optimal working order.
One of the main benefits of taking a massage will be increased muscle definition, muscles that are damaged, forever sore, or injured do not hold blood as well as a fully functioning one. Remember that all your nutrients that you get from food, are carried in the bloodstream.
You will feel more flexible, free and agile. Loosening up your joints will help with your range of motion, especially around your shoulder/delt area. Increasing your range of motion just a few more inches on each rep can be the difference between average biceps, and bulging peaking guns!
Applying pressure to your muscles helps clear out lactic acid, in turn allowing more Oxygen and blood flow in that particular area.
Terms vary worldwide, ensure the practioner knows what/why you have come:
In the UK you may want to ask for a 'Sports Massage'
In the USA you may want to ask for a 'Deep Tissue Massage'
In Australia, you are probably lucky enough to have a specialist 'Thai Massage' Business close by - which is the best type of massage I would recommend.
Either way - ensure you do not get a 'beauty' style massage which is more a softer, surface area style treatment, which doesn't target the ligaments, tendons and inner muscle which the bodybuilder regularly works.