'To get Robert Downey Jr in shape to play Sherlock Holmes we did high-volume, low-intensity workouts to build his cardio levels and muscle endurance,' says Robert Downey Jr's legendary American trainer Brad Bose. 'I didn't want him to get huge, but he needed to be fit enough to do his own stunts. To achieve this we used a machine called the Vortex Perfect Storm, a free-standing multi-gym that has loads of attachments for cables and resistance.

'We'd do intervals on the Perfect Storm, hitting his major muscle groups from loads of different angles, then finish up with a climb on a Jacob's Ladder – an inclined climbing treadmill – to improve his cardio,' says Bose.

It clearly worked - you can see in the picture above just how fit Robert Downey Jr looked after doing this routine. Not everyone has access to a Vortex Perfect Storm or a Jacob's Ladder, of course, but you can still get a body like Robert Downey Jr's by doing our workout on the right. The key to it is keeping the volume high and going through each set at a steady pace. Do five minutes on a rowing machine as a warm-up and take as little rest between sets as you can handle.

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