How? If you plan to lift heavy weights, get the help of two spotters. Then lie back on the Swiss ball with your feet flat on the floor, your back in a neutral position and your core braced. Hold a dumb-bell in each hand, palms out, then drive the weights straight up in line with your chest, exhaling as you go. Then lower the weight in your right hand as far as possible and drive it up again so that both weights are up in the air. Now lower the left-hand dumb-bell and repeat.

Why? ‘The dumb-bell bench press recruits a whole stack of muscle fibres to stabilise the weight in each hand,’ says strength and conditioning coach Nick Grantham. ‘And by alternating the dumb-bells from their “up” position, you make the resting arm, shoulder and pectoral muscle work to hold the weight in its static position. This active rest holds tension in the muscles. Because you’re making the weight work harder you won’t be able to lift as much as usual, reducing the chances of injuring your shoulder joint as you actively strengthen it.’