This content is from the experts at Men's Fitness magazine.
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Resting your knees on the floor removes some of your bodyweight from the move, making this a great way to start building upper-body strength.
Placing your hands slightly wider will reduce the range of motion, making each rep a bit easier. It also places greater emphasis on the chest and less on the triceps, which are a weak spot for some.
Place your hands just wider than shoulder-width apart with your body in a straight line from head to heels. As you lower keep your elbows pointing back, not to the sides.
Touching the tips of opposite thumbs and index fingers together turns this into a great triceps-sculpting move.
Twisting and raising your arms alternately after each rep forces your core to work harder to stabilise your body.
Lift one leg off the ground and perform the set as normal to work your core, glutes and leg muscles.
Jumping your hands alternately backwards and forwards hits your chest and triceps muscles from different angles.
Pushing up hard so that your hands leave the floor helps develop explosive upper-body strength and power.
Pushing up explosively after each rep so that you can clap your hands recruits more fast-twitch muscle fibres, which leads to greater size and strength gains.
The ultimate show-off move, performing press-ups with only one arm requires great upper-body strength and stability because your core must keep your torso steady so that you can complete each rep without falling over.
Done the others? Then try this, the hardest press-up known to man.
Doing a press-up with your feet off the ground requires phenomenal strength, balance and co-ordination. Place your hands by your hips, lean forward, lift your legs off the ground, press up and start counting!