Your body’s biggest enemy? Time. You can smash double-your-bodyweight deadlifts, but deadlines keep you out of the gym and in your takeaway’s VIP club. Both of which are bad news for your six-pack. But train right and less work can be a whole lot more effective. “It’s all about intensity,” says Dylan Jones, founder of P4 Body training, and a man who used to whip elite soldiers into shape. As Jones points out – and a quick scout of your gym proves – half of most sessions are spent sitting down. Cut those rest periods and you spike your heart rate and metabolism. So a brief burst of exercise gives 36 hours of boosted calorie burn. “If you’re doing this kind of circuit, at the right level of intensity, you don’t need to train for more than 20 minutes,” says Jones. In fact, if you can go longer, then you’re not working hard enough. That means you need to tackle something more taxing than bicep curls. “It’s about moves that offer the biggest bang for your buck.” By targeting the big muscles in your legs and back, you torch more calories, in less time. But time pressures don’t mean you can cut corners. “If you only put 50 per cent in, you’re only going to get 50 per cent out,” says Jones. “Perfect form makes the exercises harder and more effective.” A quick warm-up is also vital. “Otherwise you waste your first set as your muscles fire up.” Start with five minutes of dynamic stretching – think lunges, inchworms and lateral bounds – then tackle the circuit. Remember: the more you sweat, the more fat you burn.

Dylan Jones’ 20-Minute Body Shred

“Your rest periods define how hard the workout is,” says Jones. Start with 30 seconds of exercise, 30 seconds of rest. As you improve, cut your rest and extend your activity – 40 on, 20 off, then 50 on, 10 off. If you’ve got access to a sandpit, great. “The instability makes your body work harder,” says Jones. If not, grass will prove just as taxing. https://www.youtube.com/watch?v=2L7u8m3wVOM&feature=youtu.be Perform one set of each exercise, then rest before moving onto the next. After the V-sits, return to the high knees. Repeat the entire circuit three times.