If you’re dieting
Combining weights with cardio is a formula for weight maintenance. Strength training and weight-bearing training will maintain muscle mass as weight drops. Without strength training your caloric deficit will cause catabolism, causing metabolic rate to inch lower, making it easier to gain weight later.
“You can burn quite a lot of calories during half an hour jogging on the treadmill at medium pace. If you do half an hour of strength training you’ll probably burn less calories during that half an hour, but you would continue to burn your calories for the next 24 to 48 hours after you completed your exercise,” Richard Garard, founder of She Fitness says. That’s the beauty of EPOC (excess post-exercise oxygen consumption).
If you’re busy
You’ve heard it before, but HIIT really is like skipping the queue. The interval protocol “has your heart rate go up high and then rest, you burn more calories and get a bigger response through your workout in a shorter period of time and you can basically go hard, then rest, go hard and then rest, or you can have a fairly long workout.”
In other words, optimal duration depends on intensity. After HIIT “your body has to fight really hard after your workout to try and repair itself, so it’s using a lot of energy and your metabolism ends up spiking through the roof.”
In a famous study by Tabata et al, participants who undertook a four-minute interval training session comprising eight 20-second hard efforts broken by 10-second recoveries five days a week showed a 28 per cent improvement in fitness in just six weeks.
If you’re chasing tone
How to lose fat and gain muscle simultaneously, or around the same time, is among the fitness world’s greatest quandaries. Garard advises adding kettlebells to your HIIT workout.
“It has a good fat burning effect as well because your heart rate’s up as well, and the fact that you’re using your whole body in all those movements as well,” Garard says. The ideal kettlebell range is 12 to 16 kilograms. Factor them into eight 20-second intervals and see how many swings you can do in each round (think 20 to 30). By round five or six you should be struggling.
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