20 minutes, seven moves, and one kettlebell to boost your metabolism and build muscle all over

Exercising at the gym can be a great way to use all the machines and weights you don't have at home. This is useful, but it's not the only way to build muscle. In fact, you need just a single weight with this 20-minute full-body routine. 

The best kettlebells are ideal for training at home as you can use it for a range of exercises that target the entire body, strengthen your core, and raise your heart rate Plus, it's easy to store and won't take up lots of room. 

This straightforward kettlebell workout created by Stef Williams, a personal trainer and founder of the fitness app WeGLOW, is only seven moves, but it targets all of the major muscle groups and it's great for building strength.

Williams uses two different kettlebells, with weights of 26lbs and 35lbs. This is because some of the exercises are more intense than others. You might choose a heavier weight for the kettlebell swings, while dropping the load for bent over rows. 

The aim is to complete each exercise for 45 seconds, followed by 15 seconds of rest, and to repeat the seven-move circuit twice. This will take 20 minutes, but if you have more time you could attempt a few more rounds.

It's crucial to use the correct technique when working out with weights to get the most from your training and avoid injury. Fortunately, you can use William's demonstrations to perfect your form before you start. 

Watch Stef Williams' kettlebell seven-move workout

You'll be moving for 45 seconds, but you can choose your own pace. If you're more focussed on muscle growth than endurance, opt for a heavier weight and move slowly but intentionally through exercise.

This is a great workout to add to your weekly routine as a full-body session. Or, you can do it as a finisher to another strength session, to burn out your muscles and get your heart-rate up.

It's effective, in part, thanks to the style of exercise; high-intensity resistance training (HIRT), where the aim is to work your muscles hard in short bursts with minimal rest. The lack of breaks also means you sustain a high heart rate. 

This burns energy during your session, but causes longer-term changes, like boost your metabolism — the amount of energy you burn throughout the day — for a muscle-building, fat-burning workout in just 20 minutes. 

Don't forget to refuel with enough protein after working out. This will help your muscles recover and promote muscle growth. Try the best protein powders for weight loss and try a stretching routine for optimal recovery.