Nine moves, 30 minutes, and two dumbbells to build stronger arms and boost your metabolism

High-intensity workouts are an efficient way to train and boost your metabolism, but blending it strength-based exercises can be a great way to improve your endurance, build muscle, and burn fat. 

To take part, you'll need two dumbbells (and a yoga mat if you want to make your workout area a bit more comfortable). You'll want a set that's heavy enough to challenge you through a round of overhead extensions without affecting your form. 

If you want to move between weights for different movements, it's worth investing in a pair of the best adjustable dumbbells. These combine several weights into one, so you can increase the load as you get stronger using the progressive overload technique. 

This routine was created by personal trainer Sydney Cummings Houdyshell and primarily targets your triceps and biceps. You'll do three rounds of each move as a circuit, working for 45 seconds followed by a 15-second rest between exercises. 

To get the most from your training, it's important to make sure you do each move with the correct form. Fortunately, you can follow along with Houdyshell's demonstrations to perfect your technique as you go. 

Watch Sydney Cummings Houdyshell's 30-minute arm workout

This routine blends high-intensity interval training (HIIT) with strength-based moves to create a high-intensity resistance training (HIRT) workout. It's an intense routine that includes upper body moves such skull crushers, tricep dips and hammer curls. 

HIIT workouts for fat loss are a great way to boost your metabolism — the amount of energy your burns throughout the day. HIIT primarily targets your cardiovascular fitness, keeping the pace up to raise your heart rate. 

The aim is to do short bursts of activity followed by a brief rest. Houdyshell's workout adds muscle-building moves into the mix, helping increase your heart rate, boost your metabolism, and develop strength all over your body. 

But by adding the strength element, your muscles may feel a little sore the next day. This is known as delayed onset muscle soreness (DOMS), and while painful, it is completely normal and caused by tiny tears in your muscle fibers. 

Your body uses protein to repair these tears, which is why many people blend up a post-workout smoothie to increase their intake. If you're after a powder to help you develop lean muscle, it's worth taking a look at the best protein powders for weight loss.