Want to build stronger legs? You only need 40 minutes and a set of dumbbells

If you're tight on time, you may prioritize upper-body workouts, but it's just as essential to build lower-body muscle and improve your stability. That's where this 40-minute dumbbell routine can help, focusing on your legs and core to develop practical lower body muscle.

You don't need much equipment if you're working at home either, just a set of the best adjustable dumbbells. These weights combine several dumbbells in one, so you can use progressive overload to gradually increase the load as you get stronger. 

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Most gyms have fixed-load dumbbells available, which means you'll need to select a single set of weights before you start. Wondering what dumbbell weight you should use? The key is to find a load that will challenge your muscles but won't affect your form. 

Once your weights are at the ready, then you're primed to started fitness trainer DanielPT's lower body routine.

There are eight 'giant' sets of five moves; four focused on your lower body, and one to target your core. You'll do each move for 40 seconds, take a 15-second rest, then start on the next exercise. There's also a 30-second water break between sets, so keep one of the best water bottles for gym workouts nearby.

It's crucial to focus on your form to get the most from this session and protect yourself from injury. DanielPT demonstrates each exercise, so you can follow along and practice the technique as you go. It's also worth refreshing your knowledge of how to deadlift with dumbbells before you start.

Watch DanielPT's 40-minute leg workout

It's not an especially short routine — you can find plenty of muscle-building workouts that take about 20 minutes — but it's still a time-efficient way to train. The moves don't target one area in isolation like a bicep curl would. Instead, these compound exercises work multiple muscles across your body simultaneously.

So while the focus is on your lower body, you'll still be training your arms, shoulders, and core. This is coupled with a training style designed to get results quickly: high-intensity resistance training (HIRT). The aim is to exercise in short bursts with minimal rest.

This helps pack a lot into the routine, but there are other benefits. Exercising intensely raises your heart rate, increasing the energy you burn during the workout compared to an equivalent steady-paced alternative.

Sustaining an elevated heart rate also boosts your metabolism, the amount of energy your burn at rest, for all-day fat-burning results. This type of exercise is similar to a high-intensity HIIT workout for fat loss but with a focus on strength-building moves rather than cardio.

When you exercise, it causes tiny tears in your muscles to appear – your body needs protein to repair this damage. You can keep your protein levels topped up with the best protein powders for weight loss and even turn them into a smooth post-workout recovery drink with one of the best blenders for protein shakes.