You Only Need 1 Dumbbell and 90 Minutes a Week to Build Muscle at Home This Summer

I'm not a fair-weather trainee. I like to train outside all year round.

That being said, I don't hold it against anyone if they just want to make the most of the summer and take their workouts outdoors. The gym can get pretty crowded at this time of year, and if you're unlucky enough to be in a facility that doesn't have air con, it can be absolutely heinous.

But if you don't have the budget for a full home gym kit-out, you can feel as though you're forced to stay in there if you want to make any real gains. However, that isn't the case.

You can take your physique a long way using that one dumbbell that's moved from house to house with you, unused, for the last 15 years. Or even just by picking up a cheap adjustable dumbbell (or an expensive one, if you want to invest).

This three-day plan is designed so you can take your one dumbbell out into the garden or your local park, absolutely blitz yourself with simple, trackable, full-body conditioning sessions that last just 30 minutes each… and then get on with your day.

Keep your protein high, get your calories in place to fuel those sessions, and track all of your workouts – rounds achieved, reps accrued – aiming to see progression in these 'scores' across the weeks. Progress in the mirror won't be far behind.

Most of all, enjoy the extra time you score back by not having to commute to and from the gym – and the extra cognitive bandwidth that comes from being able to train in nothing but your shortest shorts in the garden.

Follow the sessions sequentially, letting rest days fall where they may, and repeat the plan for 4-6 weeks, aiming for improvements each week.

Enjoy.

Each of the three sessions follows the same simple format: follow your own 10-minute warm-up before jumping into the 20-minute AMRAP (as many rounds/reps as possible) built around four movements – a push, a pull, a lower-body exercise and a core movement. That means every workout trains your entire body, while the three-session structure ensures each major muscle group gets hit multiple times across the week, ideal for muscle-growth.

Push each movement close to failure, especially in the second half of each AMRAP, with a challenging dumbbell (notes on dumbbell weight below). You’ll rack up just 90 minutes of training access the week, but you’ll get a dose of everything you need to build muscle, strength and conditioning.

Warm-up as necessary, followed by 20 minute AMRAP

Single arm shoulder press (on each side) x 5 reps

Renegade row (on each side) x 10 reps

Goblet squat (heels elevated) x 20 reps

Laying leg raise (hanging if you can) x 25 reps

Warm-up as necessary, followed by 20 minute AMRAP

Alternating dumbbell snatch x 10 reps

Push-up x 15 reps

Alternating goblet reverse lunge x 20 reps

Plank shoulder tap x 30 reps

Warm-up as necessary, followed by 20 minute AMRAP

Dumbbell clean and press (from floor each rep. Perform on both sides) x 5 reps

Dumbbell clean (from floor each rep. Perform on both sides) x 10 reps

Alternating goblet forward lunge x 20 reps

Sit-ups x 25 reps

If you're picking weights, or you have a selection available, use a dumbbell that challenges you on every movement in each AMRAP. You should be struggling to hit the prescribed reps and, on some movements, possibly even have to break the sets up to get them done.

That way, you're working close to failure and you'll get the correct stimulus to build muscle.

If you're buying a dumbbell (or dumbbells) for the first time, a good rule of thumb, if you're going to use the same bell for all of your lifts, is to pick a weight that you can only strict press overhead around five times.

With your overhead press acting as the limiting movement, you'll be in the sweet spot where you're still able to train your shoulders heavily while also getting plenty of stimulus from higher-rep work for your stronger muscle groups, such as your quads, hamstrings and back.

If you have a weight already and it’s a little on the light side, up the reps to seek out the same stimulus. Too heavy? Drop the reps. Either way, track those reps and aim to seek out incremental improvements each session.

If there’s one thing Kori Sampson knows, it’s how to optimise your body composition for performance. To tap into his knowledge as an elite athlete and coach, we asked him to create a 4-week plan to help you move faster, recover quicker and keep pushing when the fatigue sets in – all while improving your muscle-to-fat ratio.

Ready to build muscle, burn fat and come out the other side looking, feeling and performing better? Click here to get 14 days of free access to the plan via the Men’s Health app.