Build Muscle In Just Fifteen Minutes With This Complex Training Workout

Bench press
(Image credit: Glen Burrows)

The complex training workout below involves doing a heavy weight exercise followed by an explosive move with a lighter weight. This works your muscles harder and to exhaustion in much less time, meaning you can get a worthwhile worout in just 15 minutes.

Complex training is one of many time-saving training philosophies. Try these clock-beating workout tips you can apply to any exercise session.

Streamline your warm-up

If possible, jog to the gym as a warm-up, then go straight into the weights room and start your workout. If it’s not possible, do the first upper- and lower-body exercises in your workout back to back without any weights. This both warms you up and primes your nervous system to fire your muscles in the correct sequence once you add weight to the move.

Don’t get isolated

"If you’ve only got 15 minutes, don’t bother trying to isolate individual muscles – aim to hit several at once and preferably the whole body," says Darren Roberts of Peak Performance Training. Do standing exercises such as a lunge to press that require moving more than one joint to perform and allow you to lift large weights.

Never queue

If the bench press is busy, move on and adapt the exercise to the available equipment. A gym ball and dumbbells can replace a bench and barbell and can offer extra benefits – in this case an additional core workout.

Target movements, not muscles

Switching your focus away from individual muscle groups or body parts and towards movements such as ‘pull’ or ‘push’ frees up your workout so you can hit a lot of muscles at once. Use multi-joint and multi-directional exercises such as the woodchop. Team this move with vertical movement exercises (such as pull-ups) and horizontal ones (such as the bench press).

Sacrifice a cardio session

A 15-minute HIIT weights workout can improve your endurance performance. A study from Finland’s Jyväskylä University showed that athletes who replaced 20% of their cardio work with an explosive strength training session recorded a 3% faster average speed when running.

Pump up the volume

Do five reps on the bench press with as much weight as you can handle, then strip the weight to your 10-rep max and do another set, and then strip some more weight off and aim for 15 reps. This is known as volume training.

Complex Training Workout

Complex training allows you to generate more force in less time, reducing your workout time but increasing its effect. 

You pair a heavy weights exercise with an explosive move. "The first exercise gets your body used to recruiting a large number of muscle fibres for the second," says Allan Collins, technical director of Juice Performance Training. Do the first heavier move, then go straight on to the lighter second. Because the first forces your body to make more muscle fibres available, you'll work your body harder than you would if you just did the second exercise as a stand-alone move.

Barbell squat


(Image credit: Unknown)

Reps 12

Keep your knees in line with your feet and your back neutral.

Jump squat


(Image credit: Unknown)

Reps: 12

Use a light weight and push up explosively.

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Nick Hutchings worked for Men’s Fitness UK, which predated, and then shared a website with, Coach. Nick worked as digital editor from 2008 to 2011, head of content until 2014, and finally editor-in-chief until 2015.