Are avocados healthy?

Your lunch hour workout is anything but. Getting to the gym, changing, showering after and heading back all eat into your time on the gym floor, leaving you  a 30-minute window to build up a sweat. It's almost not worth leaving your desk, right?

Not so, according to strength & nutrition coach Brett Durney. His techniques will build quality muscle in a limited window. Follow this simple four-stage programme to optimise your hour, then tackle the full body blitz workout for a quick session that will leave you reeling. It’s time to embrace the brutal efficiency of a true power hour.

Stage 1: Prepare

Be quick off the line when the lunchtime start gun fires by prepping everything the night before. That includes your gym bag – so you don't leave your shorts under your desk – and your post-workout protein shake and lunch. Having it all pre-packaged means less time queuing in Boots for a meal deal, and more time earning that chicken triple sandwich.

Stage 2: Warm-up

A warm-up seems like wasted minutes when you're short on time. You'll have to time to muse on that decision later, when an injury keeps you out of the gym. “Your muscles are like playdough,” says Durney. “When they're cold they’ll snap, but warm them up and they’ll stretch smoothly and safely.” Opt for a dynamic warm-up. Grab a med ball and squat whilst raising the ball to the sky; repeat whilst lunging. Next, hit the floor: planks with side touches and mountain climber reaches will prime your whole body and get your muscles firing. So you can crack on with playtime.

Stage 3: Showtime

This is no time for challenging your one rep max. These training methods take your muscles to full fatigue quickly, if you're strict with your rest times and stick to the prescribed movement tempos. The clock's ticking.

Tri-sets: use three exercises which target the same muscle group, performing each one after the other with no more than 10 seconds change-over. Your rest period will depend on your goal: someone trying to grow lean muscle mass will typically wait 1-2 minutes between moves.

Giant sets: take a tri-set and make it harder. Using four exercises of the same muscle group buils muscle mass and torches body fat at the same time, sending you back to the office with a lean pump.

Pre-exhaust superset: an isolation exercise exhausts the muscle group you’re working, before a  compound move performed immediately after takes it to breaking point. More gains, less time.

Post-exhaust superset: reversing the pre-exhaust, you’ll start with a big, compound movement that works your chosen muscle group, then move to an isolating exercise that gets it screaming. Try bench press to dumbbell flyes to overload every inch of your pecs. Just try not to look too exhausted at your desk.

Tabata training: Follow 20 seconds at 100% effort with 10 seconds of rest for eight sets. Use total body exercises, like burpees, to fatigue muscles and burn fat simultaneously.

Stage 4: Recovery

After a burn-out like that, it’s time to take action. Neck that shake you prepared before getting back to the office, ASAP. Now for your warmdown. Stretching at your desk might not be the most discreet, but it’ll save you precious time. Calf stretches can be done sat down, as can a lat stretch. Hold your desk with both hands and push your chair backwards, keeping a straight back. Just don't tilt it, as your primary school teacher would tell you.