The 'one-set rule' is a simple way to build muscle and save hours in the gym - here's how it works

We might all have different preferences in the gym, but everyone shares one experience - some days, the motivation just isn't there. The good news is, a new study suggests the one-set rule could be the answer to boosting strength and building muscle in less time.

The research found that doing a routine of one-set exercises in a strength training workout for 30 minutes, twice a week, can build muscle. That's right - doing just one round of exercises, instead of the standard three or four, can help boost muscle mass and may, by extension, help ward off various negative health conditions that come with age.

The findings were published recently in the Journal of Medicine and Science in Sport and Exercise, with experts from the American College of Sports Medicine looking at how single-set training influences muscle growth, strength, endurance, and power.

Exercises in the training session included:

• Lat pulldown
• Seated cable row
• Machine shoulder press
• Machine chest press
• Cable tricep pushdown
• Dumbbell bicep curl
• Plate-loaded leg press
• Machine leg extension

Together, these make up some of the best back exercises, upper-body, glute, and quadricep exercises.

All of the participants performed the nine exercises twice a week for eight weeks, but were divided into two groups. The first group trained towards failure (until they couldn't physically do any more repetitions) and the second trained with less intensity, leaving two repetitions in reserve.

All of the participants had done weight training before, so this isn't the recommended strength training workout for beginners.

Researchers measured muscle thickness, strength, power, and endurance of all participants before and after the study, discovering that both groups saw positive results from single-set training.

However, the best results were seen in those who pushed to the limit, training to failure. The difference was small, but the group saw larger gains in muscle mass.

For those going through menopause, this is particularly significant as muscle mass tends to decline during this life stage without proper exercise and nutrition intervention.

The study's authors made the same conclusion, saying that one-set routines can be a time-efficient strategy for promoting muscular adaptations in resistance-trained individuals.

"Training to failure in single-set routines may modestly enhance some measures of muscle hypertrophy and power, but not strength or local muscle endurance," they said.

So, if you're training on holiday, in a busy work period, or you're short on time for any reason, ditching your regular weights routine in favour of a hard single-set workout could be the answer.

What is training to failure?

The phrase ‘training to failure’ can sound quite intimidating, but it’s an effective weight-lifting technique. It involves lifting heavy weights until you can’t go on without compromising on your form. When you can’t perform that last rep, it’s called “technical failure,” according to the American National Academy of Sports Medicine (NASM).

The closer you get to failure, the more your muscles grow, a recent Sports Medicine review found. This is why the other group still made progress, despite leaving a few repetitions in the tank.

You’ll know if you’ve reached this point because it'll be a real struggle (or impossible) to do another repetition. You’ll either need to put the weight down or need someone to take it off you, which is why it's better to aim for this on your final set of each exercise. Or, if you're following this study, on the final repetition of your single-set workout.