Read time: 4 minutes

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It’s arguably the most critical question with exercise:

How much do you need to get a benefit?

That and: is more exercise always “better”?

Most exercise guidelines advocate for the “optimum” dose (or close to) for health benefits.

But there’s a good argument to focus instead on achieving at least the minimum effective dose of exercise.

After all, most people do little to no activity, let alone anything near “optimum”.

A recent study has unlocked new insights into how much resistance training is needed to improve muscle size or strength.

And you might be surprised how little this is.

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The smallest amount of resistance training needed for muscle gains

Let’s get straight to the point (more of the “nitty gritty” detail later).

The study in question was a meta-analysis of the dose-response relationship between weekly set volume and training frequency on muscle size and strength.

The analysis found the minimum effective dose of resistance training was:

• 4 weekly sets (per muscle group) for muscle growth
• And just 1 weekly set for strength

This was the smallest amount of training that could produce detectable changes in muscle size or strength.

So in other words, between 1 and 4 resistance training sets per muscle group per week was enough for measurable gains in strength or muscle mass.

A pretty achievable dose for most people I would say.

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So, did more training mean extra benefits?

In short, yes.

The study found both muscle size and strength tended to increase with more volume (or weekly sets per muscle groups) - although in a non-linear fashion.

This means the extra benefits became less and less with higher “doses”.

These “diminishing returns” were also greater for strength than for muscle mass:

So, more volume had a greater impact on muscle growth than strength.

What’s also neat was the study estimated how many extra sets (beyond the lowest effect dose) would produce further gains in strength and muscle size:

Again it’s clear more volume had a greater impact on muscle size, with up to 30-42 sets per week still producing extra benefits.

But more volume was less important for strength, with 5 sets per week no longer having a clear benefit beyond 3-4 sets.

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The next question: did training more often matter?

Turns out it depends.

To be clear, we’re talking about if training more frequently provides more benefit for a given exercise dose.

In other words, is it better to spread a given exercise amount over more sessions during the week?

The analysis found the answer differed for muscle growth and strength.

Higher training frequencies had little impact on muscle growth, but meaningful benefits for strength (though again with diminishing returns):

This means training a muscle group or movement pattern more often during the week might have extra benefits for strength, but not muscle mass.

To gain muscle, the most important thing seems to be the total volume across the week.

But for strength, how often a particular muscle or movement in trained is key.

This reflects the idea repetitive practice and motor learning are important for strength gain, but these are less critical for building muscle.

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As promised, here’s the nitty gritty detail (for those interested)

So how exactly did the authors of the study arrive at these numbers?

The analysis included 67 resistance training studies lasting a minimum of 4 weeks in participants aged 70 or younger (mean age = 25 years).

Each study compared at least two groups that differed in set volume and/or frequency while controlling for factors like load and proximity to failure.

On average, the interventions were:

• 10 weeks long
• With 2 sessions per week
• 8-13 weekly sets per muscle group
• And 10-11 reps per set

This study builds on previous attempts to capture the dose-response relationship in resistance training by:

• Treating resistance training dose as a continuous variable, rather than categorising weekly sets (e.g., comparing 10-20 vs. 21-30 sets)
• And by weighting the contribution of "indirect" sets that might have a secondary influence on strength or muscle hypertrophy outcomes as half a set

Overall it’s the most comprehensive analysis of the dose-response for resistance training effects on muscle size and strength.

And the findings have some really interesting implications for practice.

Putting the findings into practice

The main take-homes from this study are:

• Small doses of resistance training (just 1-4 sets per week) can improve muscle mass or strength
• More volume (weekly sets) benefits muscle hypertrophy more than strength
• Higher training frequencies are more important for strength

These figures provide a baseline target for those looking to get started with resistance training - or even just to maintain their muscle size or strength.

From there, the strategy could differ based on the main training focus:

• To build muscle, it’s more important to do more volume (sets) across the week, regardless of how often you train
• To gain strength, it’s less important to do more sets across the week, and more critical to train more often

So depending on your goals, either finding ways to build more volume (sets) into your routine across the week (for muscle growth), or training key movements or muscle groups more often (for strength), may be more important.

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You don’t need a lot to benefit from resistance training

The key message here is even small doses of resistance training have benefits.

For many, this “minimum effective dose” may be more achievable than anything close to optimum.

After getting started (and being consistent) with at least the minimum dose, there’s always scope to do things “better” later.

But let’s not forget the greatest impact always comes when going from nothing to something.

And these new findings show just how little that can be.

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As always, it’s great to have you here!

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Until next week,

Jackson

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IMPORTANT:

The information contained herein is of general nature only and does not constitute personal advice. You should not act on any information without considering your personal needs, circumstances, and objectives. Any exercise program may result in injury. We recommend you obtain advice specific to your circumstances from an appropriate health professional before starting any exercise program.