How many sessions a week are needed to build muscle?

By Kalorya · July 22, 2026 · 7 min read

Athlète à l'entraînement en salle de musculation

‘Train each muscle twice a week’: that’s the advice you see everywhere. Studies suggest something a little more nuanced — and a little more liberating. What determines your muscle gain isn’t the number of sessions, but the total volume over the week. Frequency is simply a way of spreading that out.

Where does the advice to ‘twice a week’ come from?

This finding comes from a 2016 meta-analysis which compared training frequencies: training a muscle twice a week yielded better results in terms of hypertrophy than training it just once. The difference is real and statistically significant.

Effect on hypertrophy depending on frequency(the longer the bar, the greater the measured muscle gain)

2016 meta-analysis on training frequency and hypertrophy (p = 0.002).

However, there is one crucial piece of information missing from this graph: in these studies, the groups that trained more often also did more sets in total. So the comparison was not simply between two frequencies — it was between two training volumes.

What happens when you equalise the volume

This is where the research gets interesting. Several studies have repeated the comparison, giving everyone the same number of sets per week, but distributed differently. The result is consistent:

Work	Question asked	Earnings on a like-for-like basis
2019 meta-analysis : ‘How many times a week?’	Hypertrophy	No significant difference between frequencies
2018 Meta-analysis	Strength	The advantage of high frequencies is lost
2019 Review	Hypertrophy	1 time a week ≈ 2 to 3 times a week
2019 Study (trained men)	Muscle strength and thickness	1× vs 2× a week: no difference

The key takeaway

Frequency doesn’t have any magical effect in itself. If it ‘works’, it’s because it allows you to fit in more sessions during the week without having to do endless workouts. Given the same total volume, training 1, 2 or 3 times a week yields comparable results: just choose whatever fits into your schedule.

It’s the volume that really counts

Whilst frequency is neutral, volume is not. A 2019 study of trained men compared 1, 3 and 5 sets per exercise, three times a week for 8 weeks: strength increased equally across all three groups, but hypertrophy followed a dose-response relationship — more sets, more muscle (arms and thighs).

A 2022 study takes this a step further: tailoring training volume to each individual’s history resulted in greater muscle growth (+1.08 cm² in quadriceps cross-sectional area) than applying the same volume to everyone.

So, in practical terms, how many sessions?

The most comprehensive review is a network meta-analysis from 2023, which compared combinations of load × sets × frequency in healthy adults. It does not provide the same answer depending on your objective:

Your objective	Load	Series	Frequency
Maximum force	Heavy (> 80% of 1RM)	Several series	3 sessions a week
Muscle gain	Various loads, including heavy ones	Several series	2 sessions per week

In other words: two sessions a week per muscle group is still an excellent starting point for building muscle — not because the number 2 is some sort of magic number, but because it’s a convenient way of spreading the workload sufficiently.

What if I can only train once a week?

Good news: one session a week is enough to maintain your fitness levels. In professional footballers, one strength training session a week maintained strength and sprint performance over 12 weeks — whereas one session every two weeks led to a decline in both.

What not to do

Stop completely. In a 1988 study, participants who stopped training altogether lost 68 per cent of the strength gains they had just made. A short session is infinitely better than none at all.

In summary

Question	What the studies say
Does the frequency affect the results?	No, for the same weekly volume
So what really matters?	Total volume per week (dose-response relationship)
How many sessions should you aim for?	Twice a week per muscle group for muscle development, three times a week for maximum strength
Just one session a week?	Enough to maintain your current level, but less effective for making progress
What if I stop?	Up to 68 per cent of strength gains lost

The easiest way to maintain a consistent training volume is to have a written programme. If you have a coach on Kalorya, they can put one together for you and monitor your sessions.

View my programmes

Finally, remember that training is only half the battle: without sufficient protein intake, that volume won’t turn into muscle. We discuss this in our article on the most scientifically proven supplements for building muscle mass.

All the figures in this article are taken from the studies listed below, summarised on the basis of their abstracts alone. This is for information purposes only and is not a substitute for professional advice.