An excellent paper by Schoenfeld et al. was recently released covering the current training recommendations to maximise muscle gains. I have summarised the main points. The full paper is free to download.
Training load / Repetition ranges
Similar muscle hypertrophy can be achieved using light and heavy loads when total sets/volume are equated. There appear to be no differences in muscle gains when training within the 5-25 rep range. However, if someone wants to gain strength whilst gaining muscle, heavy loading is generally more advantageous than lighter loads. There are likely loads that are too light (possibly about 20% of 1RM / 35 reps +), which might be sub-optimal for gaining muscle. Evidence is mixed if light loads more target type I fibres and heavier loading targets type II fibres. It is recommended to use a variety of repetitions falling within the 5-25 range, either within a training session or across different training blocks.
Volume is suggested to be one of the main drivers for gaining muscle. An easy way to calculate volume is by counting the number of work sets completed when the reps completed fall within the 6-20 rep range. Although higher training volumes generally result in greater muscle gains, there is likely an upper limit whereby doing too many sets causes muscle gains to plateau or regress. The upper limit of training volume has not been found, and it may depend on the individual and the muscle groups being trained.
The approx. minimum sets per muscle group per week to optimise muscle gains is suggested to be around 10 sets. However, some people might be able to grow muscle from lower volumes optimally. When increasing training volume, it is suggested to increase by 20% from habitual volume. When reaching the end of the training block (eg 4-8 weeks block), re-adjustments to training volume could be made if needed. Running specialisation blocks where higher volumes are performed on specific muscle groups with volume being reduced on other muscles may be effective.
This is referred to the number of times a muscle group is trained per week. When training volume is equated, training a muscle group once or multi times per week appears to be similar for gaining muscle if the total weekly sets for the muscle group is <10 sets. If performing >10 sets in a week for the same muscle group, splitting the volume over two or more training sessions within the week may be ideal. Doing too many sets for a muscle group in a single session might result in a blunting effect whereby additional sets might not be stimulating the muscle to grow any further and may be classified as ‘wasted sets’.
Rest between sets
There does not appear to be a benefit of having a short rest break (e.g. <1min) compared to longer rests (>2min) for muscle hypertrophy. Short rests may be detrimental as fewer repetitions (less overall volume) may be performed due to fatigue. It is recommended to take as much rest as you need until you feel recovered to perform the next set with minimal fatigue from the previous set. Rest length may differ between exercises, muscle groups and the individual. Multi-joint compound exercises may need a minimum of 2 minutes rest, where shorter rests such as 60-90 seconds may be adequate with isolation and machine-based exercises.
It is suggested to use a variety of different exercises which target the same muscle group, using different positions and angles to stimulate all parts of the muscle. A combination of compound and isolation exercises is likely ideal. It is not clear how many weeks an exercise should be used before rotating. However, it is likely beneficial to keep the same exercises for a few weeks before rotating to something different and not changing exercises weekly. Compound free weight movements, which require more complex technique, should probably remain in the program to maintain motor pattern skill. Less complex movements like isolation and machine-based exercises can likely be rotated more frequently.
Proximity to failure
If training to failure promotes more significant gains compared to not training to failure is not entirely clear. It seems that failure training in beginners shows no advantage compared to non-failure training (I would discourage going to failure in beginners anyway as technique breakdown is likely to occur). Trained individuals can make sufficient progress not training to failure. However, failure training could be beneficial for trained individuals and could be implemented on the last set of isolation and machine type exercises to minimise excessive fatigue. It is not recommended to take every set to failure as this may lead to overreaching. Failure training can be used conservatively or in a periodised fashion. However, going to failure is not required for gaining muscle, and a greater portion of training should likely not be to failure.
Utilise a broad range of repetitions between 5-20 reps. That’s not to say hypertrophy would not occur outside this range. But this will likely give you the best payoff for time and effort investment.
A minimum of 10 sets per muscle group per week seems like a good starting point. Some people may be able to make good progress on less than this, such as beginners. Others may need a higher weekly set minimum, particularly if they are more trained.
If doing <10 sets on a muscle group per week, training frequency may not be important. If doing >10 sets on a muscle group per week, it may be ideal to spread training volume over multiple days.
Take as much rest as you need (obviously up to a point) between sets so there is minimum fatigue lingering around from the previous set, which may affect the performance on the upcoming set. A minimum of 2 minutes rest for multi-joint compound movements and a minimum of 1 minute rest for single-joint isolation type exercises is recommended. Of course, these minimum times would differ depending on the individual.
Using a variety of exercises that target the same muscle group is recommended to stimulate the entire muscle. Have some base compound lifts that remain in your program most of the time; isolation exercises can be rotated more often.
Training to failure is not required for muscle hypertrophy but could be used conservatively. If going to use failure training, it is suggested to do this on the final set of an exercise and saved for isolation and machine-based exercises. A greater portion of sets should not be taken to failure.
Remember – These are general recommendations and typically based from population averages. There are always going to be outliers and individuals who respond to different protocols. The above should only serve as a guide and not hard rules.
Schoenfeld, B., Fisher, J., Grgic, J., Haun, C., Helms, E., Phillips, S., Steele, J., & Vigotsky, A. (2021). Resistance Training Recommendations to Maximize Muscle Hypertrophy in an Athletic Population: Position Stand of the IUSCA. International Journal of Strength and Conditioning, 1(1). https://doi.org/10.47206/ijsc.v1i1.81