The term ‘volume’ is used to describe how much 'work' you do.
We can measure volume in terms of volume per session, volume per week, and even in greater chunks, such as volume per training cycle. Typically though, it’s discussed more on a session-by-session basis, or in terms of volume per week.
Volume is the amount of weight lifted, multiplied by the number of reps you do.
So if you did 5 sets of 5 squats at 100kg (220 lbs) that would be a total volume of 2,500kg (5500 lbs.)
Sometimes you’ll see volume talked about in terms of number of sets, or number of exercises, but the most accurate data we can refer to is volume in terms of the actual total weight lifted.
Why Measure Volume?
Volume is a key driver in both getting stronger and building muscle.
To get bigger, you need four things - muscle damage, metabolic stress, mechanical tension, and volume. (1)
For increasing strength, volume plays an equally important role. Muscle damage, metabolic stress and mechanical tension aren’t quite as critical when it comes to developing maximum strength, as things like skill acquisition and development of the nervous system come into play more, but volume is still critical.
If you’re not gradually increasing your volume throughout your training career, it’s highly likely you won’t be progressing anywhere near the speed you should be, and may not even be improving (building muscle/ strength etc) at all.
Volume for Muscle Growth
As we’ve already established, you do need some muscle breakdown to elicit hypertrophy.
That means you can’t just do tonnes of easy sets, chalk up a very high volume workout with, say 20 sets of 10 reps at 50% of your 1-rep max, and expect to grow in a catastrophic fashion (unfortunately).
This type of training, while high-volume, would be very unlikely to cause the kind of muscle breakdown, metabolic stress, or be at a high enough intensity to build new muscle tissue.
However, provided we have those other factors - mechanical tension, metabolic stress, and muscle damage - volume becomes the key driver in growth.
A 2019 study from Schoenfeld, Krieger, Contreras et. al concluded that -
“[...] muscle hypertrophy follows a dose-response relationship, with increasingly greater gains achieved with higher training volumes.” (2)
Basically meaning the more volume you do, the greater your gains are likely to be.
Various studies have shown that multiple sets are superior to single working sets of an exercise, (3), while some have even shown that pushing volume as high as 32 sets of an exercise per week can yield effective results. (4)
Volume for Strength
The research for strength training seems a little more varied.
Some studies for example show preferential results in moderate to high volume routines over low volume ones, (5, 6) whereas others show that greater volume doesn’t necessarily lead to greater strength increases.
A 2018 study from the Medicine and Science in Sport and Exercise Journal concluded that -
“Marked increases in strength and endurance can be attained by resistance-trained individuals with just three 13-min weekly sessions over an 8-wk period, and these gains are similar to that achieved with a substantially greater time commitment.” (7)
That said, an advanced lifter will likely have a fairly high-volume routine anyway, as even if they were just doing, say, 3 sets of 3 reps on squats, their working weight would be relatively very high, and they’d need to do plenty of heavy warm-up sets to even get to their working sets, which all contribute to their total volume accumulation.
Volume for Fat Loss
There’s no real ‘best’ volume to use for fat loss. The main factor when it comes to losing body fat is being in a calorie deficit. Extra weight training volume is highly unlikely going to burn enough extra calories to make a significant difference to the rate at which you lose weight.
That said, it makes sense that in order to maintain muscle mass and strength, you’re going to want to at least try to maintain the same volume you were doing in your strength/ hypertrophy/ maintenance phase, when you’re in a calorie deficit. If you are in the position to continue overloading & increase your training volume despite being in an energy deficit, you should find you're able to increase your chances of maintaining more muscle mass.
High? Low? Or Somewhere in Between?
Volume is likely to vary from person to person.
A more experienced lifter will very likely need more volume to build size and strength, whereas a newer lifter would be able to get away with a lot less.
One thing we can say with a fair amount of certainty, however, is that everybody needs to be training somewhere at or near their Maximum Recoverable Volume (MRV).
MRV is a term coined by exercise scientist Dr. Mike Israetel, and is defined as the highest amount of training you can do, but still recover from, to perform that same workout the following time, but no more than that.
I.e. If you perform a leg workout that contains 5 sets of back squats, 3 sets of leg presses, 2 sets each of leg curls and stiff-legged deadlifts, and 4 sets of calves, if you get moderately sore afterward, and feel able to progress your weights or reps most (if not all) training weeks, that’s likely your MRV.
If, however, you find you have virtually no after-effects, and struggle to increase your strength due to lack of stimulus, it may be under your MRV.
Similarly, if you feel incredibly sore for 3 to 4 days, can’t get your energy up for your next leg workout, resort to using poor form, or constantly feel demotivated, there's a good chance you're overshooting your MRV.
Some self-experimentation is needed to discover what your MRV is, but the way MyPhysique is set up, you'll end up making your way through the sort of volume that will keep you around your MRV in a consistent fashion. The TeamBuildr app will let you track the weights you're lifting, and from there you'll be able to better manage the loads you're using as you establish the effect it has on you from a recovery perspective.
The key thing to remember is, no matter what volume you’re getting through, you want to be looking to increase it over time.
This may not happen every single session, especially if you’re in a fat loss phase. In fact, it probably won’t increase every session, unless you’re new to training. But by and large, month-to-month, or on a training block to training block basis, you should be looking to increase volume in some fashion, either by increasing weight, reps, sets, or adding more exercises.
If you're already following a MyPhysique program you won't even need to worry about this, because you'll be accumulating an increasing amount of volume on a training block by training block basis simply by following the program perfectly.