Reading time: ~5-6 minutes
Takeaways for the effects of frequency on strength gains:
- Indendently of volume, higher frequencies seem to benefit strength gains.
- High frequency is particularly beneficial for women, upper body training, compound lifts and young populations.
- The difference between higher and lower frequencies’ rates of strength gains seems to be around ~20% when volume is matched. In the real world, the effects are probably higher, as higher frequencies are usually permissive of higher volumes.
- The marginal benefits of increased frequency, when volume is matched, don’t seem to decrease much, even all the way up to 4+ times a week.
Training frequency might be one of the most controversial topics in strength training.
Some people advocate low training frequencies, claiming that you’ll overtrain if you train a bodypart more frequently than once a week. They’ll then give you examples of various bodybuilders who got big training every muscle group only once a week, underlining that, once you get to a certain size, you can’t train as often as you could previously while still recovering.
In response, the high frequency crowd replies that, well, training only elevates MPS (Muscle Protein Synthesis) for a few days at most before returning to baseline, so, obviously, to grow the most and get the strongest, you’d need to train pretty darn frequently, particularly if you’re advanced.
Let’s take a look at the evidence in favour of these claims. This will be a two-part series. The first article covers the effect of frequency on strength gains, while the second will cover hypertrophy.
Low vs High Frequency for Strength Gain
Luckily for me, there’s been a lot of recent research into training frequency. I’ll be taking a look at the results from the two most recent meta-analyses on training frequency and strength.
Effect of Resistance Training Frequency on Gains in Muscular Strength: A Systematic Review and Meta-Analysis by Grgic et al. (2018)
- When studies matched volume between groups, there was no significant effect of training frequency on strength gains.
- There was, however, a beneficial effect of higher training frequency on strength gains when volume was not matched. Hence, according to this meta-analysis, higher frequencies may PRIMARILY be permissive of more strength gains because they allow for higher volumes to be performed.
- The beneficial effects of increased training frequency seemed most prominent in multi-joint exercises rather than single-joint, upper body exercises rather than lower body, younger adults as opposed to middle-aged/older and women rather than men.
Right off the bat, it seems that frequency only potentiates strength gains when it allows for more volume to be performed. When only volume-equated studies were analysed, there was no significant effect of frequency on strength gains. This might lead you to believe that a higher frequency doesn’t directly improve gains in strength. It all comes down to the definition of volume.
In these studies, volume was defined as reps x load. This means the high frequency and the low frequency group had to do the same number of reps with a given load. In all likelihood, this meant that the low frequency group had to do more sets than the high frequency group in order to match their volume.
Think about it. If you do three sets of bench press to failure with 75% of your 1 Rep Max, you might be able to get 15 reps on the first set, 12 reps on the second set and 9 reps on the third. However, if you did 6 sets to failure, you might only get 7 reps on the fourth set, 6 reps on the fifth set and 5 on the last set.
So, if group A did three sets twice a week and got (15+12+9) x 2 = 72 reps, group B would also have to get 72 reps for the study to be volume matched. In practice, however, group B would have to do a TON more sets to match volume. If they got (15+12+9+7+6+5) = 54 reps, they would need 18 more reps to match Group A. This might mean an additional 3/4 sets JUST to be able to match group A. What does this mean?
Well, in most of these studies that equated volume, the lower frequency group had to do more sets, train for longer and accumulate more fatigue than the higher frequency group. In the real world, the higher frequency group just gets a better deal – less time spent training and less fatigue? Count me in!
If you think about it rationally, this also makes sense. Strength is specific – if you train yourself at doing something, you get better at doing that something in the way you trained it. You get better at shooting at basketball by shooting – if possible, with the same shoes, on the same field, with the same clothes as you would when it matters. That’s how you have the best practice. You don’t get better at playing football by shooting hoops.
At this point, you might be thinking to yourself: “Ok, what’s the dumb metaphor for?”. Bear with me for a minute. If you want to get stronger at lifting a weight for a 1 Rep Max when fully recovered, first thing in a session, what sort of training would be most specific to that goal? Well, lifting a 1 Rep Max, when fully recovered, first thing in a session. Which of the frequency groups best meets these criteria? The low or the high frequency group? The high frequency group does most of their sets while relatively fresh and recovered, while the low frequency group does a good chunk of their work while already fatigued. The high frequency group has a definite advantage in that regard! The training the high frequency group does is more specific to the 1RM test than the low frequency group.
Additionally, skill learning is facilitated when practice is distributed over time, not massed. This means that, volume being equal, you’ll probably learn to do a movement more easily when you do it more often rather than less often (when not taken to extremes).
With all that being said, that doesn’t mean you should NEVER train low frequency for strength. There are still situations that warrant lower frequency training, particularly when an athlete’s schedule is tightly constrained. Moreover, some athletes (perhaps due to level of advancement – though that remains to be proven) may simply not recover as well on a high frequency program as they do on a low frequency program – this is where individualisation comes into play. You might very well be an outlier, though you probably aren’t.
- When volume was matched, “[t]he average difference in weekly strength gains between groups was 0.41% , meaning the higher frequency groups gained strength about 21% faster than the lower frequency groups”
- Higher frequency was found to benefit virtually ALL strength measures.
- In direct comparisons, higher frequencies were associated with more strength gains, even when volume was matched, all the way up to 4-5+ times a week – though, at that high a frequency, the paucity of research precludes a firm conclusion being made.
- Again, effects were particularly meaningful for women and upper body pressing exercises.
This meta-analysis used volume-matched studies only. However, it found a positive impact of training frequency on virtually ALL measures of strength. The same tendency was found for women and upper body pressing exercises as in Grgic et al.’s meta-analysis. Few studies were found to actually show a benefit to lower frequencies.
As further reading, I highly recommend you go and have a read through Greg’s article. He takes apart the data in an understandable way, and I would only discredit myself trying to do likewise.
So, one older review found that when volume was equated, there were no differences between frequency groups. Another more recent review concluded that there was a dose-response relationship between training frequency and strength gains when volume was equated. The meta-analysis by Greg Nuckols had methodological differences with the one by Grgic et al. that might have resulted in the differences. My temporary and tentative conclusion on the topic of frequency and strength would be that increasing frequency probably has a positive effect of its own on strength gains. It has some evidence supporting it, and I can support it with a few mechanistic reasons as well. The effect of frequency on strength becomes particularly potent when it allows more volume to be performed.
Part 2, The effects of Training Frequency on Hypertrophy, coming soon!