Cluster Training: Heavier sets of 3 reps with 15 seconds rest in between
BTB Year 5 - Block 1 Clusters
In our last article about Cluster Training, we talked about how increasing ‘intra-set’ rest leads to increased tonnage Year 2 - Block 11. We’ll expand on that in this blog post.
For this block, our clusters are sets of 3 reps with 15 seconds of rest in between each rep. So in our main A series movements, we’ll go 1 rep, then rack it for 15 seconds. A 2nd rep, then rack it for 15 seconds. And then the 3rd rep, rack it, which completes the set.
But why would we do this from a program design standpoint? Read on.
“the nervous system takes upwards to six times the length of the muscular system to recover. ”
There is an inverse relationship between intensity and density in a training session. More volume means less intensity and more intensity means less volume.
Increased intensity requires more rest. There is no way around this simple fact because the nervous system takes upwards to six times the length of the muscular system to recover. So you may feel that fatigue at the muscular level but your nervous system is not ready to go again. This limits how much we can do in an hour-long training session. But there is a paradox to this because the higher intensity volumes we can hit in a training session, the better the end result.
With Clusters, we’re increasing the time between reps and increasing the amount of volume at a specific intensity. Without clusters, we can’t hit more than a certain amount of reps at a certain intensity. With Cluster Training, we can adjust rep max to hit higher volumes at certain intensities.
For example, normally we can hit 3 reps at 94%, now we could potentially hit 3 reps at 97% (because we have more rest in between each rep). This small % increase may not seem like much but if you start to calculate the numbers it becomes a big deal.
Suppose our 1RM is 100kg on back squat. Traditionally if we asked you to do a 3 rep max you would be able to hit 94kg - total tonnage being 282kg (94kg x 3 reps). With Cluster Training we may be able to hit 97kg for 3 reps - total tonnage being 291kg.
“As we start to expand that small increase over multiple sets and multiple weeks, it makes a huge difference.”
This may not seem like a whole lot now, but as we start to expand that out over multiple sets and multiple weeks it makes a huge difference. For three sets over four weeks equates a difference of 108kg (Cluster Training - 3492, Traditional 3384). That difference of 108kg over the course of four weeks has immense value in getting what we’re trying to accomplish.
Quality goes up with more intra-set rest
The other huge benefit of this training is that quality goes up with greater intra-set rest. Risk increases the closer we work at near maximal weight. If anyone has ever done a max set of three reps in a row, you know it’s scary going for the second or third rep when you are absolutely crushed from the previous rep. It is better (safer) to re-set and go again as opposed to ‘grinding’ through a set.
With intra-rest, we decrease the rate of fatigue that compromises technique by regrouping for 15 seconds between each rep.
we’re using training data from our members to influence program design
We get our data from KPIs. If you’re a member, you know about KPIs. If you’re not, KPI's are key performance indicators where we test members on bodyweight bench, pull up, hamstring strength, and jumps. The goal is to objectively measure how members are progressing from year to year after training with us.
When it came to jumps on the Forcedeck, we saw an inverted relationship between countermovement jump (CMJ) and squat jump (SJ). Normally we should see greater heights on CMJ compared to SJ, but we saw the opposite. Though we traditionally focus on concentric abilities, there still should be a greater ability eccentrically. SJ goes through a larger displacement and a pause at the bottom of the jump. The greater displacement depletes built up elastic energy and the pause takes away the amortization (the break between eccentric and concentric).
In fairness, we have been doing a couple of blocks with heavy concentric emphasis, so this is not that surprising. But what that means for training is we’ll use more plyometric and eccentric work within training. For that reason, we are going to incorporate depth drops, high eccentric loads and eccentrics with our primary exercises.