Earlier this year, a new research study was published that suggested that hopping could make you faster. As is usually the case, this led to headlines in running related media outlets suggesting that runners could follow the experiment protocol to get faster.
I first heard about the study because someone on Reddit shared it – literally asking if they should start doing this every day.
As far as research studies go, it’s not bad. They’ve got a clear research question, experimental protocol, and analysis. They come to a conclusion, and they’re able to articulate some rationale to support their findings.
My problem is not so much with the study itself – it’s with the idea that it’s immediately applicable and transferrable to training. I think this is a good example of a study that establishes a finding, and that the finding should be investigated further to determine how it best fits into a training regimen.
Instead, the media ran with it as solid training advice – and the researchers encourage this with their framing around marginal gains. That claim, to me, is the most questionable part of the whole study.
But first, let me briefly summarize the study and it’s findings.
What Did They Study?
The study investigates the role of simple, daily plyometrics – specifically, hopping on two legs.
Their sample included 34 amateur runners. The two criteria were that they were less than 40 years old and that they could complete a 10k in less than 55 minutes. More on the sample later.
The experimental group performed a set of hopping exercises once a day for six weeks. They hopped for ten seconds at a time, with rests in between sets, for a total of five minutes. Over the course of the six weeks, the rest decreased and the number of sets completed increased.
Other than that, everyone kept training as normal.
Before and after the experiment, they put the participants on a treadmill for an exercise test. They measured their oxygen usage and their respiratory exchange rate at different speeds (10, 12, and 14 km/h) before increasing the speed and incline to force them to exhaustion.
What Did They Find?
Based on earlier research into plyometrics, they expected to see an improvement in running economy, especially at faster speeds. And that, essentially, is what they found.
Running economy is defined here as the amount of oxygen used to run at a given speed. Using less oxygen implies that you’re using less energy – and thus being more efficient.
Their main take away was that running economy improved as 12 km/h and 14 km/h, but it did not improve at 10 km/h.
Although when you look at their graphs and the data, it appears that running economy increased at all three speeds – but at 10 km/h it was just below the level of significance. I could digress and go on for a while about the role of significance – but I’ll leave that for another day.
Why Does This Matter?
According to the researchers, most previous research into plyometrics involved some combination of a) lengthy exercise regimens and b) elite athletes.
These lengthier sessions could include 30 minutes of intense work per week, involving multiple jumps and exercises. They surmise that their simpler, shorter daily exercises may be easier for amateur runners to implement.
The use of amateur runners is also important, because it suggests that there’s greater applicability to regular runners – as opposed to highly trained individuals who compete at a scholastic or professional level.
So Why Shouldn’t We All Start Hopping?
The findings seem pretty simple and pretty clear. Shouldn’t we all just start hopping?
There’s probably little harm in doing so. The main downside is the opportunity cost of what else you could use those five minutes for.
But the real question is – will this be helpful for you?
In the introduction, the authors start off in the first paragraph by framing things with the concept of “marginal gains” – “combining multiple small performance improvements in different areas to create a significant advantage.” But the problem with this framing is two-fold.
What’s the Baseline for Comparison?
First, pursuing marginal gains implies that you’ve already done everything else in your power to improve – or at least that you’re training at a high level.
When Eliud Kipchoge attempted to run a marathon under two hours, they already knew that he had maxed out the normal avenues for improvement. So they went after the little things that could add slight improvements to his performance – like arranging pacers in a specific pattern around him. Given his speed and ability, this could help him improve marginally. But someone running a four (or five to six) hour marathon would likely perceive little to no benefit from this.
When you look at the sample, it’s clear that these runners are not pursuing other avenues of improvement. By definition, they’re amateur runners. They are faster than average, with an upper limit of a 55 minute 10 km. But they only run 2-3 times a week, and they’re putting in relatively little mileage. They are casual runners, and they don’t appear to train at anywhere near a serious level.
That’s not meant to be pejorative. But it’s meant to highlight that the study isn’t saying that anyone can add five minutes of hopping each day and see improvement. It’s really suggesting that if you aren’t already doing a lot of training, this could be a good first step.
If you’re already training for marathons at a moderately high level – for example, you follow a training plan like Pfitz 18/55 or 18/70 – we don’t necessarily know how helpful this would be.
Does This Add On to Existing Training?
The other piece that’s left unanswered – and is quite important to the idea of marginal gains – is whether this is additive.
This is a better alternative to doing nothing. But what if I’m already doing something?
For example, what if I’m already doing hill sprints? Or if I’m doing some kind of skipping drills during my warm up? Or even just doing strides up hill?
These are all common training techniques, and for a more serious recreational runner it would be common for them to do at least one of these things at some point throughout the year. The movements are not the same, but they’re similar enough in nature to hopping.
And that begs the question – if I’ve already done some hill sprints, will hopping still lead to improvement?
If this is really about marginal gains, then the answer would need to be yes. Marginal gains implies you can layer this on top of existing training and see an additive effect.
But it’s quite possible that this is, instead, an alternative. There are likely lots of different ways to elicit this kind of response from plyometric-like training. This is important to know if you’re trying to fit this into an existing training regimen.
What Follow Up Questions Does This Raise?
In my eyes, this is a useful research study insofar as it establishes a basic fact – that hopping induces improvements in running economy – but not insofar as it offers solid training advice.
Instead, this should be interpreted the way most research should be – as a piece of a larger puzzle.
The authors offered a few avenues for further research. Before I considered this as training advice, here are some research questions that I think are worth further consideration:
- How does this compare to other drills and supplemental training? Is the effect additive if you combine multiple interventions? Or is the effect negated if you’re already doing a similar movement?
- How long does this effect last? Does six weeks of hopping produce lasting effects – or do they start to fade when the exercise stops?
- How long will improvement continue? Is three weeks enough to elicit a response? Does twelve continuous weeks elicit greater improvement?
Reflecting on this study, though, I am reminded of some advice Pete Pfitzinger recently shared on the Strength Running podcast.
In response to a question about marathon runners doing drills, his advice was basically: do something. If you’re doing nothing, then incorporating some skipping or other drills is likely some low hanging fruit that could help you improve.
I think hopping – as described in this study – falls in the same bucket. If you’re not doing anything like this, then it’s better than nothing. There are probably better, more optimal ways to incorporate this into your training. But this is a start.