Will Hangboarding 2x/Day Improve Your Climbing? (ULTIMATE Revised Breakdown 2023)

Hooper’s Beta Ep. 129

INTRO

Oh, how things have changed! Two years ago this crazy new finger training method took the climbing community by storm, with Emil and Felix Abrahamsson reporting incredible improvements in finger strength by hangboarding two times per day for 30 days. It seemed like a revelation, especially considering there was even a research paper to help explain how it all worked!

But now, two years later, both the Abrahamsson brothers and we at Hooper’s Beta have learned a lot, and it’s safe to say: our opinions on this routine are not quite the same as they originally were. So in this video we’re going in-depth to explain what’s really going on here (and what’s probably not going on -- which I think is even more useful). Most importantly, we’ll cover what this means for you, with insight into whether or not you should be doing this routine and how it compares to “normal” high-intensity protocols. By the end, you’ll know more about how hangboarding works than… pretty much anyone who doesn’t watch this video! So let’s get into it.

HOW DID WE GET HERE?

First, a brief recap of what got us here in the first place.

A 2017 research paper titled “Minimizing Injury and Maximizing Return to Play: Lessons from Engineered Ligaments”  details the results of an experiment by Paxton and colleagues involving tendon-like tissue (“sinew”). Among other things, they find that even when low-level loads are applied, the sinew responds with increased tenocyte activity and ultimately increased collagen concentration. They also find that anything beyond 10 minutes of loading does not change the response and that the sinew becomes unresponsive to further loads for six hours. These results lead one of the researchers, Keith Baar, to suggest that humans may be able to “improve tendon physiology” with a similar protocol: up to 10 minutes of low intensity exercise with at least six hours in between. Hoping they can leverage this to benefit their climbing, Emil and Felix loosely follow these guidelines to create their fingerboard protocol.

And what do you know? After Emil’s original 30-day challenge, his results are astounding. He sees huge gains in how much weight he can hang on the Beastmaker crimps, plus increased hang duration on a 6mm, 8mm, and middle Beastmaker edge. The brothers both note how much healthier and “less tweaky” their fingers feel while climbing. Then, in the two-year follow up video, Emil notes he was able to achieve a series of new strength and climbing benchmarks -- most notably 1-5-9 on the campus board and sending his first V15. He also mentions that he feels the strongest he’s ever been and credits the hangboard routine as an important contributing factor.

Now, considering this hangboard routine seems to fly in the face of every high-intensity protocol out there, we’re left with a glaring question: how could lightweight hangs have such huge benefits? And before you say, “it's all explained by the research paper and collagen synthesis,” you might want to hold that thought.

DOESN’T THE STUDY EXPLAIN EVERYTHING?

It would be a mistake to assume that the sinew study fully explains Emil and Felix’s gains for a couple reasons.

First, Baar’s recommendations about tissue loading, which Emil's protocol is based on, stem from an in-vitro study. Despite the sinew being grown from human tissue, the similarity to humans doesn’t go much further. Young, lab-grown sinew in a nutrient gel attached to cement anchors is a far, far cry from something like a real tendon in an adult man’s hand hanging onto a board. Baar even mentions the sinew has a much higher rate of collagen synthesis than a normal tendon, among other key differences. Plus, as we’ll see later in the video, evidence about connective tissue growth in real-world scenarios doesn’t necessarily line up with these sinew study results. While we certainly shouldn’t discount in-vitro studies as useless, we should be aware that in-vitro results are frequently found incompatible with real-world findings. So, we shouldn’t assume the sinew study’s findings also happened to Emil.

Second, Baar’s recommendations are, understandably, quite open-ended. That leaves room for tons of other variables that could affect Emil’s results. The only specific part of the sinew study Emil could have followed was the time under load -- 10 minutes. But Emil actually chose a much shorter duration because he wisely wanted to play it conservative. So, when we look at how Emil’s protocol actually compares to sinew study, the two aren’t exactly equivalent, and Baar’s recommendations are too broad to control for most variables.

To me, and hopefully to you, this means we shouldn’t be so quick to use the sinew study to draw conclusions about Emil’s result. To truly explain that, we need to look at other possibilities, and this is where we learn a *lot* about how hangboarding works… and doesn’t work.

MECHANISMS

Let’s determine which mechanisms could be causing Emil’s gains, in order from least likely to most likely.

1. Muscular Hypertrophy

In simple terms, muscle hypertrophy is when a muscle increases in size. This is relevant for climbers because we rely on our muscles to get us up the wall, and the cross-sectional area of a muscle is the biggest determining factor of its strength. This is a huge, often overlooked aspect of how something like hangboarding can help climbers progress. Hangboarding involves an isometric contraction of all sorts of muscles, most notably the finger flexor muscles in our forearms. Under the right conditions, that isometric contraction can cause our muscles to adapt by increasing in size...aka, hypertrophy. Growing flexor muscles is one of the main ways hangboarding increases our finger strength. So that must explain Emil’s gains, right? Actually, for his specific protocol, probably not.

To be fair, the fact that Emil’s hangs were very low-intensity doesn’t necessarily mean they couldn’t have caused hypertrophy. Research shows loads as low as 30% 1RM can lead to muscle growth, but there’s one big caveat -- you need to achieve a threshold of total work done by the muscle. In other words, while the individual reps don’t *have* to be high-intensity, the muscle won’t grow if you don’t give it enough stimulus over the course of the workout. You don’t have to go all the way to failure, but you need to get in the vicinity if you’re doing low intensity reps, and most research indicates higher levels of fatigue are needed to maximize hypertrophy. Emil’s protocol is specifically designed to stay far away from fatigue, so it’s extremely unlikely even 2x per day was enough for his hangs to induce muscular hypertrophy -- especially considering Emil is not some random untrained research participant but a highly experienced athlete. That means we can confidently rule out increases in muscle size as a direct result of Emil’s protocol.

Sidenote: if you did want to try to force muscle hypertrophy with Emil’s protocol, you could do blood flow restriction, as that can drastically increase muscle fatigue even with low loads.

2. Connective Tissue Growth

What about the tendons and ligaments in our hands? Maybe the low-intensity hangs are enough to cause those to grow, strengthen, and ultimately increase our finger strength.

Unfortunately, relevant research on something like tendon growth protocols is hard to come by in general and non-existent for climbers specifically, plus hypertrophy studies are always focused on muscles. Of course, that’s not to say growth does not occur in connective tissue; on the contrary, we know it does. For example, we have empirical evidence showing climbers can have significantly thicker pulleys than non-climbers [13]. We also have evidence that Achilles tendons can increase in cross-sectional area when participants perform high intensity (90% volitional max) exercises. Notably, the Achilles tendons did not grow in people performing lower intensity exercises. So while we don’t have enough data to say exactly how Emil’s hangs affected his connective tissue, we can make some educated guesses.

Given the current evidence, it appears connective tissue grows under similar conditions as muscles, meaning relatively high fatigue or high load is required in trained individuals. This may not be the case with damaged tissue or in untrained individuals, but Emil is a presumably healthy, well-trained athlete. Therefore, the extremely low fatigue in Emil’s protocol makes it unlikely to have caused meaningful thickening of his tendons and ligaments.

3. Tendon Stiffening

Another factor to consider is the elasticity of our tendons, which has been shown to change under certain circumstances. This is important because tendon elasticity affects our strength as well as injury risk. This is one of the main factors we discussed in the first video we made in response to Emil’s original video. However, since then my opinion has changed.

Originally, we cited research showing that isometric exercises can increase tendon stiffness as a plausible explanation for why Emil’s hangboarding seemed to work, noting how stiffer flexor tendons could in theory lead to increased finger strength. Upon further inspection, though, I think a few key details somewhat undermine this argument.

Mainly, exercises performed in tendon elasticity studies are done at a much higher intensity than Emil’s protocol. One showed increases in stiffness with a 70% 1RM exercise [4]. Another study involved 25%, 50%, and 100% 1RM exercises, and showed no change in tendon stiffness in the 25% group, small change in the 50% group, and the most change in the 100% group. And a third study showed only 90% 1RM had significant effects on tendon stiffness compared to lower intensities. Overall, most of the research only shows moderate to high intensity exercises increasing tendon stiffness, around the 70-100% 1RM range, though smaller effects could still happen at milder intensities.

Now, this research is not perfect, nor is it perfectly applicable to us climbers. It was not performed on climbers, it was not performed on finger flexor tendons, and it was mostly performed on untrained or moderately trained individuals. Ultimately, though, I think the evidence suggests that Emil’s protocol was probably not high enough intensity to meaningfully increase flexor tendon stiffness. I’m definitely not convinced there was *zero* tendon stiffening, and perhaps even a small change could produce some interesting results, but I think it’s highly unlikely that tendon stiffening led to any large improvements or increased risk of injury.

But what about ligaments? Couldn’t those stiffen too? What if stiffer pulleys increased Emil’s crimp abilities? It’s certainly possible, but research on ligament stiffening suggests it happens as a byproduct of thickening, and as we learned in the previous section, notable connective tissue thickening seems to result more from high-intensity stimulus -- so, again, probably not applicable in Emil’s case.

4. Recruitment

One of the more interesting and commonly referenced explanations for why Emil’s routine worked is “recruitment.” Some argue that Emil’s hangs caused a neurological change that allowed him to access strength that he previously couldn’t. In other words, his muscles were strong, but something was limiting them -- and this protocol removed whatever that obstacle was. Could this be true?

Well, it’s definitely true that our muscular strength is not just limited by the muscle tissue itself. Our brains and central nervous systems often limit our peak force output to make sure we don’t go overboard and hurt ourselves. Also, sometimes our nervous system simply has not learned *how* to produce high forces efficiently -- there is “noise” in the signal that prevents optimal output. Luckily for us, to some extent those barriers can be removed with training. By teaching our nervous system that we can handle higher forces without injury, and by training ourselves to produce those forces on command, we essentially “recruit” more strength. We can increase the total force output of a muscle, increase how quickly it produces that force, and decrease the stimulus required to do so without changing the muscle tissue itself.

Since the benefits of recruitment training tend to revolve around high force and/or high speed output, recruitment protocols tend to be similarly high-intensity. Low-intensity exercises will not automatically improve high-threshold recruitment because you’re simply not activating the right motor units. You may increase the ease and speed at which the *low-threshold* motor units fire, but that’s about it.

So, what does all that mean? Low-intensity recruitment training could improve your low-intensity performance, but almost certainly not your high intensity performance in a meaningful way. And unfortunately, very low-intensity finger strength recruitment just doesn't seem relevant to climbers, especially trained boulderers whose performance is centered around short bursts of high- to maximal-strength output.

In summary, while this idea is intriguing, Emil’s protocol appears too low-intensity to cause useful strength recruitment.

5. Connective Tissue Remodeling

Not to be confused with thickening or stiffening, connective tissue remodeling is when the collagen fibers essentially change their alignment or orientation. The fibers that make up our tendons and ligaments are not always perfectly aligned, especially where injuries have occurred. If the fibers are haphazard, the tissue is not as strong. Applying force or stretch to the tissue causes increased activity from little cells called tenocytes, while also “uncrimping” the collagen fibers, both of which can improve the orientation and the strength of the tissue. Research shows tissue remodeling can occur in damaged Achilles tendons even with something as simple as massage [17], so it’s reasonable to think Emil’s protocol could have caused *some* remodeling in his fingers.

On the other hand, numerous animal studies indicate that high volume or hypertrophy-like training has a much higher impact on remodeling than low-fatigue training. And, remodeling in untrained and/or injured tissue is much more pronounced than in trained and/or healthy tissue. Since Emil’s protocol is low-intensity, low-fatigue and he is a highly trained individual, any remodeling that did occur wouldn’t be hugely significant -- probably enough to contribute to his results, but certainly not enough to fully explain them. That is, unless Emil and Felix’s connective tissue was significantly damaged, in which case the remodeling effects would probably be greater.

In general, gentle tissue loading is seen to have numerous benefits for rehabbing injuries and is something I prescribe in my practice all the time. The reason I’m not fully convinced tissue remodeling is the *main* mechanism of Emil’s protocol is because neither of the brothers reported having serious finger injuries, only a sort of generic “tweakyness.” And that’s where this final mechanism takes the cake.

6. Pain Science

One of the most notable changes Emil and Felix expressed after performing these low intensity hangs was that their fingers felt healthier, less “tweaky,” and just more “solid” overall. This opens up a huge can of worms as pain science is a complicated field and I’m certainly not an expert in that regard. But, it’s still worth discussing the basics, because I believe this may have indirectly been the biggest contributor to the brothers’ gains.

There is a psychological aspect to pain science and a more physiological one, but the two are hard to separate so we’ll discuss them together. Similar to what we learned in the recruitment section, when we have pain, our bodies will naturally want to decrease force production in that area. So, no surprise, our fingers can literally be weaker if they feel painful -- regardless of the tissue’s actual strength. This can also create a bit of a feedback loop where we become conditioned to expect pain in certain situations, which can cause even more strength attenuation, fear responses, and even exaggerated feelings of pain. This then creates a set of rules in our brain, particularly in the prefrontal cortex, that help determine what we will and will not allow ourselves to do, both consciously and subconsciously. So, of course, if Emil’s routine somehow eliminated pain or discomfort in his fingers, it would make a lot of sense that they would feel -- and literally be -- stronger. But why would low-intensity hangs accomplish this specifically?

Studies have shown that some isometric exercises can alter our acute pain response through a complex mechanism. This includes decreased excitability in our nociceptors (pain receptors), attenuated pain response in the central nervous system, as well as a psychological change in response to the painful stimulus. Essentially, your pain receptors are less active or excitable, your CNS is better able to dampen the pain response and the inhibitory interneurons, and you can change your perspective of that stimulus. It would be fair to argue that this is a form of recruitment, but it’s not exactly strength recruitment in the traditional sense, so I’m considering it a separate mechanism.

Regardless, as a result, your body’s “rules” have been re-written. Instead of feeling tweaky, you feel healthy. Instead of worrying about an injury, you focus on trying hard. Instead of feeling average, you feel psyched. Instead of trying to avoid an injury, you try to finish your project. Instead of performing the way you always do, you perform better. And wallah, in a relatively short amount of time you’ve made significant gains in your climbing and training metrics. In fact, that’s exactly what Emil and Felix did.

7. Other Plausible Mechanisms

Finally, there are of course several other, far more vague, less interesting explanations for all of this that could still absolutely have caused some or all of Emil’s results. They’re quite speculative, but shouldn't be ignored. These include the possibility that simply increasing the amount and frequency of low-load activity had some unknown physiological effect on Emil, kind of like how people that get 10,000 steps every day tend to be healthier than people that are totally sedentary. More activity tends to be healthier than less provided we can appropriately recover from it.

Another, bigger factor is that there are a million other variables we can’t account for in Emil’s situation, like his diet, sleep, personal life, mindset, etc. Often these “boring” variables have much larger effects than we like to admit. And speaking of boring variables, we’d be remiss if we didn’t mention the placebo effect. Yes, I know, no one wants to admit that their brain made some things up that consequently became their reality, but it can, does, and will continue to happen. With that out of the way, it’s time for some conclusions.

WHAT HAVE WE LEARNED?

So, what have we learned?

Upon analysis, I do not believe the effects observed in the engineered sinew study, like increased collagen concentration from light loading of the sinew, were replicated by Emil or Felix to an extent that would account for all of their results.

 When we look for other more concrete mechanisms, we find the following:

1. Muscle hypertrophy appears unlikely -- the hangs are too low-intensity.

2. Connective tissue thickening in significant amounts appears unlikely for the same reason.

3. Stiffening of the tendons may have occurred in small amounts, but generally seems to require higher intensity.

4. Strength recruitment might have happened at some level, but probably not a significant or useful amount as the intensity was so low.

5. Connective tissue remodeling probably contributed to Emil and Felix’s results, though the amount is quite dependent on how unhealthy their tissue actually was.

6. Pain science is almost certainly at play, with diminished discomfort leading to psychological and physiological improvements, more and better training, and ultimately improved performance.

7. “Boring and unsatisfying but equally important other mechanisms” almost certainly had a large effect, though it’s impossible to prove how much. Increased activity, increased blood flow, increased awareness, unaccounted-for variables, and the placebo effect probably accounted for some or all of Emil and Felix’s gains.

So what does it all mean? To be honest, I think there are many factors beside this fingerboard protocol that contributed to Emil’s success. It would be foolish to ignore years of training and give all the credit to lightweight hangs. Smart training, hard work, and a healthy mindset is where gains come from in the long-term, and there's simply no getting around that. I believe it’s possible the fingerboard protocol had some positive effects, though I think its significance has been over-hyped in the climbing community. The evidence suggests Emil’s protocol caused some remodeling of his connective tissue, but also neurological and psychological changes to pain-related stimuli. This all probably caused some direct strength improvements, but more importantly allowed both brothers to climb and train harder. By pushing their limits with newfound confidence, they got stronger. So the fingerboarding helped open the door and the subsequent climbing and training pushed them through it, but they wouldn’t have found the door in the first place without their prior experience and fitness base.

With all that said, just because it worked for the Abrahamssons doesn't mean you should do it too, so let’s wrap things up with some recommendations.

WHAT IT MEANS FOR YOU

So, should you be doing this routine?

If you’re hoping to replace high-intensity hangboarding with Emil’s routine, you should think twice. The mechanisms that make high-intensity finger training effective are not at play in these low-intensity hangs. If you’re hoping to accomplish certain feats of strength like 1-5-9 on the campus board or hanging on 6mm edges, Emil’s protocol is not the way as those require specific strength training that low-intensity hangs don’t provide. When it comes to building strength long-term, high- and low-intensity exercises are not interchangeable. 

If you’re totally new to climbing or feel intimidated by high-intensity hangboard protocols, Emil’s protocol is a virtually risk-free way to build confidence with fingerboarding positions, allowing you to start with as low of an intensity as you want with no extra gear required. Even more experienced climbers can use this method to experiment with grip positions and uncover useful insight about grip preferences, finger morphology, specific weaknesses, etc.

If your fingers feel healthy and you’re currently seeing good progress with your high-intensity finger training, I see no strong need to add this low-intensity protocol into the mix. You certainly can if you want, but your time could be spent on more productive things such as improving mobility, addressing that nagging shoulder issue, etc.

If you’re looking for a nice, gentle warm-up, I think Emil’s protocol can be useful. It’s definitely not a complete finger warm-up, but especially for people who always tend to feel tweaky in the beginning of sessions, spending more time specifically loading your fingers safely is worthwhile. Don’t get too caught up on the “six hours in between session” aspect. If you’re using this as a warm up, you can proceed to climbing immediately afterward.

Lastly, if your fingers feel “tweaky” and not so great like Emil and Felix’s did, I think this protocol is worth considering. The only reason I’m not 100% behind it is because there are other methods that can help with these issues that I often prefer as a PT. For example, farmer crimps or “no hangs” provide a much more consistent, trackable load. Also, if you're in any kind of pain, I generally recommend figuring out what the actual cause is if possible. Are you ignoring an injury that needs rest and rehab? How’s your sleep? Diet? Are you managing your training load well? Are you going to exhaustion every session? Proper diagnosis is invaluable, though not always possible. Overall, I do think increasing the frequency of light loads to our fingers can be quite useful, and it is something I prescribe to some patients as a way to promote healing.

CONCLUSION

If you enjoy ultra-thorough breakdowns like this please support the channel by subscribing, buying a t-shirt, telling your friends, or whatever you want! And if there’s something you’d like to add to the conversation, please share in the comments below so we can all continue to learn together. Until next time: train, climb, send, repeat!

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DISCLAIMER

As always, exercises are to be performed assuming your own risk and should not be done if you feel you are at risk for injury. See a medical professional if you have concerns before starting new exercises.

Written and Presented by Jason Hooper, PT, DPT, OCS, SCS, CAFS

IG: @hoopersbetaofficial

Filming and Editing by Emile Modesitt

www.emilemodesitt.com

IG: @emile166

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