May
11

The Science of Going Downhill Faster

While it doesn’t happen very often, sometimes the sports science world turns its eye on real mountain biking. Most studies for “cyclists” – which is really just a code word for road riding –are conducted in labs and on the road. This makes their application to the realities of trail riding somewhat limited, which is why it is always good to see someone use science to look at what is actually happening when we ride our bikes on dirt.

Earlier this year a study was published that looked at what it takes to be successful at Downhill Racing. This study was conducted by a team of researchers in the UK and it was unique in that it looked at more than just the usual cardio factors like VO2Max and Anaerobic Power. They realized that things like skill levels, self confidence and hand-grip endurance also played a role, so they set out to see what exactly contributed the most to DH racing performance.

What they found was pretty interesting and worth checking out for anyone who races downhill. It really calls into question the usual approach to training for this unique sport and seems to support some of my “radical” notions about the best ways to approach improving your DH race times.

And while the study was looking specifically at going downhill really fast, there are a lot of of applications no matter what type of riding you do. Getting better at descending with more speed and confidence is pretty high on most rider’s wish list and knowing what it really takes to do that can help you make smarter training decisions.

In this article I want to go over this study, explaining what they found and what their conclusions were from it. I also want tell you what it all means for you…at least from my point of view. Hopefully you find something from it all that can help you ride faster and with more confidence on the trail.

88003d96ebff76b91ac4c860c940417d

Image by “Cycling” on Pinterest

The Study

The overall study looked to identify “physiological, psychological and skill characteristics that explain performance in DH racing”. It comprised 4 mini-studies, with each one looking at different aspects that could contribute to performance. While I’ll give you an overview of the study, you can read the official summary and access the full published study by clicking here.

The first study looked to “identify factors potentially contributing to DH performance”. They surveyed an expert panel to establish what factors they thought were most important in the success of a DH racer. The panel comprised a group of 1 team manager, 1 team mechanic and 4 Elite riders and 1 sports scientist. After their results were gathered they sent those results in the form of a survey to 50 DH riders, asking them to rank the importance of those factors on a 6 point scale. 35 of them responded and their results were combined with the panels for the final rankings.

The second study looked to “develop and validate a measure of rider skill”. They asked an expert panel to create a list of important skills and then use it to grade riders on a 10 point scale in those skills. They were then shown 50 second video clips of riders in a recent DH race and asked to grade their skills, which also gave them an average score for each rider. They weren’t told anything about the riders and did not know how they placed when grading them.

The third study looked to “evaluate whether physiological, psychological and skill variables contribute to performance at a DH competition”. They went to a UK regional downhill championship event and tested 43 riders there of various ages and abilities. They were tested in aerobic capacity via a step test, lower body anaerobic capacity via 30 second Wingate test, hand grip endurance via squeezing on an dynamometer at 5 second intervals for 5 minutes, self-confidence via a survey before the race and skill level via video analysis as discussed in the second test.

The fourth study looked to “test the specific contribution of aerobic capacity to DH performance”. They had 10 riders and was comprised of two tests itself. The first had riders come into the lab to test VO2Max and Ventilitory thresholds. The second test had those same riders simulate a DH race run while having their heart rate and exhaled gases monitored. They were also tested for hand-grip endurance by testing their grip at the beginning and the end of the run.

The Results

CA-Prison-case-study

The first study ranked Technical Skill as the most important factor with Self Confidence coming in second. Aerobic Capacity and Lower Body Anaerobic Capacity came in after that with Bike Set Up and Past Experience rounding out the list.

The second study resulted in a list of skills and a 10 point grading system that showed a high level of agreement among the coaches with how they were scoring riders. This scoring system was then used to grade the rider Skill Levels in the third study.

The third study found that Skill Level (as scored from 50 second video clips shown to coaches in the second study) and Hand Grip Endurance were significantly related to performance. They found no correlation between Aerobic Capacity, Lower Body Anaerobic Capacity or Self-Confidence and performance.

The fourth study found no correlation between aerobic capacity and performance. Peak values obtained during the simulated race run were less than what was obtained in the lab for VO2Max, minute ventilation and heart rate. However, breathing rate was actually increased compared to what was observed in the lab. They also found that Hand-grip Fatigue had a modest but significant correlation with performance.

Their Conclusions

At the end of the study they concluded that Skill Level and Hand-grip Endurance explained 73% of variance in ride times. They were the only factors that showed a significant correlation with performance and both of them came up twice in the study as being important.

The role for aerobic capacity was only partially supported by the data and there was no direct correlation between it and performance. It was obvious that there was a large aerobic demand but they couldn’t establish a link between VO2Max and how a rider actually performed.

Self Confidence didn’t do well in analysis of the third study but it was ranked as the second most important factor by the riders surveyed in the first study. After looking at the numbers they concluded that Skill Level feeds into Self Confidence and that feeds into performance.

Maximal anaerobic power was also unrelated to performance but they thought they might find a better correlation to the ability to repeat those anaerobic efforts “as previously shown in cross country mountain biking.”

Their conclusion was that the most important factors were 1) Rider Skill, 2) Hand-grip Endurance, 3) Self Confidence and 4) Aerobic Capacity “tentatively presented in order of importance”.

What it all means…at least to me.

At the end of the day Rider Skill was the most important factor, which means that developing your skills is the best thing you can do to get better at going downhill. And one of the best ways to do this is to focus on mobility training so you can efficiently get into the right positions on your bike. I can show and tell you all day long how to execute a skill but if you lack the mobility and/ or body awareness to get into the most efficient positions then it doesn’t matter. Knowing what to do only helps if you can actually do it.

It also means that you need to spend time working on your skills. Whether it is doing drills in a parking lot or spending dedicated time during rides focusing on specific skills – or preferably both – you have to use focused practice as a big part of your training program. Just riding your bike will only get you so far and making sure you can move efficiently and then can apply that movement properly to the bike is the fastest way to getting better at descending.

Hand-grip Endurance was the second most important factor but remember that, as Gray Cook puts it, your grip is a window to your core. This means that true grip strength and grip strength endurance come not directly from the hand but in creating a strong, functional core that syncs up efficiently with your hand/ grip. This is why things like deadlifts and swings create the type of synergistic core and grip strength endurance you need to improve your Hand-grip Endurance on the bike.

These were the only two factors in the study that showed a strong correlation to performance. So far the science tells us the best way to get faster at going downhill is to focus on Skills (which includes mobility training) and Hand-grip Endurance (which includes overall functional body strength). Both of these factors can be significantly improved with a good training program that focuses on improving your mobility and strength while spending time on the bike focusing on skill development.

Self Confidence was also found to be important by the riders surveyed and once you see how Skill Level improves Self Confidence you can see how they are related. Besides the connection between moving better on the bike and feeling more self confident you can also use proven methods to improve your mental focus both before and during a ride. This means that Mental Training can help improve your performance as well.

Despite setting out to show that it played an important role in performance and setting up a test to look specifically at it, Aerobic Capacity didn’t turn out to be as important as they had thought. While it obviously plays a role in DH performance, it isn’t more important than several other factors. This makes sense when you realize that after a few years of riding your Aerobic Capacity levels off – no ones VO2Max improves forever – and then improvements usually come from other factors like improved movement efficiency (a.k.a. skills), sport specific strength and self confidence/ mental focus.

Focusing on leg power may be less important than the ability to sustain and repeat your efforts. On the race runs riders only achieved 9% of the peak power observed in the lab and only spent 55% of their time pedaling, with that broken up into multiple shorter efforts. It seems that being able to lay down power quickly is more important than what you can peak out at and being able to repeat those efforts over the course of a run is the ultimate goal.

The increased breathing rates observed on the trail were very interesting when viewed in light of the decreased cardio demands compared to what was measured in the lab. Peak cardio levels were lower during the DH race run, which means that riding on the trail was “easier” on the cardio system than how hard you can push during a lab test. The authors suggested that the increased breathing rate was because you had to hold your breath and use the Valsalva Maneuver to stabilize the spine during impacts. I think anyone who has ridden a bike downhill would suggest that they were right.

This tells me that the ability to use the breath to absorb impacts is an important skill we need to develop, which is something that kettlebell swings do a wonderful job of. It also speaks to the unique cardio demands of the trail and how you can’t simulate them in the lab or on the road. In other words, trail riding is the most important and specific cardio training you can do.

Now lets compare what this study found to the usual approach a rider takes to improving their downhill riding performance. When you do this you see that things are usually flipped. Aerobic Capacity and Anaerobic Power are emphasized while Mobility, Skills and Mental Training are are marginalized. Strength Training is also important (it will improve Hand-grip Endurance among other things) and while it is used more often than in the past, it is still often left out or used as another form of Anaerobic Capacity training i.e. bootcamp type workouts.

This means that most riders spend too much time focused on the wrong factors. While Aerobic and Anaerobic Capacity are important, they aren’t more important than other factors that often get marginalized or neglected. Skipping or minimizing Strength, Mobility, Skills and Mental Training in order to spend more time on a trainer or road bike working on your cardio isn’t the best way…or at least that is what this study suggests and my experience confirms.

You have to spend time working on your mountain bike specific mobility, strength and skills if you want to ride with more speed and confidence when the trail starts to point down. Until something points me in another direction I’ll keep advocating a balanced approach that recognizes the crucial role improving your mobility and strength play in how well you can ride a bike downhill.

And now for the “that’s not what I said” portion of the article…

bff3079e85f5597f17a28853b46967a6

I am not saying that cardio isn’t important or that you don’t need to work on it. Anyone who has done one of my programs can tell you that you spend a good amount of time working on your cardio. I’m just saying that making it the focal point of the program and minimizing these other factors isn’t the best way.

I also know that there were limitations to the study and that you can poke all sorts of holes in it if you really wanted to. Some riders are sold on the need to focus their training time on cardio over everything else and if you’ve had success with that approach then I can’t argue with you about that. The point isn’t that this study is definitive, simply that it is a unique look at the demands of DH racing and it is interesting to see what it tells us and how those things correspond with what I’ve observed working with riders at every level for over 10 years now.

Hopefully this study and what it tells us can help you make more informed decisions about the best ways to train for DH racing or just getting better at riding the descents you have to face on your local trails. Mountain biking – in all its forms – is a unique sport that requires a smart, balanced approach to improvement. Making smart use of mobility and strength training can help you in a lot of ways and now we have some science that seems to confirm that.

Until next time…

Ride Strong,

James Wilson

MTB Strength Training Systems

The Ultimate MTB Workout Program

The Ultimate MTB Workout ProgramThis workout program is designed with one simple purpose – to be the best mountain bike training program on the planet. When you are ready to take your training program to the highest level possible then you can’t do better than this workout program. Based on my years of working with some of the best riders on the planet, this truly is the Ultimate MTB Workout Program.
Learn More

Social Comments:

WordPress Comments:

  1. Greg Hart says:

    Hi Guys,
    Great debrief on study James. I was particularly interested in the breathing rate and the use of the ‘Valsalva Maneuve’ is stabilise the spine from the impacts experienced while defending. This reminded me of a martial art move I was taught a while ago by a Grand Master however the stability was generated by increasing static muscular tension the lower abdominals and obliques to coincide with impacts and was also regulated and timed with exhalation patterns. The reason that this technique may be an improvement over generating pressure in the upper torso is that when the ‘Valsalva Maneuver’ is performed in this way it decrease what they medically call ‘preload’ to the heart, which is essentially the autonomic system reducing blood flow volumes as a reaction to the increased internal pressure in the chest area generated by the maneuver. (see here for medical clarification of this process https://www.youtube.com/watch?v=rtGg9j8yJTc . The point being that if this manever is engaged enough during a DH race it will decrease blood flow to the heart which may translate to a reduction of oxygenated blood to the brain required for high level cognitive processing critical to making instantaneous decisions on the decent. I think this could defiantly, from a physiological point of view, impair performance. What are your thoughts of this perspective?

    Reply • May 11 at 8:18 am
    • bikejames bikejames says:

      I know what you mean in that a true Valsalva Maneuver isn’t what you want on the trail. You aren’t trying to poop (which is the most common use of the Valsalva Maneuver) and you need a more subtle approach to stabilizing your spine than that. The ability to “ground” yourself to absorb an impact without getting stiff and placing an undue stress on the cardio system is a skill that has to be trained. I like swings because you can’t stay stiff and do 20+ swings with a decent weight – you have to learn how to time your tension and use your breath to help you or else you will gas out quickly. Good catch on the difference between a true Valsalva Maneuver and what we are really looking for on the trail. While they are related they certainly are not the same thing.

      Reply • May 11 at 9:32 am
  2. Greg Hart says:

    Just a quick follow up on my previous comment. James’ kettlebell swing movement encourages the stabilising tension of the Valsalva Maneuve to the lower region (similar to the martial art technique) of the body potential reducing the ‘preload’ effect in the upper chest cavity. And there may be medical support for it to improve performance.

    Reply • May 11 at 8:27 am
  3. Mark Buckley says:

    Hi James that’s for highlighting this article. I also found it a while ago and found it very interesting. I think however you have misrepresented the aerobic capacity data. The conclusion to the fourth study was that the v02 data showed downhill riders have a reasonable large aerobic capacity, admittedly from the studies data not as large as pro road racers , cross country skiers etc. I think an over emphasis on strength, mobility etc at the detriment of developing aerobic power will result in sub optimal performance. A balanced approach to development that emphasises all the desired elements would be better, after all mountain biking is predominately an endurance sport, very different to road riding/racing but still endurance s base. I am a fan off your work have bought a couple o f your programmes but sometimes I think you sell the message of strength maybe a little to hard! To support your stance with a little more science have you seen Ronnesstad et al Strength training improves performance and pedalling characteristics in elite cyclists Scandinavian journal of medicine and science in sports 2015 : 25 e89 – e98? Interesting read done on road cyclists, but I’m sure you can extrapolate something useful from their findings!

    Reply • May 22 at 2:27 am
    • bikejames bikejames says:

      Thanks for the feedback. Sorry if there was some confusion about my conclusions, in the “That’s not what I’m saying…” portion of the article I pointed out that I am not saying that you don’t need to train your cardio or that it isn’t very important. I’m pretty sure I also used the term “balanced approach” as well in my conclusions. Can you point out where I gave the impression that focusing on strength and mobility to the detriment of aerobic power is the best way to go? I need to fix it if I did say that because that is certainly not what I think or what I had intended to say.

      If not then all I said was that while cardio is important, it isn’t more important than these other factors. By focusing on cardio to the detriment of strength and mobility you will also hinder performance. In a sport that is obsessed with cardio training I have to speak up loudly about the benefits of strength and mobility training but in no way am I saying that cardio is not important.

      I also pointed out that the best cardio training you can do is on the trail and that other forms of cardio training aren’t able to challenge the system in the same way a trail ride can. You do need to do a lot of cardio training, I just consider trail riding to also be cardio training along with what you do on the road or a trainer. Too many riders don’t look at trail riding as cardio training and then spend too much of their other training time doing extra cardio when some of that time would be better spent getting stronger and more mobile.

      Mountain biking is an endurance sport but your cardio system is only one factor and over-emphasizing it isn’t the best way. I’m sure we agree on this approach and I’m sure if you re-read the article you will see you might have missed a few things I said to that effect.

      Reply • May 22 at 11:39 am
  4. David says:

    Hey James, do you know what your avg heart rate and peak heart rate is, on a typical extreme downhill descent? I would guess it would still be in the arena of 160bpm+ due to the adrenaline, and muscle exhaustion, from the full body stabilizing over the rough terrain, and periodic intervals of high cadence pedaling for position or time advantage.

    Reply • September 10 at 2:14 am
    • bikejames bikejames says:

      No, I don’t know because I’ve never worn a HR monitor on a DH run. I’d guess it is higher than people would guess as well. It is always funny when people say that riding downhill is the easy part!

      Reply • September 10 at 7:55 am
    • Jimmy says:

      I’ve worn a heart rate monitor on DH runs lots of times. If it’s a track where there’s a fair bit of pedalling at the start it’s easy to max out your heart rate if you go 100% out of the gate – the highest I’ve recorded is 196 bpm. I found over time though that for me personally, if my heart rate climbs above around 180 bpm then I actually start to perform worse and make mistakes. I’ve got to the point now where I can pace myself and keep my heart rate pretty constant at around 170 – 175 which seems optimal for me on a typical UK downhill track i.e typically between 2.5 and 4 minutes top to bottom.

      Reply • October 7 at 3:40 am
    • MattyBoy says:

      I’m pasting part of an abstract from a study on heart rates while DH mountain biking from 2012. The article also mentions a reduction in grip strength. http://www.ncbi.nlm.nih.gov/pubmed/23025296
      We characterised the physiological demands of downhill mountain biking under typical riding conditions. Riding oxygen consumption (VO(2)) and heart rate (HR) were measured on 11 male and eight female experienced downhill cyclists and compared with data during a standardised incremental to maximum (VO(2max)) exercise test. The mean VO(2) while riding was 23.1 ± 6.9 ml · kg(-1) · min(-1) or 52 ± 14% of VO(2max) with corresponding heart rates of 146 ± 11 bpm (80 ± 6% HRmax). Over 65% of the ride was in a zone at or above an intensity level associated with improvements in health-related fitness. However, the participants’ heart rates and ratings of perceived exertion were artificially inflated in comparison with the actual metabolic demands of the downhill ride. Substantial muscular fatigue was evident in grip strength, which decreased 5.4 ± 9.4 kg (5.5 ± 11.2%, P = 0.03) post-ride.

      Reply • August 16 at 9:43 am
      • bikejames bikejames says:

        Thanks for posting, there definitely seems to be a trend towards grip strength endurance playing a direct role in how well you can descend.

        Reply • August 16 at 11:33 am
  5. David says:

    Agreed. I would say at 20-30+ on avg. in extreme downhill sections, the adrenaline, plus the braking, all the obstacles, jumps, landing recovery, and stability control on top of the pressure to win the race, my best guess is an anaerobic zone of 140-160BPM avg. Extreme MTB racers must have solid cores!

    Reply • September 10 at 4:35 pm
  6. David says:

    *20-30+MPH

    Reply • September 10 at 4:36 pm
  7. Jimmy says:

    Hi James, what was the list of skills the panel came up with in the second study?

    Reply • October 7 at 3:28 am
    • bikejames bikejames says:

      I don’t recall exactly, sorry.

      Reply • October 7 at 2:19 pm

Add a Comment

Your email is never shared. Required fields are marked *

*
*

Follow MTB Strength Training Systems:
James Wilson
Author and Professional
Mountain Bike Coach
James Wilson