Cycling Science and Myth Busting Part 2 with Stephen Cheung | EP#75
Part two of the interview with Stephen Cheung, PhD, co-editor of "Cycling Science". Stephen discusses key cycling questions and what we know and don't know about them from an evidence-based standpoint, while still making it understandable and actionable. He might even bust some myths.
In this Episode you'll learn about:
- (The science of) Pedaling technique
- (The science of) Cadence
- (The science of) Pacing
- (The science of) Strength training and cycling
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- There hasn’t been any good scientific evidence showing that consciously training yourself to pedal differently will have any benefits.
- These are things like pedaling at a different cadence, or "pulling back" or "throwing your foot forward at the top stroke".
- There are only very few papers comparing the pedaling mechanics of fitter individuals compared to less fit individuals.
- In one study, they had relatively non-fit, non-trained cyclists and cyclists who are fit and trained. They found a difference in their pedaling mechanics.
- They measured the EMG, the muscle activity across the legs, and they found some systematic differences on when particular muscles started and stopped firing.
- There’s a knowledge gap in this area. However, this presents a good opportunity now that there are so many power meter companies that track the right and left pedals separately.
Do we know something about bilateral asymmetry?
- Intuitively, we would think that pedal asymmetry is not a good thing because at any time you’re putting more force on one side of your body than the other, it may increase the long-term risk of injuries.
- I would love to see the data from using dual-sided power meters in real life situations, to see if there are differences in bilateral asymmetry or not. At the moment, we have no data to back up the intuition.
- To determine if you really need to get a dual-sided power meter like a Garmin, you have to weigh the cost-benefit of it.
- The two biggest uses for independent dual-sided power meters are if you think you have an imbalance in your body, and for bike fitters to really optimize a bike fit.
- There's no evidence that you can become more efficient at cycling by changing your pedaling style or technique.
- We don't yet know conclusively whether pedaling asymmetry has a role in e.g. injuries.
- There is a trend of riding at a higher cadence. The whole idea is that there’s less stress on the legs with each pedal stroke. This sounds great intuitively.
- But it really isn't that simple. Some people for better or worse are just big gear grinders with relatively low cadence. This is where they are most efficient and comfortable.
- Whereas some people tend to have really high cadence because this is what they are most comfortable with.
- In terms of pure absolute efficiency, the highest efficiency values are actually at about 50-60 rpm in tests done in the lab.
- Anything higher like 70-100 rpm, will be less metabolically efficient. However, this is lab based. This is not how we ride in the real world.
- It comes down to your own experimentation and what you feel is most comfortable.
- It’s certainly valuable to train your body to do something different and add that variety, where you are recruiting different muscles. You are having different neural activations.
- However, I don’t think it’s necessary to make it a goal to ride at a specific cadence. You have to stick with what your body is naturally most comfortable with.
- A bike fit plays a huge role in cadence. For example, if you’re a triathlete and you’re in a very tucked position and you’re riding big cranks, it’s impossible for you to comfortably spin at a high cadence because you are in this extreme position.
- In this case, a shorter crank can be a huge benefit because it puts your lower body into a more moderate range of position. You can generate more power comfortably this way.
- There's no evidence to suggest that there's an optimal cadence
- The optimal cadence for you is where you feel most comfortable and efficient.
- For triathletes in a tucked, aerodynamic TT-setup, shorter crank lengths may be beneficial to make it a bit easier to naturally increase cadence.
- The main difference between a triathlon bike leg and a time trial on the road is that you still have a run coming up after the bike leg in a triathlon.
- It’s about covering the triathlon bike leg distance as fast as you comfortably can without tiring yourself too much so that you will remain in good shape during the run.
- With that in mind, you don’t want to be going out hard at the start of a bike leg of a triathlon. Unless it’s a draft legal one where it’s worth it to spend that energy to make sure you’re in that front pack, because you’ll be saving so much more energy.
- In a non-drafting one, for example, if it’s a 40k Olympic distance triathlon, I would spend that first 5-10k getting comfortable on the bike, settling into a good groove, and not worrying about the power output. I would build into that effort.
- Then, during the 10-30k part of the triathlon, I would be settling to as fast as I comfortably can.
- Then in the last 10k, this is where you need to know yourself very well so you can decide whether you would go hard or take it easy and conserve your energy for the run knowing that you’re a better runner.
- The biggest emphasis on this is, don’t start too hard in a non-drafting triathlon.
What do you do you come to a hill or encounter headwinds?
- If I encounter hills or headwinds where I would be going slower, I would go harder.
- Let’s say the average power that you can sustain is 250 watts. If it’s a short hill, I’m going to be standing up and really trying to hammer up that hill where I might be going at 350 watts for 30 seconds to a minute.
- If it’s a long hill, I’m not going to be riding at 350 watts but around 270-280 watts for approximately 5 minutes.
- You have to remember that in these cases, your speed is going to be much slower.
- The slower you go, the more time of your overall bike split you’re going to spending on that hill. You want to minimize that time.
- Then when you are coming down that hill, this is where you recover. You’re not spending 250 watts because you’re descending very fast anyway.
How do you know when to stand up or when to remain seated on the bike?
- I stand up for a break from the regular position to give myself a little stretch.
- I stand up if I know it’s a short hill that I can really power up.
- I also consider standing up coming out of a tight corner where the importance is to get your bike back up to speed.
- Don't aim for absolute even power.
- When you encounter hills or headwinds increase your power output appropriately (this varies depending on if it's a 20-second hill or a 2-minute or 20-minute hill) to even out the speed distribution instead.
Strength training and cycling
Benefits of combining strength training and endurance training vs. endurance training alone for performance. Reprinted with permission - Click to zoom
- Research shows that strength training is important for all endurance athletes for injury prevention and overall health.
- The old theory of strength training is you can just do it on the bike by riding at 50 rpm all winter long. This does not have a huge amount of strength training benefit. It just gets you used to riding at 50 rpm.
- In the gym, the studies that have been done combining both endurance training and heavy strength training shows there is a mutual benefit. There is an improvement in power.
- This is due to changes in your neuromuscular patterns and your movement efficiency. You’re able to recruit different muscles. This leads to less overall fatigue in particular muscles.
- Core work is very important for spending an extended time in an aerodynamic position during cycling. You need to have a very strong core in order to have this whole link in the body that allows you to transmit power through to the pedals.
- You need to periodize the strength training. You’re not going for the bodybuilder look. You’re also not just doing the same thing throughout the entire year.
- During the off-season, you can focus on strength-based work. Whereas, as you get into the competitive season, it’s more about maintenance and building bike specific power.
- This is not something that you will be doing the entire year. You will be doing it in the off-season and build up to it gradually.
- To start with, you’ll be doing a lot of general body conditioning exercises to get you used to the higher weights.
- After that, keep in mind that most of the initial changes during the first 2-4 weeks in terms of the amount of weight you can lift aren't because of muscle changes, it’s because of neural changes. You’re able to recruit more muscle fibers from different muscles.
- Then, during the 4th-6th week, this is when you would want to hit the muscles with that max, high-level strength work to build as much muscle strength as possible
- Then after that, you would want to taper that down to get to more cycling, running, or swimming specific exercises that are going to resemble what you’re actually doing on the bike, run, or swim.
What’s the role of plyometric exercises?
- If you don’t have access to a top level gym with all the savvy Olympic weight equipment, you can do a lot with just plyometrics.
- Most of it depends on what you like to do and on what you have access to.
- Plyometrics may have a lesser role in non-drafting races where it’s more about that steady, sustained muscle strength. This is where the traditional type, higher weight training is useful.
- If your emphasis is more on draft legal ones where there may be a lot of acceleration and power bursts, this is where plyometrics play a big role to teach your body how to instantly develop power.
How do you order your workouts if you have both endurance and strength training on the same day?
- This depends on the phase of the year that you are in. If you’re in the off-season where your focus is on heavy weight training, that should be your priority and emphasis.
- So in this part of the season, do strength training first when you are most fresh.
- There's overwhelming evidence of the benefits of strength training for endurance performance.
- Heavy strength training and plyometrics can both be beneficial. Heavy weights are more specific for non-draft, steady-state races and plyometrics for draft-legal racing with high power variability.
- You must periodise your strength training.
- You cannot do strength training on the bike by riding at low cadences in high gears.
Favourite book, blog, or resource related to cycling or triathlon:
Favourite piece of piece of gear or equipment:
A person in cycling, triathlon, or science that you admire:
- Steve Bauer - former professional road cyclist
Links, resources and contact
Links and resources mentioned
Connect with Stephen Cheung
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Hi! I'm your host Mikael,
I am a full-time triathlon coach and an ambitious age-group triathlete. My goal is podium at the Finnish national championships within the next few years.
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