One bike adjustment for the most efficient pedaling power

Why is an updated bike fit sometimes not enough? How is it possible for you to undergo top-of-the-line pressure mapping and motion analysis with a good bike fitter, and yet you are you still not in the most optimal position on your bike? And how can fluctuations in your bike set-up influence your pedaling efficiency? Well … you are about to find out!

As an endurance coach, I'm a great believer in data. And that everything that can be measured can be improved. This can (and honestly should) be applied to everything related to endurance sports. Your diet, your power, your performance on the bike and, without a shadow of a doubt, your bike fit as well. So, with the same mentality, I've who was about to come back after two years off the bike after having a child.

Cycling in training camp after two years off the bike after having a child.

ATHLETE BACKGROUND

To give you a brief insight into her background:

  • Over her career she has won several national championship titles: 3x TT, 2x XCM, 1x XCO
  • She has been ranked No. 5 in the world in XCM ranking
  • Finished 12th in European Championship in XCM
  • Raced semi-professionally in Belgium for 3 years
  • Won Belgian regional championship two times

So she was quite an accomplished rider by the time she had her first child. Coming back after two years almost entirely off the bike is a tough task because there are a lot of variables that have changed and need to be taken into account. Her goal was to race time-trial nationals with the bold intent of winning it. And if everything went well, then she would race the European Championships and maybe something else.

“Her goal was to race time-trial nationals with the bold intent of winning it.”

At the start of the year, we sat down to map out the training plan for the whole racing year. That is not very typical, because I usually do it as soon as the current season has come to a close, but this time was a bit more special. One of the big things to take into account was her bike fit. After having a child, a woman's body is subject to change, and she was no exception. We had to find an appropriate saddle, change her shoes, swap the cranks for shorter ones, and just let her be comfortable on the bike.

 

ADVANCED BIKE-FITTING

LEOMO TYPE-R motion analysis sensor on road cycling shoe.

We had planned on a big build training block where she was supposed to go for a training camp for four weeks. Briefly, before that, I managed to find an excellent fitting specialist in Berlin, who used a 3D motion capture system as well as a pressure-mapping system. All this and excellent credentials would serve as a good basis to have an appropriate bike fit. She flew to Berlin with her bike so it could be assessed and adjusted by the fitter. After four days she returned with a new bike fit, new saddle and new insoles, and a good feeling about how it all came together.

Bike Academy Berlin fitting session.

“The saddle was right, insoles were working great, and the overall feeling was on par with that."

Using the best-in-business pressure-mapping system on the saddle and in the insoles of the shoes, the fitter was able to clearly identify that she was sitting too high. She was producing the most significant power in her pedal stroke at the bottom of it (in about the 5 o'clock position), which is sub-optimal, to say the least. By lowering her saddle considerably was able to make significant changes, and she was producing the biggest power at her 1 o'clock in no time. Everything was measured and evaluated, so everything should be excellent, right?! Nope or not entirely. After about a week she took off and went to Spain for a training camp. As almost all the sessions before that were done indoors, this was the first time we could see how the new bike fit worked in real-world conditions. The saddle was right, insoles were working great, and the overall feeling was on par with that.

DEAD SPOT SCORE PROBLEM

Almost straight from the get-go, we started to use LEOMO TYPE-R. The first week was just to collect data, so no prescriptions were made to alter her pedaling style or position on the bike. Besides that, she just had to ride her bike for a bit to get used to riding it outside. I did have data from indoor sessions, but, like everything, it was not specific to what she was preparing for riding outdoors. From indoor sessions, I already knew that she had a very "clean" pedaling technique and her Dead Spot Score (DSS) was very low.

On the second week, we started to perform different tests to get good benchmark numbers.

Data from the hill climb test showed that the right leg was completely off, with an average of 31.9 DSS score. Usually, riding with a higher power helps to clear the pedal stroke because the ride is more focused on pedaling and applying constant pressure. Therefore I typically look at segments of the ride where the athlete has gone at least at his or her threshold. As you can see in her case, the difference is massive. She is "losing" power on her most important part of the pedal stroke. We need to take into account that the DSS profile can be different for one rider when an athlete is climbing or riding on the flat. Even on a relatively simple and long endurance ride, her numbers were bad. It was obvious something needed to change.

Looking at this and other similar rides, it was clear that when she "soft-pedals" or is riding below her threshold, her right leg is producing more DSS than her left leg. It gave a clear hint that the body was self-adjusting at more significant power outputs and become as economical as possible. But DSS scores from longer endurance rides and the point of the pedal stroke where they occurred showed that the problem was current and probably in her saddle height.

How much difference can 5mm make?

After about a week of riding, I suggested that she make slight changes to her current saddle height to see how this would effect her performance data. She raised her saddle exactly 5mm without changing anything else. 

“We would need to play around the saddle height to find where she is most effective in her pedal stroke.” — Coach Janis

Even when we look at the whole set of training data and not just the part that has a higher power, the picture has changed dramatically.

DSS score for the whole ride has gone down to 0.9 for left leg and 1.0 for the right leg. Besides that, with this small tweak, we ware able to change the allocation of dead spots. Now there are more inline of the baseline we had at the beginning. In her case, we would need to play around with the saddle height to find out where she is most effective in her pedal stroke. In the future, this will come in very handy when she starts to ride her TT bike, where DSS will have to be optimized as well as her and torso and hip angle.

Takeaway

  • LEOMO is indispensable for verifying an athlete's bike-fit position outside in a real training environment or even in a race.
  • Saddle height uses static fitting and even when using pressure mapping can lead to a significant DSS when riding outside or when in the racing position, therefore LEOMO can play an important role when it comes to fine-tuning one's bike fit.
  • LEOMO TYPE-R can be used for injury prevention and not only for increasing performance. I'll talk about this in my next blog post.

Be sure to head on over to Train2win and check out their services. Also special thanks to TRAIN2WIN head coach Janis Musins 


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