By Rick Schultz
Below is an interview conducted with former pro cyclist, Duban Sanchez. Duban stopped by one day wanting to discuss a bike fit to help mitigate knee pain.
BFC: Good morning Duban. I’ve been receiving lots of questions regarding shorter crank arms. I would like to discuss with you your experience with shorter cranks but first, I would like to give a brief history.
BFC: To get started, can you tell us how tall you are and what is your inseam?
DUBAN: I’m 5’6 and my inseam is 31
BFC: I believe you started with Team Velosport? Jeff Shein’s junior development team based out of Irvine, California? I only hear great things about that team.
BFC: I know Jeff has put together a great program for juniors. How many years did you stay with team Velosport, and how old were you?
DUBAN:I first became a part of the program in 2013, when I was 17, this was my last year as a junior and I knew Jeff because i did some racing along his son Michael. This was also the first year the team had an elite program. I was also a part of the programs in 2015 as a u23 rider, and in 2018 just as a recreational rider and a mentor.
BFC: What was your next opportunity? Was it KHS-Maxxis Pro Team?
DUBAN: Yes sir. Actually Robert Freeman (Velosport rider too) and I went to KHS after having a great season in 2016
BFC: How many years did you stay with them, and what was the reason you left?
DUBAN: I unfortunately stay with them just one year, 2016. This was due to the fact that at the end of the year the team joined with Elevate pro team and I didn’t make the cut.
BFC: You mentioned that you stayed off the bike for about a year?
DUBAN: On and off, yeah. At the end of 2016, just before I got word that I didn’t make the cut, I got a bad knee problem that forced me to get off the bike for 4 months. I got back on the bike, but it was a couple of weeks before I had to get off again. It was almost toward the end of 2017 when I was able to ride again, but I couldn’t do it for more than 3 consecutive weeks, as the pain came back.
BFC: About a year ago, you came to visit us at the home-studio as a referral from Jeff Shein? What prompted the initial visit?
DUBAN:All started at the end of 2016 when I was going home from a big ride, I got a sharp pain in my knee, I actually was only able to pedal with my left leg for the last mile. At first I thought it wasn’t a big issue, but I quickly notice that it was, since I couldn’t ride without pain anymore. I went to my school’s sports department and they helped me a lot. They found that I had a muscle imbalance, my quads were too big and tight while my glutes were too weak. This imbalance forced my patella to track incorrectly. I went 3 times a week for 6 months for PT.
BFC: My daughter, who is also a PT says the same thing — that all cyclists have either tight muscles or weak muscles. Why? Because they don’t stretch, nor do the right strength exercises. You are correct, she says it’s all about muscle balance.
Just FYI, several years ago, I did a bike fit on a national level criterium racer. By national level, I mean he was on the podium at Nationals. To prove to him that his quads were tight, I had him do the Thomas test (see picture to the right). The Thomas test is designed to test for tight iliopsoas (hip flexor), rectus femoris (quadriceps), tensor fascia latae/IT band and biceps femoris (hamstring). His quads were so tight that his affected leg (leg being tested) stood straight out – see B. Ideally, the affected leg should look like A; i.e., bent 90° at the knee. We always try and get the cyclist to stretch as well as to put together a balanced strength program for them.
BFC: Continuing on, you brought in a Trek Madone to be fit. I remember that the fitting took several weeks, only because we needed to make numerous changes. First, we adjusted your cleats but, when we started looking at saddle height, the seat mast that was on the Trek was the short one – the one that Madones’ normally come with. In fact, it was WAY too short. You located a longer version that had the same offset and then brought everything back the following week. If I remember correctly, we ultimately raised the saddle somewhere between 5-6cm. This put your knees at a max extension of around 150 degrees. But, when we measured your knees at max flexion, they were well into the RED zone. When we looked at the crank arms, they were 170mm. Those along with 172.5mm is what I see on most framesets from 50cm-56cm.
BFC: What size was your Madone frame?
DUBAN: It’s a 52cm (and it had 170mm cranks)
BFC: We then put you on the bike sizer. Do you remember what crank arm length was ideal for you?
DUBAN: yeah, 165mm
BFC: So, we went from 170mm to 165mm. You came into the studio with severe knee pain then, a week later, raced the Manhattan Beach Grand Prix Pro/1/2. Recently, you placed 12th in another pro race. What were your initial thoughts about shorter crank arms?
DUBAN: It just felt weird at first, but I quickly got used to them, especially when I was in the drops, because my legs weren’t hitting my stomach.
BFC: About half of the clients that come in have severe knee pain and are looking for a solution and relief. Everyone of them are riding crank arms that are WAY too long for them.
BFC: Most clients are hesitant to use shorter crank arms. Their reasons are numerous but one stands out as the most frequently stated – I will lose leverage and ultimately lose power.
BFC: Duban, you have been riding shorter cranks for about a year now. Tell the readers how long it took you to get used to them. Did they feel natural or unnatural?
DUBAN:I would say it took me about 1-3 rides to get used to them, it just felt like it was easier to put the power down while taking a lot of pressure away from my knees. Actually, the other day I rode a gravel bike and it had 170mm cranks, and I quickly noticed the difference, it didn’t feel comfortable at all.
BFC: Did you lose any power with shorter cranks?
DUBAN: Not at all.
BFC: What about knee pain?
DUBAN: It went away. Right away, I noticed that I didn’t have the same pressure on my knees. After a couple of weeks I began to do some climbing and notice that I wasn’t sore the next day, and that I was even able to ride two big days in a row.
BFC: Anything else that you might mention that would convince the readers to use or at least investigate shorter crank arms to help alleviate knee pain?
DUBAN: I always like to keep a high cadence, and using this size of shorter cranks has really helped me with higher cadence. I am now able to spin the cranks easier, especially when the speed is super high and I’m on the lower gears [like in crit racing].
BFC: One last thing I would mention is for the readers to contact their Physical Therapist or Doctor is they have any medical questions. I know PTs have knee strengthening exercises and can conduct a real evaluation to see how damaged the knee actually is.
BFC: I also recommend the readers if you have knee pain, get it checked out ASAP because it will only get worse. Please don’t risk permanent knee damage.
BFC: One last item, it has been my experience that shorter crank arms also help to alleviate hip pain. Duban, any last words?
DUBAN: Another cool thing is that I never clip the ground anymore!! 165mm + speedplays= pedal through every corner. Thanks for your help Rick!
BFC: If any of the readers have any questions, please don’t hesitate to email, text or call us at Bike Fitness Coaching.
I had this same issue, a sudden sharp pain then almost a year of pain. Taping & stretching helped a little, so did more rest and a higher cadence. Just recently I switched to 172.5mm crank arms from 175mm and this helps too. I’m 54, 5’11” 185lbs on a 56cm frame. At my age I MUST spin more and it has become a real struggle as I am a masher, but its the best, cheapest and easiest solution. I will persevere. Good luck to all.
Very interesting article. I’ve started to develop knee pain lately at 54 years old. I have been seriously riding a road bike since 1984 and switched into triathlon in 2006. Never had knee pain until two years ago.
I’m pretty sure I originally damaged my knees by doing a lot of flooring work on an old house in 2018. Squatting down and standing a lot over a few months seemed to over stretch the patellar tendon too much. This is the same pain that has been coming and going. I continued to ride and run while working on the house. The knee pain showed up when running as a sharp patellar tendon pain that would immediately stop you running. But after walking a bit you could start up pain free. I’ve never felt any bone on bone pain. Also, since I run more often than ride now I don’t think I have the muscle imbalance concerning hamstring/quadriceps that was described.
Went to a doc who took x-rays and saw nothing wrong and knees looked good with no signs of early arthritis. Did PT for a few months and they could find nothing wrong. Nobody could figure out why my knees were not healing. Eventually I discovered I was low on Vitamin D, which helps in the healing process. Spending more time in the mid-day sun and taking a supplement and the knees felt great for a while. Also the house work was completed. Almost PR’d a half marathon last fall. Now my knees are sore again. With covid I haven’t been in the pool since mid-March so my “joint therapy sessions” are gone. I’ve also been riding a lot more with no swims in the schedule. This extra riding I believe has also started me into some new hip pain on one side.
I ride three bikes regularly – a TT bike, a road bike and a mountain bike. The TT and Road bike have the same saddle and crank length – 172.5. I use the same shoes with both. I noticed recently that the TT bike seat had slipped down a little and was causing knee pain. I raised it back up to the same height as the road bike and that felt a lot better. My mountain bike has 175 cranks but I only ride this a few times per month. These three bikes have a pretty wide seat angle ranging from very relaxed on the mountain bike to pretty steep with the TT bike that has a forward seat post.
Now after reading this article I’m wondering if my cranks are too long. I used 170 cranks from 1984 – 2005 and then moved to 172.5. I am a high cadence rider usually 90-100 rpm. I am 5’10”. My road bike is a 56 cm. I tried to measure my inseam which is difficult to get a precise measurement. It is somewhere between 31-33” with no shoes. Pant sizes are no use as each brand fits differently and you find that what fits from one brand to the next never has the same inseam measurement.
Referring to the article, I am a little confused by the part about Duban’s bike fit details. It says that the saddle height was set for a max extension of about 150°. But that then the max flexion was into the red zone. I assume this means at top of the pedal stroke the knee was bent too far. What angle range is too much flexion? And, honestly, how do you measure this without a video camera and a computer to overlay angles onto the leg bones? Also, wouldn’t it make a difference about how long your femur and tibia are (ratio)? This may effect whether your legs hit your stomach.
In the end I am not sure my knee pain is related to crank length but I would love to get rid of it! How would you find the required type of bike fitting equipment needed to figure all this out? What specific type of equipment would you ask for?