David Romanowski commented on my Cycling over 60 (or over 70) post. He stated that he personally strives for a cadence in the neighborhood of 90 when touring. After giving that a try on my training rig and having some difficulty, I decided to research the topic.
Cadence is the count of the number of complete revolutions of the chain wheel per minute. To measure cadence you can purchase a cadence sensor or count the number of times a pedal reaches a specific point in the stroke. For example, if I want to use the motion of my right foot to count cadence, I will count the number of times per minute that my right foot reaches the bottom of the stroke.
There is a simple formula that expresses the relationship between cadence and two other important factors in cycling: power = force x cadence. This says that the same power output is achieved by either high pedal force and low cadence or by low pedal force and high cadence. The formula tells me that on a tour where endurance is important I want to achieve a constant, sustainable power output, varying the force on the pedals and the cadence to achieve that output. My personal experience doesn’t contradict the formula.
My training rig does a good job of simulating conditions of cycling on a flat surface by providing adequate resistance for the rear wheel. I couldn’t get to a cadence of 90 and the best that I could sustain for any length of time was in the 70s. My comfort level is below that in the 60s. I can maintain the 60s for hours. If I were on a tour and geared down to sustain the 70s, I wouldn’t be going very fast. In the 60s, I can do between 15 and 18 miles per hour on the flats in the earlier hours of the day. In the 70s, that would drop to 13 to 14 miles per hour since I would need to gear down unless I want to output more power. If I gear up and try to sustain the 70s, I would still be mashing the pedals with more force to keep up the pace and I would become exhausted sooner. I experience a positive change in my performance as I increase the cadence in the effort to go fast, but it is short lived. The strategy works in a sprint, for example, up a short hill or passing a gaggle of riders. At the end of the sprint, I feel the burn. On long hills, I’m better off in the 60s and geared as low as needed to sustain my cadence.
The physiology of cadence is interesting, but doesn’t give you any actionable information. There are different muscle fibers that are employed by your body at high cadence rates than at low rates. It still falls to you to determine the rates that are best for you because there is no magic cadence. If you are mashing the pedals up a hill, you will discover the low rate fibers by the burn in your thighs. If you have enough range in your gear set, you instinctively shift down and increase your cadence to avoid the burn. If you are spinning on the flats and making good time, the high rate fibers are doing their job. With a paved surface or a tail wind it may be possible to shift up a gear and keep spinning. I don’t need to know the physiology to make those things happen. I do need to understand the basic power, force, and cadence relationship.
There is some consistency on the Internet in the topic of cadence. The trouble is that most discussions approach the topic from the point of view of a race or triathlon. For a race or triathlon the objective is speed for a short amount of time as opposed to the endurance needed by a touring cyclist.
Coach David Glover offers what I consider the best answer to the question of proper cadence in his YouTube video. His recommendation: use whatever cadence you use in training or between 60 and 80 revolutions per minute for amateur or recreational athletes. On the road on tours, I have rarely seen fellow bicycle tourists cranking along at rates of 80 or greater. That doesn’t mean that a cadence of 90 is bad; it means that it is not for everybody. The Global Cycling Network did a non-scientific experiment, also shown on YouTube, which you can do at home except for the part where blood is drawn. This provides another answer: the ideal cadence is the one at which you are most comfortable.
Those of us who tour need to keep this in mind as we train. We need to train at the cadence that will be optimal for each of us individually. During training one personal goal for me is to set a target cadence that I can sustain for 50 to 70 miles per day for seven days or more. That done, the most important thing to do on the road is to be changing gears to account for changing conditions and grades to be able to sustain the target cadence. One of the changing conditions that I experience is that I get tired toward the end of the day.
Personally, this is a satisfying result since it fits all sizes. The summary: do the cadence that feels best for you. Intuitively, I felt that I was in the correct zone with my personal cadence in the 60s. There is no magic, effortless cadence. You will always need to exert force on the pedals to keep moving, sustain a cadence, and make progress on the trail. For a bicycle tourist, there is a balance that is required to achieve endurance and that balance of factors is likely different for each of us.
By the way, I wouldn’t waste your money on a cadence sensor. Measure your cadence using a watch. It won’t take long for you to determine your comfort zone and to be able to judge it by the way you feel.