A 2012 YouTube clip shows a Liquigas-clad Ivan Basso riding up the 9.8km-long Volterra climb just outside Tuscany. On the saddle, at less than 50 rpm, Basso pushed a massive gear, and he rarely ever stood. He was performing an SFR (slow frequency revolutions) workout, an aerobic strength training workout believed to build leg strength and overall efficiency. Cycling lore says that Basso’s SFR workouts consisted of eight reps of three minutes at 380w and 45rpm, or 115 percent of his FTP – an incredibly low cadence at a very high power output, even for such an experienced rider. My knees hurt just thinking about that.
Despite his cycling success, recent research shows that Basso’s SFR workouts have no strong scientific basis. Countless coaches, riders, and programs have endorsed the benefits of SFR’s over the years: increased leg strength, aerobic capacity, cycling performance, and pedaling efficiency. Heck, I do them myself.
But while the practice makes sense, at least in theory, there is currently no scientific evidence showing that low cadence intervals, ‘big-gear,’ or ‘on-the-bike strength work’ will make you a faster cyclist. In fact, many studies have shown that performing intervals of the same intensity and duration at a freely chosen cadence instead, are “beneficial for performance and physiological adaptations.”
For some, riding at low cadences can do more harm than good. Cadences below 70rpm, and especially below 50rpm, place a high amount of torque on the muscles and joints of the lower body. The knees, in particular, are in a high-risk position during SFR intervals, as any tiny imbalances in bike fit or pedal stroke can quickly manifest into a serious overuse injury.
Where did the myth of low-cadence training come from?
In the old days, cyclists didn’t go to the gym and lift weights. In fact, many cyclists nowadays still don’t. But the trend is shifting, and in the positive direction too. As more and more cyclists hit the gym, they are realizing the benefits of strength training: Increased strength and flexibility, improved cycling efficiency, and chronic injury prevention.
The logic behind SFR intervals is this: You push harder on the pedals, therefore your legs get stronger. But scientifically supported evidence is sparse. While some studies cite increased muscular strength and overall cycling efficiency as a result of SFR intervals, these improvements have been shown to be no more significant than in the control group who saw improvements simply by following a structured training plan and performing the intervals at freely chosen cadences.
The science isn’t all bad, however, as one New Zealand study may have found support for low cadence interval training (Paton, et al, 2009, “Effects of low- vs. high-cadence interval training on cycling performance”). However, this study consisted of only 18 total participants, lasted just four weeks, and contained no control group. While the differences between the low-cadence and high-cadence groups were significant, even the authors admitted that there may be more at play than the training alone, stating that, in regard to the differences in mean maximal oxygen uptake, “differences for other physiologic indices were unclear. Correlations between changes in performance and physiology were also unclear.”
Cycling is a lot more complicated than just pushing hard on the pedals. In order to be fast, you need to produce a high watts-per-kilogram output (in a fast, aerodynamic position, etc.) for a long period of time, and you also need to be smart, efficient, tactically savvy, and psychologically strong. While SFR intervals may improve your power output at 50rpm, science has yet to prove that they would improve your ability to sprint, time trial, climb, or attack.
In general, pedaling slowly only makes you better at one thing: pedaling slowly.
The ideal cadence for cycling
Science suggests that there is no ideal cadence for cycling. Sorry, that’s probably not the answer you wanted to read. What research does suggest is that ideal cadence varies between individuals, so finding your ideal cadence may be easier than you think. In fact, you probably already know it – it’s whatever comes naturally to you.
When you’re pedaling along, when your head gets lost in the clouds, and when you’re not even thinking about your cadence… that is your ideal cadence. It works for you, and that’s all that matters. If your coach prescribes a “high-cadence intervals” session, ask them what numbers you should shoot for. What is defined as “high cadence” will vary greatly between individuals. For a novice rider whose natural cadence is 80rpm, holding 100rpm for five minutes could be a challenging high-cadence interval. For an experienced track rider, on the other hand, a goal of 130+ rpm is more suitable; 100rpm is their warm-up pace, after all.
The case for SFR intervals
Weight lifting – and other forms of strength training such as powerlifting, circuit training, and plyometrics – is safer and more effective than SFR training when it comes to improving muscular strength and explosive force. Structured gym workouts may better isolate certain muscle groups with less risk of doing damage, and come with less risk for chronic injury compared with doing SFR intervals on the bike.
Some coaches — myself included — prescribe SFR intervals to their clients as a way to both change up the routine and activate cycling-specific muscles that have been trained in the gym. For example, the vastus lateralis muscle of the thigh, and the gluteus maximus muscles of the backside, can be specifically trained using front squats and deadlifts, respectively. In order to transfer these strength training gains to cycling, coaches often prescribe SFR or low cadence intervals to activate those same muscles in the cycling pedaling position. Despite the promising muscle activation crossover, science is yet to determine if this practice actually improves cycling performance.
It is also beneficial to practice SFR or low-cadence intervals in case you find yourself under-geared on a steep climb, or powering out of a sudden stop such as in a cyclocross or mountain bike race. We’ve seen similar scenarios at the highest level of cycling in the Vuelta a España — sometimes there simply aren’t enough gears to pedal up a climb at 90rpm, and it’s better to be prepared to pedal at 50rpm than give yourself a knee injury because you were ill-prepared. That said, it is generally both safer and more feasible to practice power starts (e.g. 15-second over-geared sprints) rather than long, low cadence intervals.
In summary: Unless the year is 1963 and you’re riding a Heylett Speciale up l’Alpe d’Huez in the 45-tooth “little ring”…there’s no need to practice riding at 50rpm for thirty minutes at a time.
Effects of Cycling Training at Imposed Low Cadences: A Systematic Review (Hansen and Rønnestad, 2017) https://www.ncbi.nlm.nih.gov/pubmed/28095074
Low cadence interval training at moderate intensity does not improve cycling performance in highly trained veteran cyclists (Kristoffersen et al. 2014) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3907705/
Load and velocity of contraction influence gross and delta mechanical efficiency (Sidossis and Horowitz, 1992) https://pubmed.ncbi.nlm.nih.gov/1521959/
Gross efficiency during flat and uphill cycling in field conditions. (Nimmerichter et al. 2015). International Journal of Sports Physiology and Performance. https://pubmed.ncbi.nlm.nih.gov/25611890/
Effects of low- vs. high-cadence interval training on cycling performance (Paton et al. 2009) https://www.ncbi.nlm.nih.gov/pubmed/19675486
Muscle activation during cycling at different cadences: effect of maximal strength capacity. (Bieuzen et al. 2007) https://pubmed.ncbi.nlm.nih.gov/16996277/
1963 Heylett Speciale http://classiclightweights.net/france/helyett/1963-helyett-speciale/
Ivan Basso YouTube video: https://www.youtube.com/watch?v=RQweKmTTTww