Running cadence is the number of steps taken per minute. There is an increasing trend for runners to shorten the stride length and increase the rate that the legs turn over (ie increase cadence). With many claims and dogma along the lines that if you can get the cadence to around 180 steps/minute then this is somehow a magical way to reduce the risk for injury and increase performance. As usual, there is no evidence to support that.
The initial interest in this was popularized by the coach Jack Daniels (who was described by Runner’s World as the “World’s Best Running Coach”) with most people advocating this approach referring to Daniels comments on this (see the Appeal to authority fallacy).
Others have done a much better analysis of this than I could: Steve Magness (180 isn’t a magic number- Stride Rate and what it means); Alex Hutchinson (The problem with 180 strides per minute: some personal data); Pete Larsen (Running Speed: Human Variability and The Importance of Both Cadence and Stride Length); and Peter Dunne (Running Cadence and Recent Research). I previously started a discussion on it here.
I think they all agree that it is a magical mythical number and there is a lot of individual variability. Increasing cadence does seem to have benefits in terms of preventing overstriding.
A couple of studies have looked at cadence manipulation:
Effects of step rate manipulation on joint mechanics during running.
Heiderscheit BC, Chumanov ES, Michalski MP, Wille CM, Ryan MB.
Med Sci Sports Exerc. 2011 Feb;43(2):296-302.
The objective of this study was to characterize the biomechanical effects of step rate modification during running on the hip, knee, and ankle joints so as to evaluate a potential strategy to reduce lower extremity loading and risk for injury.
Three-dimensional kinematics and kinetics were recorded from 45 healthy recreational runners during treadmill running at constant speed under various step rate conditions (preferred, ± 5%, and ± 10%). We tested our primary hypothesis that a reduction in energy absorption by the lower extremity joints during the loading response would occur, primarily at the knee, when step rate was increased.
Less mechanical energy was absorbed at the knee (P < 0.01) during the +5% and +10% step rate conditions, whereas the hip (P < 0.01) absorbed less energy during the +10% condition only. All joints displayed substantially (P < 0.01) more energy absorption when preferred step rate was reduced by 10%. Step length (P < 0.01), center of mass vertical excursion (P < 0.01), braking impulse (P < 0.01), and peak knee flexion angle (P < 0.01) were observed to decrease with increasing step rate. When step rate was increased 10% above preferred, peak hip adduction angle (P < 0.01) and peak hip adduction (P < 0.01) and internal rotation (P < 0.01) moments were found to decrease.
We conclude that subtle increases in step rate can substantially reduce the loading to the hip and knee joints during running and may prove beneficial in the prevention and treatment of common running-related injuries.
It was a good study and the only issue I have is that “We conclude that subtle increases in step rate can substantially reduce the loading to the hip and knee joints during running and may prove beneficial in the prevention and treatment of common running-related injuries“. No one has actually shown yet that reducing the load or rate of load can actually prevent injury. That is pure speculation.
Step Frequency and Lower Extremity Loading During Running
Hobara, H.; Sato, T.; Sakaguchi, M.; Sato, T.; Nakazawa, K.
Int J Sports Med 2012; 33(04): 310-313
The purpose of the present study was to ascertain whether increase in step frequency at a given velocity during running reduces the lower extremity loading variables, which is associated with tibial stress fracture in runner. We hypothesized that the lower extremity loading variables at a given speed would be minimized at around + 15% f step. 10 male subjects were asked to run at 2.5 m/s on a treadmill-mounted force platform. 5 step frequencies were controlled using a metronome: the preferred, below preferred ( − 15 and − 30%) and above preferred ( + 15 and + 30%). From the vertical ground reaction force, we measured following lower extremity loading variables; vertical impact peak (VIP), vertical instantaneous loading rate (VILR) and vertical average loading rate (VALR). We found that there were significant differences in lower extremity loading variables among 5 step frequency conditions. Furthermore, quadratic regression analyses revealed that the minimum loading variable frequencies were 17.25, 17.55, and 18.07% of preferred step frequency for VIP, VILR and VIAR, respectively. Thus, adopting a step frequency greater than one’s preferred may be practical in reducing the risk of developing a tibial stress fracture by decreasing lower extremity loading variables.
This study was more measured in its conclusion: “Thus, adopting a step frequency greater than one’s preferred may be practical in reducing the risk of developing a tibial stress fracture by decreasing lower extremity loading variables“, as tibial stress fractures (which make up ~4% of running injuries) are the only injury that has been linked to impact loads.
A third unpublished study presented at the APTA conference in January 2013, found that “A 5% increase in cadence resulted in runners experiencing, on average, 3.4% less time in contact with the ground during each foot strike. This resulted in 2.2% lower heel loading and 2.2-2.4% lower forefoot loading over time” and concluded that “Increasing cadence by 5% in healthy runners decreases plantar loading associated with lower extremity injury“. This study was on plantar pressures and I do not know of any injury that is associated with a high plantar loading!
As always, I go where the evidence takes me until convinced otherwise and increasing the cadence is not going to be a magical panacea for reducing injury.