Running, like most all sports, have long-standing myths that continue to be passed down even after being scientifically debunked. As a coach, it’s important to be aware of the more popular myths, as some of your clients will inevitably bring them up.
Perhaps one reason as to why myths persist is because we humans are psychologically inclined to seek out information that agrees with and supports our pre-existing views – this is termed, confirmation bias.
Before we discuss the myths, let’s take a deeper dive into the main reasons why myths get started and persist.
Coincidence and Correlation
A build-up of blood lactate (often termed, lactic acid) results in muscle burn. The genesis of this myth is based on a 1920 study by Dr. Meyerhof. Dr. Meyerhof observed that the leg muscles of a deceased frog twitched initially when subjected to electric stimulation. However, after a while, the twitching ceased. The cessation of muscle twitching coincided with high levels of blood lactate. Thus, Dr. Meyerhof erroneously concluded that an increase in lactate causes muscular fatigue. This is an example of how coincidence can lead to correlation.
FYI – Not only is lactate not responsible for muscle burn – it’s actually a muscle fuel!
Correlation without Causation
Just because an action appears to be the result of a particular thing or instance does not necessarily mean that it is. For example, over the years, the average marathon finishing time has increased. The quick and easy reason for this is that marathon runners have gotten slower (correlation). However, after looking at the data, the real reason (causation) is that marathons have exploded in popularity and therefore unlike the early days of marathoning when only avid and fast runners participated, now runners of all ability levels participate – thus lowering average marathon finishing times.
Random fact – did you know that the rates of violent crime and murder have been known to jump when ice cream sales do? Neither did we!
Myth #1: Running is bad for the knees
There is no evidence that runners have a higher rate of knee injury than non-runners. In fact, a 2016 study out of Bringham Young University showed that markers for inflammation in the knee actually decreased after a 30-minute run.
While there has not been a lot of research on long-distance runners, it’s clear the school of thought that running is hard on the knees needs to be revised.
Myth #2: 10% Volume increase rule
From purely a mathematical point of view, this ‘rule’ makes no sense. A 10% volume role ensures that low starting volumes would increase at an ineffectively slow pace. Conversely, once a runner has reached a relatively high training volume, the 10% rule would result in the volume increases being too much.
In other words, the ‘correct’ volume increase percentage should not be a static number but rather it should change throughout a training program to ensure the volume changes are realistic and appropriate for a particular runner in respect to their goal.
A 2008 study out of the University of Groningen in the Netherlands found that there was no difference in injury rates between runners that increased their weekly mileage 10% and 50%.
Myth #3: Pronation is bad
Quite a few running stores have customers run on a treadmill to assess what type of shoe to select. After showing a customer video of their foot pronation, the employee will likely suggest some sort of stability shoe to either greatly reduce or eliminate pronation. To the untrained eye, pronation looks incorrect so it’s a no-brainer to try to eliminate it.
In reality, pronation is a natural movement that helps the body absorb stress from the impact of running and walking. While overpronation may be an issue (although there is no definitive definition of exactly what constitutes overpronation) only if it is accompanied with pain should it be considered an issue.
Myth #4: Stretch before running
Several studies have demonstrated that stretching prior to running may decrease the contractile force of muscle fibers. However, from a performance standpoint, this might most negatively effect explosive-type running such as sprinting so while it may not equate to distance running, stretching is likely not a prerequisite to running.
It should be noted that myofascial release (i.e., foam rolling) has been shown to decrease muscle ‘tightness’ while not influencing a muscle’s contractile force.
Myth #5: Weightlifting adds muscle bulk
Yes, if you eat 10,000 calories a day, lift a ton of weight and focus on one or two body parts per day, you will likely gain muscle weight. However, as this is not the strength training regimen that most runners follow, this is likely not an issue.
Myth #6: Barefoot or minimal shoes reduce injury risk
While minimalist running is no longer a new trend, the popularity of it can be traced back to Christopher McDougall’s book, Born to Run. A portion of the book profiles the Tarahumara tribe in Mexico and more specifically, it profiles members of the tribe that run long distances in little more than sandals.
This book, along with the theory that running barefoot or in minimal footwear strengthens the foot due to a lack of arch support gained traction (pardon the pun) amongst new and seasoned runners.
While there is some evidence that running barefoot or in minimal footwear can reduce the chance for injury due to runners altering their footstrike and running mechanics, this is largely a biomechanical issue, not a footwear issue. However, converting too fast to this type of running from ‘normal’ running shoes will likely increase the chance of injury.
Myth #7: Dehydration causes cramping
Dehydration and, or a lack of electrolytes have long been thought to be the main culprits of cramping. However, recent studies have shown that the primary reasons for cramping are too much intensity and, or distance – not dehydration or a lack of electrolytes.
Hyldahl RD, Evans A, Kwon S, Ridge ST, Robinson E, Hopkins JT, Seeley MK. Running decreases knee intra-articular cytokine and cartilage oligomeric matrix concentrations: a pilot study. Eur J Appl Physiol. 2016 Dec;116(11-12):2305-2314. Epub 2016 Oct 3.
Hinterwimmer S, Feucht MJ, Steinbrech C, Graichen H, von Eisenhart-Rothe R. “The effect of a six-month training program followed by a marathon run on kneejoint cartilage volume and thickness in marathon beginners.” Knee Surg Sports Traumatol Arthrosc. 2014 Jun;22(6):1353-9. doi: 10.1007/s00167-013-2686-6. Epub 2013 Sep 18.
Schwellnus MP, Drew N, Collins M. “Increased running speed and previous cramps rather than dehydration or serum sodium changes predict exercise associated muscle cramping: a prospective cohort study in 210 Ironman triathletes.” Br J Sports Med. 2011 Jun;45(8):650-6. doi: 10.1136/bjsm.2010.078535. Epub 2010 Dec 9.
Schwellnus MP. “Muscle cramping in the marathon : aetiology and risk factors.” Sports Med. 2007;37(4-5):364-7.
Rick Prince is the founder of United Endurance Sports Coaching Academy (UESCA), a science/evidence-based endurance sports coaching education company that certifies running and triathlon coaches.
To learn more about our Running Coach Certification and to get a code for $50 off, click here!