What does the evidence show?
What does the evidence show?
In the wake of Mo Farah’s stunning double gold-medal performance at the 2012 London Olympics, running fans were eager to learn the secret. How had he gone from also-ran to champion after joining Alberto Salazar’s Nike training group in Oregon? One answer that soon gained currency: He hit the weight room with a vengeance.
“Now he is not just a skinny guy, he’s a strong wiry guy,” Salazar told the Guardian’s Sean Ingle in 2013. “And he’s not gained more than a pound or two despite lifting heavy weights for power. People have always thought distance runners should lift light. Don’t you believe it.”
Since then, numerous other (and sometimes less savory) explanations for the success of the Farah-Salazar partnership have been suggested. But the idea that serious, meathead-style strength training can boost running performance has stuck around. Compared to a decade or two ago, there’s far more talk among runners about squats and deadlifts and other powerlifting staples. They’re supposed to make you faster, more powerful, more efficient, and less injury-prone.
For those of us wondering how to incorporate strength training into our own routines, two key questions stand out. First, what sort of strength training do top runners actually do? And second, does it really work? Happily, two recent studies by a group of researchers in England, led by Rich Blagrove of Birmingham City University, seek to answer exactly those questions.
The first study, published last fall in the Journal of Strength and Conditioning Research, was simply a survey of 667 distance runners, ranging from locally to internationally competitive, about their use of strength and conditioning exercises. The most common activities were stretching (86.2 percent of runners reported doing it), followed by core training (70.2 percent), resistance training (62.5 percent) and plyometric training, which involves explosive movements like jumps to develop the neuromuscular system (35.1 percent).
What was interesting was the motivation runners reported for their strength and conditioning routines. There were two main answers: reducing injury risk (63.1 percent) and improving performance (53.8 percent). But the survey didn’t detect any relationship between strength and conditioning training and injury history in the runners. A survey like this can’t really say for sure, but—in keeping with the findings of dozens and dozens of previous studies—there was no obvious sign that diligently doing your stretches and drills prevents injuries. Instead, the key predictor of injury was training volume. The more you run, the more likely you are to get injured.
The data on performance was more intriguing. Here there was a definite pattern, where the best runners were significantly more likely to report doing strength training and plyometric training than their less accomplished peers. The arrow of causality could point in either direction: Maybe strength training makes you faster, or maybe faster runners are more likely to join serious clubs with experienced coaches who prescribe strength training. But the second study, a massive systematic review of the effects of strength training on running performance, recently published in Sports Medicine (full text freely available here), offers some convincing evidence in favor of the first scenario.
Let me cut right to the chase and say that on the basis of a detailed analysis of 24 high-quality studies, the review concludes that strength training is “likely to provide benefits to the performance” of runners. Importantly, all the subjects were trained runners; studies involving random “recreationally active” college students were excluded, because pretty much anything improves performance in newbies. There are a ton of details and nuances in there, so I’ll just highlight some key questions addressed.
The general pattern in the studies suggests that strength training improves running economy, maximal sprint speed, and time trial (that is, race) performance. Running economy is a measure of efficiency, which probably gets better not as a result of bigger muscles, but from “neuromuscular” improvements in how the brain recruits the muscles you already have. It’s also possible that strength and plyometric training make your tendons stiffer and springier, in turn making your stride more efficient. Sprint speed probably also improves thanks to neuromuscular factors. Together, the sprint speed and efficiency gains are what allow you to race faster.
The size of the improvement varies, but the approximate range was 2 to 8 percent for running economy, 3 to 5 percent for race performance in middle-distance events like the mile, and 2 to 4 percent for long-distance races like 10K.
One thing strength training doesn’t seem to do for runners is turn them into big, buff meatheads. The vast majority of studies found absolutely no change in muscle mass or size after up to 14 weeks of training. In some ways, that’s a bummer. But as Salazar noted, fear of bulking up is one of the main reasons runners have avoided serious strength training. That fear appears to be unfounded, perhaps thanks to the molecular interference between strength and endurance training.
Even though the subjects in the studies were all trained runners, most didn’t have much strength-training experience. And that’s a problem, because, as the authors note, “in less strength-trained individual…any novel [strength training] stimulus is likely to provide a sufficient overload to the neuromuscular system to induce an adaptation.” In other words, for scrawny distance runners, pretty much any type of strength training seems to work—heavy weights like Farah started lifting, light weights lifted explosively, plyometric jumps. That makes it hard to know what’s best in the long term.
Common strength-training exercises used in the studies were barbell squat, deadlifts, step-ups, and lunges. For plyometrics, studies used drop jumps from a box that’s eight to 12 inches (20 to 30 cm) high, skipping, and hopping.
For practical purposes, the authors suggest incorporating different types of strength training at different times of the year, moving between different blocks of training. This way, you’re throwing a new stimulus at your muscles once in a while instead of getting used to the same thing.
We’re drifting away from “science has proven” and getting into “here are some reasonable ideas.” With that caveat, the authors suggest that strength training two to three times a week is sufficient to see gains, and once a week is sufficient to maintain those gains. So, they advocate at least ten weeks of strength training twice a week or more, then backing off to one weekly session during racing season. Ideally, do the strength training at least three hours after a hard running workout to maximize gains from both.
In terms of the actual workouts, many of the studies started with one to two sets per exercise and gradually progressed to three to six sets over the course of a few months. There didn’t seem to be any difference between lifting heavier weights for three to five reps and lifting lighter weights for five to 15 reps. Many of the studies involved lifting to failure in each set, but it might make sense to stop a rep or two before failure to give you most of the strength benefits while taking less out of you. Plyometric workouts involved a total of 30 to 60 reps at first, progressing to more than 100 after a few months.
Even with all this information, it’s tempting to want to replicate the exact routine of top runners like Farah. And hey, you can find lots of details on these routines with a little Googling—but those details aren’t particular meaningful stripped of context and applied to someone with a completely different training history. So, I think the big takeaway from these studies is that strength training helps and, initially at least, the details don’t much matter. Get out there a couple times a week, lift some things and do some hops, and you’ve got a good chance of getting both stronger and faster.
My new book, Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance, with a foreword by Malcolm Gladwell, is now available! For more, join me on Twitter and Facebook, and sign up for the Sweat Science email newsletter.