6 Common Myths About Strength Training

For runners, a little strength training can go a long way

In his new book Quick Strength for Runners, running coach and personal trainer Jeff Horowitz shows that just a little strength training can go a long way toward making runners stronger, faster, and more resistant to injury. In his 8-week program, runners spend less than an hour a week performing simple exercises that build a well-balanced, strong body for running.

Despite its benefits, some runners are reluctant to begin strength training because they believe it will cause them to bulk up with unwanted muscle mass that will make it harder to run. Horowitz busts the 6 most common myths about strength training for runners.

Republished with permission of VeloPress from Quick Strength for Runners by Jeff Horowitz.

MYTH: Strength training will make me bigger, and I do not want to be bigger. Strength training can enlarge your muscles— known as “hypertrophy”—but that is not an inevitable outcome of strength training. Think of doing strength training as using a tool: It will do what you ask of it. If you ask it to build muscle mass, it will do so. But if instead you ask it to build only lean muscle without adding mass, it will do that instead. The key is in how you strength-train.

Generally speaking, if you work against greater resistance for fewer repetitions of an exercise, you will encourage hypertrophy. Conversely, if you keep resistance moderate and perform a high number of repetitions of each exercise, you will improve strength and muscle endurance without experiencing a significant improvement in muscle size. The choice is yours. 

The strength training plan presented here is not focused on building muscle mass. In these pages you will not find such bodybuilding staples as heavy bench presses or dumbbell rows. In fact, you could have an entire strength training session without picking up a single weight.

Keep in mind, too, that you are naturally limited by your genetics and body type. If you are a lean runner who has always had difficulty gaining weight, you might not be able to put on much muscle mass even if you wanted to. The odds of you getting bulky accidentally while following a runner’s strength training plan are very low.

But what if you tend to put on weight easily? Should you avoid strength training altogether? Certainly not. That would be like throwing away the baby with the bathwater. The smarter approach is to structure your strength workouts to emphasize high-repetition exercises.

As an added benefit, the research increasingly shows that relatively low resistance strength training—the kind we are going to be talking about here—can lead to significant improvements in cardiovascular fitness. That means targeted  strength training can help improve your form and your endurance.*

MYTH: Strength training will make me less flexible. Athletes who have inelastic, overdeveloped muscles, are usually described as “muscle-bound.” They are characterized as being rigid and inflexible. This label is often applied to weight lifters and bodybuilders and is cited by wary athletes who avoid strength training because they do not want to become inflexible.

This is a myth.

It is simply not true that strength training leads to shortening of tendons and ligaments or loss in their pliability.

The truth is that an athlete either stretches and is flexible or isn’t. Strength training will not dictate flexibility one way or the other. This is certainly true of the program presented here, which, as we just discussed, is not designed to lead to big increases in muscle mass.

MYTH: I will have to go to a gym and use barbells and machines. Those modes of training can certainly be effective, but there is more than one way to skin a cat. You do not need to join a gym and use machines in order to strength  train. With a minimal amount of equipment, you can do everything you need to do almost anywhere you choose to do it.

MYTH: Strength training will take up too much time. When I do presentations on strength training to large groups of runners, I start by asking, how many people had a running injury over the previous year? A forest of hands go up. I then ask, how many injuries involved a layoff of at least a week? Most hands stay up. A month? A lot of hands remain in the air. Three months or more? Some hands are still up.

Then I pose this question: If you could have avoided the injury by spending just 15–20 minutes, 2–3 times a week, doing strength work in your own home, would you have been willing to do it?

For most of us, taking up strength training is a no-brainer when we look at it this way. In the long run, strength training will give you more time to hit the roads, not less, and that is exactly what this book will provide. By following the structured workout plan presented here, you can fit all the strength training you need to do into a minimal amount of time and also avoid the injuries that are responsible for the real disruptions to your workout schedule. 

MYTH: Muscle turns to fat if you stop lifting weights. This is a persistent misconception supported by many examples of former weight lifters who have gotten fat after they stopped working out. But this conclusion mistakes coincidence with causality. Muscle can no more turn into fat than lead can turn into gold. They are different types of tissue. But if you get in the habit of eating more to support the extra calorie burn that strength training provides and then fail to dial back the eating when you stop strength training, those extra calories will be stored as fat, not because you stopped strength training, but because you’re taking in more calories than you are using.

MYTH: Strength training is not for women. Obviously, this myth applies to only half the population, and fortunately it is a myth that is rapidly dying out. It wasn’t that long ago that women were considered physically unable to compete in long distance running, and that strength training was considered “unladylike.”

Today, that view has been largely replaced by acceptance and encouragement of female participation in sport, prompted in large part by the enactment in 1972 of federal legislation barring sex  sexual discrimination in any higher education program that receives federal financial assistance, known colloquially by its chapter heading, Title IX.

Nevertheless, for that minority of people who still believe that sweating and grunting and pushing for athletic excellence is something suited only for men, they need only take a quick glance at the women who are participating on pro sports teams, at women’s Olympic achievements, and at their road racing success to become convinced that there is nothing unfeminine about striving for athletic excellence.

-Example Strength Exercise for Runners-


Muscle Targets: Glutes, lower back, abs (transverse)
Equipment: Medicine ball (advanced)


1. Lie faceup on your exercise mat, with your knees bent, your legs together, and your feet flat on the floor.

2. Raise your hips in the air until you have achieved a straight line from your knees to your upper body.

REP: Lower down to the starting position. This constitutes 1 rep.

TIP: Be sure to keep the raised leg in the same position throughout; only your hips should be rising up.

# REPS: 20-50

COACH’S NOTE: This exercise works the muscles on the back of your body, especially the glutes, while also providing a good stretch for the hip flexor muscles on the front of your body.

Stretch one leg straight out, and hold it just a couple of inches off the floor. Now push off your other foot and raise your hips up in the air. Perform the target number of reps, then repeat on the other side


This is similar to the one-legged form above, except with one leg planted on a medicine ball instead of on the floor, which engages the hamstrings of your planted leg as they prevent the ball from rolling away.

Republished with permission of VeloPress from Quick Strength for Runners by Jeff Horowitz. Download free strength exercises at velopress.com/qsr