Pumping Iron for the Long Haul

It seems logical that greater strength would improve endurance performance. After all, don’t pro cyclists have bulging quads and swimmers strut around showing off their “V” shape and those door-filling shoulders? Shouldn’t the simple route to better running, cycling, and swimming go directly through the weight room? What could be better than pumping iron all winter, then showing up at the first race of the season not only faster but buff as well?

It isn’t that simple. There are important reasons for endurance athletes to strength train. But while authorities differ, it’s becoming increasingly obvious that toiling in the weight room probably won’t directly improve your performance in your chosen endurance sport unless you’re a novice for whom any physical improvement, no matter what kind, will elicit better times.

What Do the Studies Say?
The relationship between strength and endurance is uncertain, and studies haven’t clarified it. It makes intuitive sense that “you can’t make a strong cyclist or runner out of a weak person.” However, in practice there’s a tremendous gap between the physiological abilities needed to perform a few repetitions with heavy weights compared to the thousands of low-resistance repetitions that characterize endurance activities like cycling or running.

A quick look at several studies shows why this issue is so confusing. In one study, previously untrained men cycled to exhaustion, then did a three-times-weekly resistance program consisting of standard leg exercises (like leg presses, hamstring curls and calf raises) in sets of 10 to 12 repetitions. After eight weeks, cycling performance on the test improved even though VO2max, a key endurance indicator, didn’t budge. However, in a study using experienced riders, a similar weight training regimen caused their 40K time trial performances to slow by nearly two minutes in a one-hour event.

Why the discrepancy? Experts theorize that the sedentary subjects improved their cycling performance with weight training because, due to their lack of fitness, any physical improvement translated into faster riding. But the experienced cyclists got worse because when their regular training routines on the bike were combined with the added stress of resistance training, they became overtrained and too tired to perform well.

Leg Presses and Cycling Performance: A Personal Odyssey
My personal experience confirms these results. As an undersized but enthusiastic football player, I was able to compete in college because I gained nearly 50 pounds through a combination of weight training and conscientious overeating (love those milkshakes!). When I started bike racing, the pounds melted away and I returned to my normal weight. But the experience sold me on the benefits of weights, so during the winter I did exhausting squat and leg press workouts—as many as 50 reps of squats with 200 pounds, sets of 10 to 15 reps with over 700 pounds in the leg press. I couldn’t wait until spring; I had visions of not only blowing away all the other riders on hills but also breaking crankarms and tearing spokes out of my rear hub.

But as I soon found out, all that work had made me pretty good at squats and leg presses but not so good at cycling. I got dropped like a rock in the early races, and it took several months of riding before I came around. The moral: Weight room strength has to be converted to cycling-specific fitness before it’s of much use on the bike.

That’s true for other endurance sports as well. Owen Anderson, PhD, in his respected newsletter Running Research News (http://www.rrnews.com), says it best: “When most runners go to the gym, they focus on the usual, traditional, tried-and-true exercises—bench presses, squats, power cleans—such exercises are great for developing generalized strength but there is one small problem: None of them has anything to do with running.”

The Weak Link Theory
To make sense of this phenomenon, consider what University of Utah exercise physiologist and World Masters Cycling champ Steve Johnson PhD, calls the “weak link theory.” He maintains that there’s always at least one weak link in any person’s power production mechanism. It might be strength, aerobic capacity, lactate tolerance, or endurance. If you lack strength, weight training is necessary. But if you’re a former football player who can leg press 700 pounds, the weak link is probably in the aerobic systems, and it makes sense to spend the majority of training time on the bike rather than in the weight room.

Why Endurance Athletes Should Strength Train—Even if They Won’t Get Faster
So does this mean that most endurance athletes are better off skipping the weights and spending all their time running, cycling, or swimming instead? No. Here’s why:

• Sarcopenia. That ominous word refers to the body’s disturbing tendency to lose muscle mass as we age. According to some authorities, strength stays relatively high until we reach 50 then begins a precipitous decline of as much as 10% a year. If the slide continues unabated, we face a lengthy period of physical decline and inability to perform simple tasks of daily living like getting out of chairs and carrying groceries. As we age, we need to lift to keep the muscle we have.
  
  
• Functional Strength. As we have seen, weight training can improve endurance performance but only if the exercises mimic the demands of the sport. So instead of a diet of squats and bench presses, runners should do running-specific exercises like one-leg squats, hill bounding and lunges. Cyclists would do step-ups and various on-bike drills like sprints and hard jams up short, steep hills-that build strength specific to the pedaling motion. Such an approach is called “functional strength,” and it’s currently a hot idea in training.
  
  
• Injury Prevention. A strong athlete is a more injury-resistant athlete. Take cycling—a rugged upper body is less likely to get hurt in a crash. A runner with strong muscles surrounding the knee is less likely to fall prey to chrondomalacia, (pain under the kneecap when kneeling, running or climbing stairs) and other overuse injuries. Think of it this way: Resistance training keeps the chassis strong so you can work on your motor.