Less is More?

When Warming Up for Exercise, Less May Be More

Few aspects of sports are as wrapped in myth as the warm-up. Most of us dutifully warm up in some way before we work out or compete, but according to a new study, “little is known about how an athlete should warm up.” In fact, as that study and other recent research make clear, the more scientists study warm-ups, the less they seem to understand about the practice.

The new study found, for instance, that some athletes warm up so thoroughly that they are too tired to perform well afterward. In the study, which waspublished last month in The Journal of Applied Physiology, researchers at the University of Calgary in Alberta asked track cyclists to complete, on alternate days, their usual warm-up or a shorter, easier version. Cyclists, especially those who sprint around a circular velodrome, are well known (even notorious) for the length and intricacy of their warm-ups.Few aspects of sports are as wrapped in myth as the warm-up. Most of us dutifully warm up in some way before we work out or compete, but according to a new study, “little is known about how an athlete should warm up.” In fact, as that study and other recent research make clear, the more scientists study warm-ups, the less they seem to understand about the practice.

“We suspected that that warm-up was harder than it should be,” said Brian R. MacIntosh, a professor of kinesiology at the University of Calgary and an author of the study, along with Elias K. Tomaras, a graduate student.In this case, the volunteers, highly trained male racers, first followed their standard warm-up routine, beginning with 20 minutes of riding. The intensity of the pedaling increased until it reached about 95 percent of each rider’s maximal heart rate. That session was followed immediately by four hard intervals, or timed sprints, during which the rider would pedal as hard as he could for eight minutes.

A year earlier, Dr. MacIntosh had studied sprint skaters’ warm-ups as part of the national skating team’s preparation for the 2010 Winter Olympics. The skaters “were warming up for two hours for a 35-second race,” Dr. MacIntosh said. Afterward, he found, the skaters’ leg muscles contracted with less force than they’d generated before the warm-up. In warming up their muscles, they’d fatigued them.

The cyclists, as it turned out, were similarly tiring their muscles during their standard warm-up. When the researchers stimulated the riders’ leg muscles electrically, they found that the muscles contracted more forcefully before the riders’ usual warm-up than after it.

After a more leisurely 15-minute warm-up, though, with the highest intensity reaching only about 65 percent of each rider’s maximal heart rate and including only one interval, the riders’ legs were significantly less fatigued, the researchers found. Their muscles contracted with more force during electrical stimulation than after the standard warm-up, and the riders performed significantly better during a 30-second all-out pedaling effort on a specialized stationary bicycle.

“This research provides an argument against the traditional ‘more is better’ warm-up concept that is adopted by many competitive athletes,” Dr. MacIntosh and his colleague wrote in their study, which they helpfully titled “Less Is More.”

Unfortunately, the study did not answer some fundamental questions about warming up, beginning with whether most of us need to be engaging in the practice at all.

“We don’t know the answer to that question,” Dr. MacIntosh said. A warm-up is thought to allow tissues literally to become heated, to reach a temperature at which they are, presumably, more flexible and malleable and ready for the demands of further exercise. But it hasn’t been proved that warm muscles perform better than colder ones or that they are less prone to injury, Dr. MacIntosh said.

According to the largest review and analysis to date of the research on warm-ups, which was published last year in The Journal of Strength and Conditioning Research, a warm-up was “shown to improve performance” to a limited extent in most of the sports studied, which included running, swimming, cycling, golfing, basketball, softball and bowling. But as the review’s lead author, Andrea Fradkin, an associate professor at Bloomsburg University in Pennsylvania, told me, most of the studies were small-scale and short-term, and their methods were inconsistent.

In some studies, people stretched to warm up, she said. In others, she said, “they did jumping jacks or passed a medicine ball around and then raced bicycles.” None of the studies persuasively showed that any one approach to warming up was best, or even that a warm-up necessarily would make you significantly better at your sport or prevent injury.

The science about how to warm up “is not well advanced,” Dr. Fradkin said. “We haven’t answered the big questions yet,” she said, about whether to warm up or why to warm up, “let alone the smaller, specific ones” about how.

Which may leave many of us wondering if those 15 or 20 minutes (or, rarely, two hours) that most of us have been devoting to preparing our bodies for a full workout may have been wasted.

“I wish I could say, one way or the other,” Dr. MacIntosh said. “But we don’t know. My guess is that, if you’ve been following a warm-up routine for a while and you haven’t gotten injured and you perform well when you race, then that warm-up is working for you. Keep it up.”

On the other hand, if your legs feel heavy and slow after your warm-up, you might be overdoing it. Experiment with shortening and reducing the intensity of your warm-up, Dr. MacIntosh suggests. “And if you find something that works, let us know,” he urged. You will notably have advanced the state of knowledge in this particular field of exercise science.