Warm up before exercise and how to avoid soreness after exercise
How should I warm up before exercise?
After reading the last post about the negative effects of static stretching before your workout, you might be thinking, “Great! Now, instead of wasting my time warming up, I can get down to business right away.”
Nothing could be further from the truth. In fact, the stretching studies reinforce the point that subtle differences in how you prepare your body can make a big difference in your performance during a workout or competition.
The general goals of a warm-up are “to increase muscle and tendon suppleness, to stimulate blood flow to the periphery, to increase body temperature, and to enhance free, coordinated movement,” according to a group of U.S. Army researchers who studied the problem in 2006. A gentle jog accomplishes some of these goals—raising body temperature, for instance—but it doesn’t do much to prepare the specific muscles that will help you lift a weight, throw a ball, or cut sideways across the court. Instead, you need to perform a series of exercises that move your muscles through the full range of motion that you plan to use, at first gently and then with increasing vigor. This is a dynamic warm-up, focused on movement rather than the static poses of a traditional stretching routine.
Over the past decade, a series of studies has tested the principles of dynamic warm-up. The U.S. Army study had recruits perform one of two 10-minute warm-up routines, one dynamic and one static. Those who performed the dynamic warm-up produced significantly better performances in three tests of agility and power (a shuttle run, an underhand medicine-ball throw, and a five-step jump), compared with static stretchers and those who did no warm-up at all. Other dynamic warm-up studies have found improvements in vertical jump, bicycle sprint, oxygen uptake, and even coordination.
Most of these studies focus on the acute effects of warming up—after all, we’re most interested in how our warm-up affects the workout that follows. But University of Wyoming researchers posed an interesting question in a 2008 study: What are the long-term benefits of repeated dynamic warm-ups? Using the same warm-up routine as the Army study, the researchers monitored a group of collegiate wrestlers for four weeks. At the end of the trial, the dynamic warm-up group had improved on a whole battery of tests of strength, endurance, agility, and anaerobic capacity (for example, broad jump, sit-ups, push-ups, 600-meter run, and so on). A matched group that did static stretching instead of the dynamic warm-up saw no improvement in any of the tests.
The precise details of a dynamic warm-up depend on the demands of the activity you’re preparing for, but Louisiana State University researcher Jason Winchester suggests breaking it down into three basic stages:
1. A low-intensity, rhythmic activity to elevate heart rate and body temperature; for example, at least five minutes of jogging, swimming, or biking.
2. A few minutes of dynamic drills that put your muscles through the range of motion you’ll be using; for example, squats, arm windmills, and skipping. Do 10 repetitions of each one.
3. Finish with some skill-specific motions to prepare for your activity. If you’re lifting weights, lift a few reps with a light load; before a tennis match, hit some easy ground strokes; or run a few relaxed sprints before a hard run.
These basic principles can be adapted for just about any sport or physical activity, focusing on motions that prepare your muscles for the challenges ahead. The more vigorous or explosive the activity, the more thoroughly you should warm up.
Will stretching after exercise help me avoid next-day soreness?
In 1986, researchers at the Free University of Amsterdam asked a group of volunteers to perform a set of strenuous exercises with one leg, while resting the other leg. Over the next three days, the scientists poked, prodded, and measured the legs in an effort to understand why certain exercises cause us to feel sore—not immediately after the exercise, but usually beginning the next day and often peaking two days later. One of the tests involved using electrodes to record the electrical activity in each leg, in order to look for differences between the sore leg and the rested leg. None were found. This was a very significant result, because it helped rule out a dominant theory of “delayed-onset muscle soreness,” or DOMS, that was first proposed in the 1960s. The theory argued that, after heavy exercise, damaged muscles went into spasm, blocking blood flow and causing the observed pain. The Dutch experiment put an end to that idea.
As often happens, the advice spawned by a discredited theory lived on long after the theory. Researchers in the 1960s had proposed that the best way to deal with these hypothetical spasms was to stretch the affected muscle, allowing normal blood flow to resume. Exercisers obediently began stretching after exercise in the hope of avoiding next-day soreness. And to this day, they still do.
Given that the spasm theory has been abandoned, it shouldn’t come as much of a surprise that studies of post-exercise stretching have found little or no effect on soreness. The most recent lab experiment, published in 2009, put a group of 20 Australian rowers through a series of grueling stair-climbing workouts (the muscle contractions required to go down stairs or down hills are particularly effective in causing soreness).
Some of the rowers did a 15-minute static stretching routine after the workout, while others simply rested for 15 minutes; a week later, they switched. Over the three days following each workout, the researchers found no differences at all between the two groups in muscle strength, perceived soreness, or blood levels of a marker of muscle damage called creatine kinase.
Other researchers have tried similar experiments outside the lab. For instance, an Australian football team allocated different players to different recovery protocols, including either rest or a 15-minute post-game stretching session, each week over the course of 12 weeks. On a whole host of measures, including soreness, vertical jump, peak power on a stationary bike, and flexibility, there was no difference between the groups.
The trend in these studies is consistent. An independent review of 25 studies on the topic, published in 2008 by the Cochrane Collaboration, found “very consistent” evidence that stretching has “minimal or no effect on the muscle soreness experienced between half a day and three days after [exercise].”
Of course, you may have other reasons to stretch after a workout. If you’re hoping to increase flexibility, that’s the best time to stretch, since your muscles are still warm and the performance-dampening effects of stretching don’t matter once the workout’s over. But, sadly, it won’t stop you from getting sore.
Where is my “core,” and do I need to strengthen it?
These days, it’s all about the core. Whether it’s yoga, Pilates, exercise balls, or dozens of other fitness programs and gadgets, there’s no greater selling point than a promise to improve your core stability.
And researchers now agree—for the most part—that weak core muscles can indeed be a key culprit in everything from lower back pain to sports injuries, says Reed Ferber, a kinesiology professor who directs the University of Calgary’s Running Injury Clinic. “What people don’t agree on,” he adds, “is what the core is.”
In particular, there’s a tendency to focus too much on the abdominal and lower back muscles. But pelvic and hip muscles also play a crucial role in stabilizing the body during activity and are now generally considered part of the “core.” Ferber cites the example of a 40-year-old woman who came to him as a patient with knee pain. “She had a fantastic six-pack, and did Pilates or yoga six days a week,” he says.
But the woman was unable to balance long enough to do a simple one-legged squat—bending at the knee while standing on one leg—because her hip muscles weren’t strong enough to provide balance. This instability was the root cause of her knee injury.
The same pattern was borne out by a seven-month study of patients at Ferber’s clinic, 92 percent of whom turned out to have abnormally weak hip muscles (and 89 percent of whom improved with four to six weeks of hip strengthening). Similarly, a University of Delaware study of basketball and track athletes found that the best predictor of who would develop leg injuries during the season was weakness in one of the hip muscles.
Even for the abdominal muscles, not all exercises are created equal. A study presented at the American College of Sports Medicine’s 2008 annual meeting found that traditional crunches, which involve curling the torso up, mainly activate superficial “six-pack” muscles rather than the “deep abdominal” muscles that are more crucial for stability. The study, by Auburn University researcher Michele Olson, used EMG electrodes to compare muscle activation produced by various core exercises.
Pilates exercises in which the torso stays unflexed, like the “Hundred” (lying on your back and lifting your legs at a 45-degree angle, with your arms at your side) and the “Double Leg Stretch” (similar to the “Hundred” but with your arms also raised at 45 degrees behind your head), were more effective than crunches at strengthening the deep abs instead of superficial muscles.
For elite athletes, designing a core program often begins with a detailed assessment of their strengths and weaknesses, in order to target the weakest areas. But that remains more of an art than a science, Ferber says, so most people would benefit from a fairly general core program—one that includes an activity like Pilates, but also incorporates some more functional exercises that mimic the range of motion used in whatever activity they participate in.
His top suggestion, based on the people he sees at his clinic, is hip exercises, which are relevant for sports ranging from soccer to cycling. And working on the hips offers an important reminder, he adds: “The bottom line is a six-pack does not equal core stability.”