We discussed it here last February and it's made the news often lately: stretching before a workout or game does not prevent injury in the short term or soreness the next day. We saw here last month that the usual pain-killers many of us pop like popcorn fail to prevent injuries, delay healing from them, and can even cause more serious health problems. So how do we help prevent injury and/or soreness during or after hard exercise, whether in the gym, on the playing field, or in the yard?
Warming up and cooling down come to mind, don't they? Let's see what they do to and for us. Are they beneficial? Are they worth the time they take? Can young, fit athletes skip them without consequence? Does that change with age?
What's our motivation for warming up and cooling down? Forget preventing DOMS - the Delayed-Onset Muscle Soreness -- that makes tying our shoes an impossible, excruciating task one to four days after that weekend warrior fiasco. Warming up and cooling down do not prevent DOMS, but because it's so closely related, we'll look at preventing DOMS below.
"If it doesn't prevent subsequent soreness, why bother warming up?", you ask. "Injury prevention, better performance, and cardiac safety", the experts respond. The first time we contract a dormant muscle, it doesn't take us seriously. It reacts much like Garfield the cat might, using less than one percent of its fibers ... just enough to get moving. Only after we keep up the activity, cycling the muscle through many contractions and relaxations, is it persuaded to recruit more fibers, enabling it to absorb more stress and exert more force. It's like a rope made of a bundle of smaller strings; when the whole rope works together, it can actively lift more weight and survive stronger external forces than one cord can manage. You can thus jump higher, lift more, throw further and run faster - and are far less likely to injure or even snap a muscle fiber -- after warming up and recruiting more muscle fibers. Warming up makes the musculoskeletal engine stronger, plain and simple. And doing your thing slow before doing it fast is an effective muscle-specific boost to your warmup.Higher muscle and joint temperatures boost nerve signal transmission, oxygen and fuel metabolism, muscle fiber recruitment, joint mobility and safety, and muscle compliance ("slipperyness"). None of these functions are ready for really hard exertion until they are made fully operational by mild exercise. Even active kids can play harder and safer if they start slowly. By middle age our muscles lose appreciable pliability, so warmups become even more important to muscle integrity and performance.
Now let's escalate the stakes. It's not just soreness or some potential muscle injury at stake. Our heart gets quickly involved, too. When you start a bout of physical exertion, your cardiovascular system has to shift the vast majority of your blood from your belly organs to your skeletal muscles, increasing their muscle blood flow by up to 1,500 percent. This requires a great deal of blood vessel dilation and redistribution pumping effort, and if you demand too much of your skeletal muscles before those are accomplished, your blood pressure skyrockets. That's unhealthy for fit people, downright dangerous for the rest of us. Two of my young, fit, fellow Air Force Officer Training School candidates died from running their daily 1.5 mile immediately after breakfast, because their cardiovascular system could not adapt quickly enough to divert blood from their digestion system to their brain's temperature control mechanism without proper warmup, even in the south Texas August heat.
Specifically, asking too much of muscles - including your heart -- before their blood supply is shifted and ramped up is asking for pain or damage in them. The extra stress in our heart of too much exercise too quickly often produces heart arrythmias. Similarly, joint lubrication fluid needs to be warmed, thinned, and redistributed by mild activity before the joints are asked to work hard, or the injury rate climbs.
Convinced about warm-ups? Here's how they're done. Exercise most of your body until you start to sweat from the exercise, then gradually focus the exercise on the muscles you intend to work hard soon. Longer warm-ups are necessary for older people, less fit people, more strenuous exertion, or colder starts. It's going to take 5-15 minutes, and should produce a little sweat and temperature elevation, not fatigue. End it with full-range-of-motion reaches to dynamically extend your muscles, instead of the static stretches less-informed people still do. Cranking up the car heater on the way to the gym or the game is not effective.
Warming up for a workout, yard work, or an individual sport such as a run through the park can be done simply by beginning slowly and under complete control until we start to sweat - 10-15 minutes - then pouring it on. But that's not appropriate in competition, where we should be playing hard from the opening gun. For competition, pre-game calisthenics are the solution.
On the bright side, once we're in shape, we no longer get sore ... right? Sorry ... wrong. The very mechanism that makes us sore is the one that is required to get stronger. Improving our athletic capability requires muscle damage, and the muscle damage is what causes the soreness. Let's elaborate.
DOMS is not caused by lactic acid, cold muscles, swelling, or tight muscles. It's caused by the same process required to strengthen our muscles: heavy exertion against increasing resistance generates microscopic tears in the muscles, making them sore before they heal and stronger after they heal. Getting stronger/quicker requires that we exercise until our muscles feel heavy and start to hurt, and that leads to DOMS, especially when we're out of shape. To get a little stronger, you must accept a little DOMS. No DOMS, no gain. Thus serious athletes, to get progressively stronger and/or quicker, exercise hard and fast through discomfort to real muscle fatigue, then exercise lightly for a day or two until the soreness disappears and they can again exercise intensely again without real-time soreness. Working too hard too often diminishes their capability.
To help reduce DOMS after opening day of a new sports season, the beginning of an escalated workout program, or a major yard project, try getting those same muscles a little sore ahead of time with similar but lighter exercise. A little deliberate advance soreness helps many people avoid real soreness after the real thing. No, those electric stimulation belts hyped on late-night TV do not warm us up (or strengthen us or burn fat). As with most truly important facets of our lives, there are few effective shortcuts.
Now go play, but cool down properly afterwards. Even prime athletes can pass out if they fail to cool down properly. While exercising, our legs help our hearts pump blood. When our legs stop, our heart must increase its workload instantly and significantly to keep expelling heat and metabolic wastes. When it can't compensate fast enough to maintain our blood pressure and oxygen flow, out and down we go. If we're on grass, it's called fainting. If we're on concrete, it may be called a skull fracture. Slow down over minutes, not seconds, after vigorous exercise, until your heart rate is comfortable (at least below 120) and your breathing and sweating have slowed significantly. And now, while your muscles are deeply warmed up, is a great time for some serious stretching for long-term muscle and joint benefit.
For greater detail on this and other sports health topics, check out http://www.brianmac.demon.co.uk/siteindx.htm. A quick look at some of its extensive topics revealed logical, non-controversial, fairly up-to-date, thorough, flexible tutorials. It expects a lot from us, so people with days shorter than 30 hours may have to tone down his recommendations. Fortunately he explains things well enough that readers can make intelligent choices about how far they want to take their exercise.