Ah, warmer weather at last! Time to get out there and throw that–ouch!–ball, and swing that–ooh!–golf club, and jog around the–oof!–lake…and then, more than likely, turn on that–aah!–heating pad, fill that–mmm–ice pack, and slip into–whew!–bed.
Yes, ’tis the season for athletic injuries, as those who haven’t done anything except shovel snow for half a year sudden remember that once upon a time they had other forms of recreation–something their bodies have forgotten.
Sports injuries are one of the most common kinds of injuries we inflict on ourselves. It’s not too surprising, either, when you consider the strain sports put on our bodies. A runner’s foot pounds against a hard surface hundreds of times per kilometer, a tennis player’s shoulder swings a racket hundreds of times in a match, and a basketball players knee has to soften the heavy landing after every lay-up. Some activities add other dangers: a fall off a bicycle can be very nasty indeed, and indeed, surveys of emergency room records indicate bicycle riding is the most injury-prone activity. However, even “safe” activities like walking, statistically speaking, will cause an injury once every four years, while runners, on average, injure themselves once every five months.
There are two basic types of sports injuries: acute injuries, such as pulled muscles, sprained joints and broken bones, and overuse injuries, which are caused by overdoing a repetitive activity such as golfing, walking or running. Both types of injuries are so common that just about everyone has suffered them; yet at the same time, most of us suffer them without ever knowing what’s really happened. Herewith, therefore, I present the physiology of some common sports injuries for your elucidation.
The most common complaint by anyone just resuming activity after a winter’s lay-off is sore muscles, properly called delayed-onset muscle soreness (because it starts hours after the exercise that causes it), is probably caused by microscopic injury to muscle tissue.
More serious than just sore muscles is a pulled muscle. This is muscle tissue that has been overstretched, and usually occurs between joints, in areas such as the thigh (i.e., a groin pull). Muscle pulls can occur when muscle tissue is stretched as it attempts to contract, or if it is stretched beyond its normal range. Cells in the muscle are ruptured or even torn apart, which, not surprisingly, hurts. It takes at least 25 days for torn muscle tissue to form scar tissue, even though the pain disappears a lot sooner, which is why, if you’re not careful, it’s easy to “re-pull” that same muscle even after you think you’re long over the injury.
Among the most common pulled muscles are the hamstrings, which originate at the base of the buttocks and extend down the leg to just behind the knee–in other words, the whole back of your thigh. The hamstring’s function is to flex the knee. Since they normally only contract, and are rarely stretched, if you suddenly do something that does stretch them–running very fast, for example–without enough warm-up or stretching exercises, a pull is quite likely.
A cramp is an uncontrolled spasm or contraction of a muscle, which causes severe pain and loss of function. Cramps can be caused by overworking a muscle; they can also be the result of an imbalance of electrolytes–charge-carrying chemicals such as potassium, sodium, calcium, magnesium and chloride that are necessary to the proper contraction of muscle cells. Since you lose electrolytes when you sweat, muscle cramps are more common in very hot weather.
Muscle tissue can also be damaged by a sudden blow, which happens quite often in football. This muscle bruise is sometimes called a “charleyhorse”–and interesting word whose origin I intended to look up but didn’t!
Many sports injuries occur in the joints, which isn’t surprising, since every joint in the body is a complex junction of bones, muscles, connective tissues such as ligaments and tendons, fascia (a fibrous material that covers muscle) and fluids. The tendons are very susceptible to injury because they’re smaller than most muscles and located at the high-stress joints. If they’re damaged, they can become inflamed, causing swelling and soreness in the joint. (Inflammation is actually part of the healing process: blood vessels in the tissue surrounding the injury dilate and release a variety of substances that summon white blood cells to remove dead tissue and other debris. This produces the heat, swelling and redness; the pain and stiffness, meanwhile, serve the beneficial function of keeping you from moving the joint and aggravating the injury.) Tendons can also rupture, literally separating from the bone or muscle they’re attached to. This usually occurs during a violent contraction, such as weightlifting, or after constant repetition–baseball pitchers, for example, are susceptible.
There are a whole series of tendon-related injuries with their own catchy names, such as tennis elbow, jumper’s knee and policeman’s heel. All of them are related. They probably begin to form when a few fibers of tendon are stretched or torn, which causes a slight inflammation as the healing process begins. However, if the action that caused the injury–say, hitting a tennis ball–is repeated over and over again, before the injury has a chance to heal completely, the joint is in a constant state of inflammation, never quite healing, and always hurting.
The term “shin splints” is medically outdated–doctors prefer terms like “medial tibial stress syndrome”–and for good reason: it encompassed a number of different types of injuries occurring in the lower leg, including tendonitis and stress fractures–actual cracks in bones.
Any joint can be sprained, but the most common joint to be sprained is the ankle. They’re due to stretched or ruptured ligaments–tough, fibrous bands of tissue which extend from bone to bone, holding the joint together. Put them under too much stress, and presto! A sprain. Inflammation and pain follow, just as they do for any other injury.
Sports injuries are always going to occur, but many of them could be prevented if people would take it a little easier when they first begin exercising after a long lay-off, or increase the level of exercise they’re doing. Careful stretching of joints and muscles before beginning exercise could also save people a lot of pain later on.
But when spring is in the air and everyone thinks they’re 18 again, that’s probably too much to ask.