Exercise safety

ABRAHAM LINCOLN CAPITAL AIRPORT, Illinois -- With warmer weather here many will return to the great outdoors for exercise and recreation. Many enjoy riding their bicycle for either fitness or just fun. With that in mind let's go through some items to make your time in the saddle a little safer. The National Highway Traffic Safety Administration reports that, in 2005, 784 bicycle riders were killed in collisions with cars and trucks, and 45,000 were injured. Of the deaths, 684 were male, and 380 were at night. About 540,000 bicyclists visit emergency rooms with injuries every year. Of those, about 67,000 have head injuries, and 27,000 have injuries serious enough to be hospitalized. Here are Six Ways to Protect Yourself.

Wear a helmet. One in eight of the cyclists with reported injuries had a brain injury, and two-thirds of the deaths in bicycle accidents are from traumatic brain injury. Helmets would prevent an estimated 45-to-88 percent of cyclists' brain injuries.

Be visible. Or, as the BicycleSafe web site says, "Ride as if you were invisible." Wear bright clothing during the day. At night, wear reflective clothing. A bright headlight is recommended for night riding. Most night-time bicyclists ride without lights.

Avoid busy streets and ride on a bike path if possible.

Take the whole lane when you are able to keep up with the flow of traffic. Drivers will see you better and won't try to squeeze by you. Otherwise, stay as far right on the pavement as possible, watching for opening car doors, sewer gratings, soft shoulders, and debris.

Obey your local traffic laws.

Learn your bicycle's capabilities: handling, speed, turning and stopping.

Along with warmer weather comes increased risk for dehydration and heat stroke. During heavy exercise, the human body can generate ten to twenty times the amount of heat that it does at rest. Since only 20 percent of that heat is used to do work, the rest must be dissipated. That extra heat is transferred from the core of the body (mainly muscles) to the skin, where it can be released to the environment. Because heat transfer is accomplished by increasing blood flow to the skin, it is vital to keep up the blood volume, which means keeping up hydration. In addition, evaporation of sweat is the body's major mechanism for heat dissipation while exercising. Sweat is composed mainly of water, with a small amount of sodium. Dehydration therefore clearly robs the body of its ability to cope with heat stress, and increases the risk of heat illness. In fact, a fluid loss of 1 percent of total body weight can increase the body's core temperature.

Heat cramps, heat exhaustion, and heatstroke are conditions of water and often sodium loss. Heat cramps represent the least dangerous of these conditions. They typically occur during or after intense exercise in the heat and usually involve the legs. Sodium is lost in the sweat, and is further diluted in the blood if plain water is used to replace fluid losses. Heat cramps usually resolve with rest, cooling down, and massaging the affected muscles. Prevention involves acclimatization to heat and staying on top of fluid and salt status before exercising. It is most important to note that heat cramps may be a warning sign of a more serious heat illness.

Heatstroke is a medical emergency in which the body's cooling mechanisms are overwhelmed. Dehydration and lack of acclimatization usually contribute. The appearance of a heatstroke patient ranges from moderate confusion to coma and a high body temperature. Victims almost always continue to sweat; many people believe that sweating has stopped in the case of heatstroke, but this is seldom true. Because heatstroke can rapidly progress to collapse of vital organ systems, these patients need immediate treatment in a medical facility.

The best medicine is prevention. To reduce the risk of heat injuries use the following guidelines from the Mayo clinic:

Take it slow. If you're used to exercising indoors or in cooler weather, take it easy at first. As your body adapts to the heat, gradually increase the length and intensity of your workouts. If you have a chronic medical condition or take medication, ask your doctor if you need to take additional precautions.

Drink plenty of fluids. Your body's ability to sweat and cool down depends on adequate rehydration. Drink plenty of water prior to and while you're working out -- even if you don't feel thirsty. If you're planning to exercise intensely or for longer than one hour, consider sports drinks instead. These drinks can replace the sodium, chloride and potassium you lose through sweating. Avoid drinks that contain caffeine or alcohol, which actually promote fluid loss.

Dress appropriately. Lightweight, loose fitting clothing promotes sweat evaporation and cooling by letting more air pass over your body. Avoid dark colors, which can absorb the heat. A light-colored hat can limit your exposure to the sun.

Avoid midday sun. Exercise in the morning or evening -- when it's likely to be cooler outdoors -- rather than the middle of the day. If possible, exercise in the shade or in a pool.

Wear sunscreen. Sunburn decreases your body's ability to cool itself.

Have a backup plan. If you're concerned about the heat or humidity, stay indoors. Work out at the gym, walk laps inside the mall or climb stairs inside an air-conditioned building.

Enjoy the nice weather safely!