This material is for information only and is not an offer or invitation to contract. Plans may be subject to medical underwriting or other restrictions. Rates and benefits vary by location. Health benefits and health insurance plans contain exclusions and limitations. Providers are independent contractors and are not agents of Aetna. Provider participation may change without notice. Aetna does not provide care or guarantee access to health services. Information is believed to be accurate as of the production date; however, it is subject to change.
For years, expert opinion has been mixed on whether long-distance running helps or hurts hearts. In the 1970s, research suggested that marathon running and a heart-healthy diet would completely prevent atherosclerosis (a buildup of harmful plaque in the arteries). But since high-profile runners have died of heart attacks, scientists in the 1980s began to worry that running might actually harm the vital organ. Compounding this fear in recent years were studies suggesting that male endurance athletes exhibited more signs of heart scarring or plaques than their less-active counterparts.
If a car is powered by electricity, however, the energy has to be stored in batteries that have a much lower energy density than gasoline does. To carry 300 miles’ worth of energy, an electric car would need a lot of very heavy batteries. Furthermore, it is difficult to deliver the energy needed to power an electric car in an acceptably short time. Modern battery-powered cars charge at a rate roughly a thousand times slower than the rate of refueling with gasoline, meaning overnight charging is required to store enough energy for a day’s worth of driving. For most Americans in the fast-paced 21st century, that’s an unacceptably long time span.