Astronauts face broken exercise machines

Exercising on Earth is tough enough, but astronauts on the International Space Station have more than weightlessness to overcome — in the form of inadequate equipment.

Judith Hayes of NASA’s Johnson Space Center said each of the International Space Station’s three exercise machines has had mechanical problems, and it’s rare for all to be completely functional at the same time.

Speaking at the Aerospace Medical Association’s recent meeting in Orlando, Fla., Miss Hayes said each astronaut is given a custom exercise “prescription” by the flight surgeons in Mission Control. Typically, that consists of two hours of intense exercise, six days a week. The three exercise machines are a treadmill, a bicyclelike device and a “weight room.”

The intense exercise is necessary to maintain the health of the astronauts in space and ensure they can safely exit from their spacecraft in an emergency or an off-course landing, officials said. For missions to the moon or Mars, the astronauts will have to maintain their physical strength enough to exit their spacecraft and do useful tasks on the surface.

Other scientists at the meeting presented studies on exercises and medical kits for missions to the moon and Mars. Any exercise equipment, they said, will have to fit inside a 1-cubic-foot box, weigh a maximum of 22 pounds, and make use of far less volume than what’s available on existing spacecraft.

Students from Dartmouth College demonstrated one possibility — stretching elastic nylon straps for various muscle groups.

Another concern for long-term spaceflight is how drugs and food decay over time, especially antibiotics, antihistamines and vitamin D. When space shuttle Discovery launches in July, it will carry four identical packages of food and drug samples up to the space station to be tested for durability.

Also discussed at the medical association’s meeting is what to include in a medical kit. NASA flight surgeon J.D. Polk noted that the price of a defibrillator is just a small portion of the actual cost of placing it on the moon. Testing, transportation and storage costs also must be considered.

Dr. Polk said focus should be put on improving astronauts’ health so it becomes extremely unlikely that a defibrillator will ever be needed.

Astronaut Don Pettit spent six months living on the space station.

“If you do include a defibrillator on a lunar mission, you better include four of them,” Mr. Pettit quipped. “Because if the ascent engine [used to lift off of the moon and returns to Earth] fails to ignite, then the entire crew’s going to have simultaneous heart attacks and they’ll each need one.”