Puffy Head, Bird-Leg Syndrome

KSNNTM thanks the NASA SCI FilesTM for this activity. Visit http://scifiles.larc.nasa.gov and learn more about challenges for manned missions to Mars in The Case of the Great Space Exploration.

When astronauts are in space, they experience the phenomenon known as "Puffy-Head, Bird-Leg" Syndrome. The astronauts feel a sensation of sinus stuffiness and develop puffiness in the face. Measurements taken before, during, and after space flight show that legs do change their shape during space flight. Astronauts with a larger leg circumference show a larger decrease in leg volume than astronauts with smaller legs. This change in shape makes sense because increased muscle requires more fluid and blood flow to feed that muscle. The more blood and fluid there is in one area, the more there is to move. The reported sensations in the head and the measured changes in the legs support the hypothesis that fluids in the body shift upwards during space flight.

Teacher Note: Students who participate in this activity should be wearing pants or shorts.

To simulate the effects of a reduced gravity environment on the human body.

Students should work in pairs or small groups.
• For each group:
• Stopwatch or clock with a second hand
• cm measuring tape

1. Using a measuring tape, measure the circumference of your leg near the top of the thigh. Record this measurement. Label the time and circumstances for this measurement (original measurement).
2. Sit on the floor facing the wall.
3. Put your feet up on the wall with your legs as flat against the wall as possible.
4. As soon as you are settled, stay still and begin timing for three minutes.
5. At the end of three minutes, stand quickly and measure your leg again. Be sure to measure at the same place on your leg each time.
6. Record your measurement. Label the time and circumstances for this measurement (legs in the air measurement).
7. Walk around the room several times or jog in place.
8. Measure your leg again. Record this measurement. Label the time and circumstances for this measurement (jogging in place measurement).

1. What happened to the circumference of your leg after you had your feet up on the wall?
2. Why do you think this change happened?
3. How is this result similar to what the astronauts experience?
4. What happened to your legs after you resumed some physical activity?
5. What can astronauts do to overcome, Puffy-Head, Bird-Leg Syndrome?

1. Learn more about the effects of space on the human body. Look at the "resources" and search for information about what happens to the astronauts in a microgravity environment. Find out what the astronauts do to compensate for these effects.