One-Year Mission on ISS Is a Step Towards Interplanetary Missions.

Area of Science:

• Space medicine
• Human physiology in microgravity
• Astronaut health

Background:

• Russian cosmonauts completed long-duration Mir missions (312-438 days) in the 1990s.
• A 340-day joint U.S./Russian mission on the International Space Station (ISS) was completed in 2015 by Scott Kelly and Mikhail Kornienko (KM).

Purpose of the Study:

• To assess the efficacy of countermeasures against microgravity's adverse effects.
• To compare physical exercise intensity and post-flight motor changes between a 1-year ISS mission and shorter missions.

Main Methods:

• Measured in-flight physical exercise intensity in KM and six cosmonauts on shorter ISS flights (173.3 ± 13.8 days).
• Assessed post-flight motor changes in KM and the comparison group using similar microgravity countermeasures.

Main Results:

• Both exercise intensity and motor changes varied similarly despite differing ISS mission durations.
• KM maintained adequate physical performance throughout his 1-year flight.
• KM's post-flight changes were comparable to cosmonauts who completed 6-month ISS missions.

Conclusions:

• The 1-year ISS mission demonstrated the high efficacy of the countermeasures utilized by KM.
• These findings support the feasibility of extended space missions, including interplanetary travel.