Occupational-Specific Strength Predicts Astronaut-Related Task Performance in a Weighted Suit

Area of Science:

• Human factors and performance in extreme environments.
• Space exploration and astronaut health.

Background:

• Future space missions necessitate accurate prediction of astronaut task completion time (TTC) for safety and mission success.
• Astronauts will perform critical tasks in planetary spacesuits, often in a deconditioned state.
• Current strength testing may not fully capture the demands of occupationally relevant tasks.

Purpose of the Study:

• To determine if task-specific strength testing enhances TTC prediction in a simulated space environment.
• To compare the predictive power of standard lower body strength tests versus combined standard and occupationally specific strength tests.

Main Methods:

• Eight participants performed standard NASA lower body strength tests and occupationally specific strength tests.
• Participants completed simulated tasks (e.g., hand drilling, wrenching, sample collection) in a 48-kg weighted suit.
• Linear regression models were used to predict total TTC using different strength test combinations.

Main Results:

• Standard lower body strength tests predicted 61% of the variability in total TTC.
• The addition of hand drilling and wrenching strength tests improved TTC prediction accuracy to 99%.
• Total TTC for the test battery ranged from 20.2 to 44.5 minutes.

Conclusions:

• Occupationally specific strength tests, particularly for hand drilling and wrenching, are crucial for accurately predicting astronaut task performance in weighted suits.
• These findings support the integration of task-specific strength assessments into astronaut pre-mission evaluations.
• Further research with higher-fidelity simulations is recommended to validate these predictive models.