Endurance of the latissimus dorsi, elbow flexors, and pectorals was assessed by the number of pull-ups the subject was able to complete. Endurance of the pectoral and shoulder muscles was assessed by the number of push-ups the subject was able to complete in 2 minutes, and abdominal muscle endurance was assessed by the number of sliding crunches the subject was able to complete in 2 minutes.

RESULTS:
This experiment has concluded in ground-based studies sponsored by the National Aeronautics and Space Administration's (NASAs) Human Adaptation and Countermeasures Division. This experiment was conducted during Bed Rest Campaigns 1 and 3, 5, Artificial Gravity (AG), and Head Down Tilt - 30 day (HDT30).

There was no significant change in flexibility when comparing pre- bed rest day 2 to post- bed rest day 1. This may be due to the fact that subjects followed a daily stretching routine during the bed rest. Both genders had reduced endurance after bed rest. Both male and female subjects showed a significant reduction in strength between pre- and post- bed rest scores. The biceps and muscles of the back are used very little during bed rest, which leads to a reduction in muscular endurance. The tests of the leg press show a significant change from the pre- and post. During bed rest the subjects are not permitted to use their lower bodies; this provides the best representation to space flight that the investigators could record with Functional Fitness testing. Subjects lost substantial percentages of lower body strength from pre- bed rest day 2 to post- bed rest day 1. Strength returned to nearly the original pre- bed rest score on the final day of post-testing.