High intensity training during spaceflight: results from the NASA Sprint Study

• Published in: NPJ microgravity 2020-08, Vol.6 (1), p.21-21, Article 21
• Main Authors: English, Kirk L., Downs, Meghan, Goetchius, Elizabeth, Buxton, Roxanne, Ryder, Jeffrey W., Ploutz-Snyder, Robert, Guilliams, Mark, Scott, Jessica M., Ploutz-Snyder, Lori L.
• Format: Article
• Language: English
• Subjects: 631/443; 692/308/409; Applied Microbiology; Biomedical and Life Sciences; Biotechnology; Bone density; Bone mineral density; Cardiorespiratory fitness; Classical and Continuum Physics; Dual energy X-ray absorptiometry; Exercise; Immunology; Life Sciences; Long bone; Muscle strength; Physical fitness; Space Exploration and Astronautics; Space flight; Space Sciences (including Extraterrestrial Physics
• ISSN: 2373-8065; 2373-8065
• DOI: 10.1038/s41526-020-00111-x

Historically, International Space Station (ISS) exercise countermeasures have not fully protected astronauts’ musculoskeletal and cardiorespiratory fitness. Although these losses have been reduced on more recent missions, decreasing the time required to perform in-flight exercise would permit reallocation of that time to other tasks. To evaluate the effectiveness of a new training prescription, ISS crewmembers performed either the high intensity/lower volume integrated Sprint resistance (3 d wk −1 ) and aerobic (interval and continuous workouts, each 3 d wk −1 in alternating fashion) exercise program ( n  = 9: 8M/1F, 48 ± 7 y, 178 ± 5 cm, 77.7 ± 12.0 kg) or the standard ISS countermeasure consisting of daily resistance and aerobic exercise ( n  = 17: 14M/3F, 46 ± 6 y, 176 ± 6 cm, 80.6 ± 10.5 kg) during long-duration spaceflight. Bone mineral density (dual energy X-ray absorptiometry (DXA)), muscle strength (isokinetic dynamometry), muscle function (cone agility test), and cardiorespiratory fitness (VO 2peak ) were assessed pre- and postflight. Mixed-effects modeling was used to analyze dependent measures with alpha set at P