4-second repeats. Fitness is fast and scientific
NASA Experiments with Power-Cycle

NASA purchased a Power-Cycle for experiments to discover the types of exercise that best slow the loss of muscle size and strength during 70 days of simulated space flight 1.  They were very surprised to discover that performing 4-second sprints using Power-Cycle once every 7-10  days reduced the loss of muscle size and power by more than one-half of what they normally observe after 70 d of simulated space flight.   To further investigate Power-Cycle, NASA contracted a top research lab to determine if a single Power-Cycle brief workout (6 x 4-sec sprints at maximal intensity) causes rapid improvements in the molecular signals known to stimulate the building of muscle fiber size and power 2.  Remarkably, only 24 (6 x 4-sec) seconds of total exercise using Power-Cycle caused large increases in the cellular signals for muscle growth (i.e.; mRNA of myogenin, MuRF-1, MHC etc.) especially in Fast-Twitch muscle fibers2. Approximately one-half of the fibers in our muscles are Fast-Twitch and they are rarely activated because modern people don’t normally have reason to sprint or perform fast and powerful muscle movements.  These findings demonstrate that although Power-Cycle bouts are only 4-seconds in duration, they are very potent exercise for stimulating muscle growth and offsetting muscle loss from inactivity.  Clearly, astronauts and modern man need to ‘engineer’ powerful movements back into daily life.  Power-Cycle is the safe, time efficient, rewarding and fun method for accomplishing that need.


1) Ploutz-Snyder, L. L., M. Downs, E. Goetchius, B. Crowell, K. L. English, R. Ploutz-Snyder, J. W. Ryder, E. L. Dillon, M. Sheffield-Moore, and J. M. Scott. 2018. ‘Exercise Training Mitigates Multisystem Deconditioning during Bed Rest’, Medicine and Science in Sports and Exercise, 50: 1920-28.

2) Trappe, T. et al.  Board 32- Metabolic and Skeletal Muscle Molecular Responses to a NASA Exercise Paradigm. Integrated Physiology of Exercise- ACSM & APS.  San Diego, CA (9/10/18).