Project in Brief
This investigation aim at presenting an exercise solution to maintain or even improve important aspects of physical performance i.e., muscle strength and endurance, in space travelers on long-haul missions. Physiological adaptations to acute exercise will be determined parallel to validation of novel exercise machine designs. Secondly, an extensive laboratory study will assess aerobic capacity, endurance, strength and size, and molecular markers of skeletal muscle hypertrophy and vascular and mitochondrial growth in response to chronic, concurrent flywheel resistance and aerobic exercise.
Healthy men, age 20-30, perform 5 wks either resistance training only, or concurrent, unilateral aerobic AND resistance training using YoYo™ technology. Unilateral knee extensor resistance exercise is carried 2 or 3 x wk-1, with 4 sets of 7 maximal coupled concentric and eccentric actions performed by each leg. One leg also executes ~45 min continuous aerobic knee extensor exercise 3 x wk-1. Aerobic capacity, muscle endurance and strength, and volume of quadriceps femoris muscles, are assessed by means of MRI pre and post training. Similarly, in biopsies obtained from m. vastus lateralis, markers reflecting e.g., mitochondrial and aerobic function, and muscle growth are determined. More specifically changes in activation state of pathways held to be important in regulating muscle size, and mitochondrial biogenesis and angiogenesis are analyzed.
This study will disclose whether concurrent aerobic and resistance training using flywheel technology will induce favorable physiological changes, including skeletal muscle molecular adaptations, similar to those elicited by resistance training only. Equally important, this project will advance exercise hardware and protocols for terrestrial applications and for astronauts on extended missions in Orbit.
Our overarching research focus is to develop and validate different physical exercise interventions to combat skeletal muscle dysfunction induced by e.g., disuse, disease, spaceflight or aging.
Research in the field
- Tesch PA, von Walden F, Gustafsson T, Linnehan RM, Trappe TA. Skeletal muscle proteolysis in response to short-term unloading in humans. J Appl Physiol 105: 902-905. 2008.
- Tesch PA, Berg HE, Bring D, Evans HJ, and Leblanc AD. Effects of 17-day spaceflight on knee extensor muscle function and size. Eur J Appl Physiol 93: 463-468, 2005.
- Alkner BA, and Tesch PA. Knee extensor and plantar flexor muscle size and function following 90 days of bed rest with or without resistance exercise. Eur J Appl Physiol 93: 294-305, 2004.
- Tesch PA, Trieschmann JT, and Ekberg A. Hypertrophy of chronically unloaded muscle subjected to resistance exercise. J Appl Physiol 96: 1451-1458, 2004.