TY  - JOUR
A1  - Richter, Charlotte
A1  - Braunstein, Bjoern
A1  - Staeudle, Benjamin
A1  - Attias, Julia
A1  - Suess, Alexander
A1  - Weber, Tobias
A1  - Mileva, Katya N.
A1  - Rittweger, Joern
A1  - Green, David A.
A1  - Albracht, Kirsten
T1  - Contractile behavior of the gastrocnemius medialis muscle during running in simulated hypogravity
JF  - npj Microgravity
N2  - Vigorous exercise countermeasures in microgravity can largely attenuate muscular degeneration, albeit the extent of applied loading is key for the extent of muscle wasting. Running on the International Space Station is usually performed with maximum loads of 70% body weight (0.7 g). However, it has not been investigated how the reduced musculoskeletal loading affects muscle and series elastic element dynamics, and thereby force and power generation. Therefore, this study examined the effects of running on the vertical treadmill facility, a ground-based analog, at simulated 0.7 g on gastrocnemius medialis contractile behavior. The results reveal that fascicle−series elastic element behavior differs between simulated hypogravity and 1 g running. Whilst shorter peak series elastic element lengths at simulated 0.7 g appear to be the result of lower muscular and gravitational forces acting on it, increased fascicle lengths and decreased velocities could not be anticipated, but may inform the development of optimized running training in hypogravity. However, whether the alterations in contractile behavior precipitate musculoskeletal degeneration warrants further study.
Y1  - 2021
U6  - http://dx.doi.org/10.1038/s41526-021-00155-7
SN  - 2373-8065
N1  - Corresponding author: Charlotte Richter
VL  - 7
IS  - Article number: 32
PB  - Springer Nature
CY  - New York
ER  - 
TY  - JOUR
A1  - Richter, Charlotte
A1  - Braunstein, Björn
A1  - Stäudle, Benjamin
A1  - Attias, Julia
A1  - Süss, Alexander
A1  - Weber, Tobias
A1  - Mileva, Katya N.
A1  - Rittweger, Jörn
A1  - Green, David A.
A1  - Albracht, Kirsten
T1  - Gastrocnemius medialis contractile behavior during running differs between simulated Lunar and Martian gravities
JF  - Scientific reports
N2  - The international partnership of space agencies has agreed to proceed forward to the Moon sustainably. Activities on the Lunar surface (0.16 g) will allow crewmembers to advance the exploration skills needed when expanding human presence to Mars (0.38 g). Whilst data from actual hypogravity activities are limited to the Apollo missions, simulation studies have indicated that ground reaction forces, mechanical work, muscle activation, and joint angles decrease with declining gravity level. However, these alterations in locomotion biomechanics do not necessarily scale to the gravity level, the reduction in gastrocnemius medialis activation even appears to level off around 0.2 g, while muscle activation pattern remains similar. Thus, it is difficult to predict whether gastrocnemius medialis contractile behavior during running on Moon will basically be the same as on Mars. Therefore, this study investigated lower limb joint kinematics and gastrocnemius medialis behavior during running at 1 g, simulated Martian gravity, and simulated Lunar gravity on the vertical treadmill facility. The results indicate that hypogravity-induced alterations in joint kinematics and contractile behavior still persist between simulated running on the Moon and Mars. This contrasts with the concept of a ceiling effect and should be carefully considered when evaluating exercise prescriptions and the transferability of locomotion practiced in Lunar gravity to Martian gravity.
KW  - Bone quality and biomechanics
KW  - Environmental impact
KW  - Skeletal muscle
KW  - Tendons
KW  - Ultrasound
Y1  - 2021
U6  - http://dx.doi.org/10.1038/s41598-021-00527-9
SN  - 2045-2322
N1  - Corresponding author: Charlotte Richter
VL  - 11
IS  - Article number: 22555
PB  - Springer Nature
CY  - London
ER  -