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, Bjoern
A1  - Stäudle, Benjamin
A1  - Attias, Julia
A1  - Suess, Alexander
A1  - Weber, Tobias
A1  - Mileva, Katja N.
A1  - Rittweger, Joern
A1  - Green, David A.
A1  - Albracht, Kirsten
T1  - Gastrocnemius medialis contractile behavior is preserved during 30% body weight supported gait training
JF  - Frontiers in Sports and Active Living
N2  - Rehabilitative body weight supported gait training aims at restoring walking function as a key element in activities of daily living. Studies demonstrated reductions in muscle and joint forces, while kinematic gait patterns appear to be preserved with up to 30% weight support. However, the influence of body weight support on muscle architecture, with respect to fascicle and series elastic element behavior is unknown, despite this having potential clinical implications for gait retraining. Eight males (31.9 ± 4.7 years) walked at 75% of the speed at which they typically transition to running, with 0% and 30% body weight support on a lower-body positive pressure treadmill. Gastrocnemius medialis fascicle lengths and pennation angles were measured via ultrasonography. Additionally, joint kinematics were analyzed to determine gastrocnemius medialis muscle–tendon unit lengths, consisting of the muscle's contractile and series elastic elements. Series elastic element length was assessed using a muscle–tendon unit model. Depending on whether data were normally distributed, a paired t-test or Wilcoxon signed rank test was performed to determine if body weight supported walking had any effects on joint kinematics and fascicle–series elastic element behavior. Walking with 30% body weight support had no statistically significant effect on joint kinematics and peak series elastic element length. Furthermore, at the time when peak series elastic element length was achieved, and on average across the entire stance phase, muscle–tendon unit length, fascicle length, pennation angle, and fascicle velocity were unchanged with respect to body weight support. In accordance with unchanged gait kinematics, preservation of fascicle–series elastic element behavior was observed during walking with 30% body weight support, which suggests transferability of gait patterns to subsequent unsupported walking.
KW  - AlterG
KW  - rehabilitation
KW  - gait
KW  - walking
KW  - ultrasound imaging
KW  - series elastic element behavior
KW  - muscle fascicle behavior
KW  - unloading
Y1  - 2021
U6  - http://dx.doi.org/10.3389/fspor.2020.614559
SN  - 2624-9367
VL  - 2021
IS  - 2
PB  - Frontiers
CY  - Lausanne
ER  - 
TY  - CHAP
A1  - Richter, Charlotte
A1  - Braunstein, Bjoern
A1  - Stäudle, Benjamin
A1  - Attias, Julia
A1  - Suess, Alexander
A1  - Weber, T.
A1  - Rittweger, Joern
A1  - Green, David A.
A1  - Albracht, Kirsten
T1  - In vivo fascicle length of the gastrocnemius muscle during walking in simulated martian gravity using two different body weight support devices
T2  - 23rd Annual Congress of the European College of Sport Science, Dublin, Irland
Y1  - 2018
ER  -