TY  - GEN
A1  - Schaefer, Laura
A1  - Carnarius, Friederike
A1  - Dech, Silas
A1  - Bittmann, Frank
T1  - Repeated measurements of Adaptive Force
T2  - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe
N2  - The Adaptive Force (AF) reflects the neuromuscular capacity to adapt to external loads during holding muscle actions and is similar to motions in real life and sports. The maximal isometric AF (AFisomax) was considered to be the most relevant parameter and was assumed to have major importance regarding injury mechanisms and the development of musculoskeletal pain. The aim of this study was to investigate the behavior of different torque parameters over the course of 30 repeated maximal AF trials. In addition, maximal holding vs. maximal pushing isometric muscle actions were compared. A side consideration was the behavior of torques in the course of repeated AF actions when comparing strength and endurance athletes. The elbow flexors of n = 12 males (six strength/six endurance athletes, non-professionals) were measured 30 times (120 s rest) using a pneumatic device. Maximal voluntary isometric contraction (MVIC) was measured pre and post. MVIC, AFisomax, and AFmax (maximal torque of one AF measurement) were evaluated regarding different considerations and statistical tests. AFmax and AFisomax declined in the course of 30 trials [slope regression (mean ± standard deviation): AFmax = −0.323 ± 0.263; AFisomax = −0.45 ± 0.45]. The decline from start to end amounted to −12.8% ± 8.3% (p < 0.001) for AFmax and −25.41% ± 26.40% (p < 0.001) for AFisomax. AF parameters declined more in strength vs. endurance athletes. Thereby, strength athletes showed a rather stable decline for AFmax and a plateau formation for AFisomax after 15 trials. In contrast, endurance athletes reduced their AFmax, especially after the first five trials, and remained on a rather similar level for AFisomax. The maximum of AFisomax of all 30 trials amounted 67.67% ± 13.60% of MVIC (p < 0.001, n = 12), supporting the hypothesis of two types of isometric muscle action (holding vs. pushing). The findings provided the first data on the behavior of torque parameters after repeated isometric–eccentric actions and revealed further insights into neuromuscular control strategies. Additionally, they highlight the importance of investigating AF parameters in athletes based on the different behaviors compared to MVIC. This is assumed to be especially relevant regarding injury mechanisms.
T3  - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 831 
KW  - Adaptive Force
KW  - maximal isometric Adaptive Force
KW  - holding capacity
KW  - neuromuscular control
KW  - strength vs. endurance athletes
KW  - injury mechanisms
KW  - repeated adaptive isometric–eccentric muscle action
KW  - holding (HIMA) and pushing (PIMA) isometric muscle action
Y1  - 2023
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/58803
UR  - https://nbn-resolving.org/urn:nbn:de:kobv:517-opus4-588030
SN  - 1866-8364
IS  - 831
ER  -