Journal: Cold Spring Harbor Perspectives in Medicine
Article Title: Performance Fatigability: Mechanisms and Task Specificity
doi: 10.1101/cshperspect.a029728
Figure Lengend Snippet: Task dependency of performance fatigability. (A) Power-task duration relation for cycling in young men and women. Shown is the hyperbolic relation for cycling between power (relative to maximum power achieved during a 3-sec test at 80 rpm) and time to failure (trial duration) for multiple cycling tests performed at various power outputs. Over several days of testing, active young men (n = 7) and women (n = 7) performed trials to obtain the peak 3-sec power output (100%) followed by 11 to 14 constant-load tests to elicit failure between 3 and 300 sec. The time constant for the power-duration relationships was 0.0207/sec (R2 = 0.96) so that the greater the relative power the shorter the time to failure. The time constant and shape of the hyperbolic relation did not differ between the sexes. (Figure and data adapted with permission from Sundberg et al. 2017.) (B) Force and position task. Time to failure (mean ± SEM) of sustained isometric submaximal contractions performed with the ankle dorsiflexor muscles for a force task and two positions tasks that differed in load compliance and foot support. Data are extracted from two studies performed on a total of 23 young (18–30 yr) men (n = 12) and women (n = 11) (Hunter et al. 2008b; Yoon et al. 2009a). The subjects were seated with knee at 90 deg of flexion, the ankle in neutral position (0 deg dorsiflexion) and with a load supported at the forefoot equivalent to 20% of maximal voluntary contraction (MVC). The load compliance and support provided to the foot varied between the three tasks: There was no support provided under the foot for the “position unsupported” task, a position task with foot support (position supported) that allowed one degree of freedom of movement at the ankle in the sagittal plane, and a force task (force) in which the forefoot was rigidly attached to a force transducer.
Article Snippet: These differences in fatigability with a cognitive challenge and the interaction with the sex of the individual were not observed in the ankle dorsiflexor muscles ( Vanden Noven et al. 2014 ), reinforcing that the sex difference in fatigability can differ across muscle groups.
Techniques: Muscles
