Page 149 - 《运动与健康科学》(英文)2024年第2期
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TaggedAPTARAFigure
           TaggedAPTARAEndMotor units’ adaptations to disuse and active recovery                                 271



























































           Fig. 4. Swarm plots representing the MUs DR at (A) recruitment, (B) derecruitment, and (C) during the steady-state phase at the 3 data collection points. From left
           to right, MUs properties are presented for the 3 different submaximal contraction intensities (i.e., 10%, 25%, and 50% MVC). Individual MUs are represented by
           dots and clustered by subject. Summary data are presented as mean § SEM, and the direction of the changes is highlighted by a connection line. Significance
           levels are: * p < 0.05, ** p < 0.01, *** p < 0.001. AR = active recovery; DR = discharge rate; LS = limb suspension; MUs = motor units; MVC = maximal volun-
           tary isometric contraction; pps = pulses per second; SEM = standard error of the mean.TaggedAPTARAEnd


           DDR RT returned to baseline levels at AR21. At AR21at 10%  lateralis muscle predominantly by reducing the DR of lower-
           but not at 25% MVC, DForce RT returned to baseline levels.  but not higher-threshold MUs. Moreover, 21 days of AR
                                                                 (about twice the duration of ULLS) based on resistance exer-
           No changes were identified in the pool of tracked MUs.TaggedAPTARAEnd
                                                                 cise is sufficient to restore neural control and even to suggest
                                                                 the beginning of an exercise-induced overcompensation,
           TaggedAPTARAH14. DiscussionTaggedAPTARAEnd
                                                                 highlighting the remarkable functional plasticity of the neural
             TaggedAPTARAPThe main finding of this study was that a short period of  components.TaggedAPTARAEnd
           unloading of the dominant lower limb (i.e., 10 days of ULLS)  TaggedAPTARAPThe threshold-specific alterations of MUs DR demonstrate
           in young healthy men is sufficient to induce a detectable alter-  a different impact of disuse on the motoneurons innervating
           ation of the neural strategies used to control muscle force  lower- and higher-threshold MUs in the large vastus lateralis
           production (referred to here as neural control 9,10 ) in the vastus  muscle. This finding shows a similarity with the seminal work
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