Adarq.org

All conclusions of studies will be listed in this original post (TABLE OF SUMMARIES) for quick reference.


Post any study regarding MUDR / Rate coding on strength, explosiveness, and performance.



1. Motor-unit discharge rates in maximal voluntary contractions of three human muscles

An argument is presented that suggests that, in response to voluntary effort, the range of discharge rates of each motor-unit pool is limited to those only just sufficient to produce maximum force in each motor unit.

2. Maximal motor unit discharge rates in the quadriceps muscles of older weight lifters.

Results: As expected, knee extension strength in the trained weight lifters (367.0 +/- 72.0 N) was significantly greater than that in the control subjects (299.9 +/- 35.9 N;P < 0.05). Motor unit discharge rates were similar in the two subject groups at the 50% MVC force level (P > 0.05), but maximal (100% MVC) motor unit discharge rate in the weight lifters (23.8 +/- 7.71 pps) was significantly greater than that in the age-matched controls (19.1 +/- 6.29 pps;P < 0.05).

3. Adaptations in maximal motor unit discharge rate to strength training in young and older adults

In response to resistance training, maximal voluntary force increased 25% in young and 33% in older subjects (P < 0.001). Maximal MUDR increased significantly (11% young, 23% older) on day 2 [F(3,36) = 2.58, P < 0.05], but in older subjects returned to baseline levels thereafter.

4. Quadriceps muscle strength, contractile properties, and motor unit firing rates in young and old men

5. Fatigue of submaximal static contractions.

The single unit EMG recordings suggest that, in sustained and repeated submaximal contractions, muscle contractile failure is compensated by recruitment of additional motor units rather than by rate coding of those already active. During intermittent contractions large increases in the surface EMG were associated with only modest increases in firing rates. In sustained contractions when the EMG was held constant the discharge rates declined in parallel with the force. In constant force contractions involving about 35% muscle contractile failure no changes in discharge rates were seen despite substantial increases in EMG.