Densely populated wireless local area networks (WLANs) can encounter issues with processing multiple user (MU) uplink (UL) transmissions sent from many stations (STAs) simultaneously. The access points (AP) or master stations in these densely populated WLANs must manage the UL MU transmissions. To accomplish the management of the UL MU transmissions, a system for dynamically setting UL MU parameters is provided that can modify or set one or more parameters that govern how each STA is to transmit data to the AP. The parameters may be sent to one or more of the STAs in one or more transmissions and may direct how the STAs are to transmit data for at least some portion of time.