A significant main effect for time was observed ( P < @ ) , whereby the intervention group increased isometric neck strength in all planes after the @-week intervention ( F preintervention = @ @ N vs F postintervention @ @ N ; E preintervention = @ @ vs E postintervention = @ @ N ; LSF preintervention = @ @ N vs LSF postintervention = @ @ N ; RSF preintervention = @ @ N vs RSF postintervention = @ @ N ) .